JP7349807B2 - ophthalmology equipment - Google Patents

Description

Embodiments according to the present invention relate to an ophthalmological apparatus.

The ophthalmological apparatus includes an ophthalmological photographing apparatus for obtaining an image of the eye to be examined, an ophthalmological measuring apparatus for measuring the characteristics of the eye to be examined, and an ophthalmological treatment apparatus for treating the eye to be examined.

Examples of ophthalmological imaging devices include optical coherence tomography that obtains tomographic images using optical coherence tomography (OCT), fundus cameras that take photographs of the fundus, and fundus images that are obtained by laser scanning using a confocal optical system. There are scanning laser ophthalmoscopes (SLOs), slit lamp microscopes, surgical microscopes, etc.

Examples of ophthalmological measurement devices include ocular refraction testing devices (refractometers, keratometers) that measure the refractive characteristics of the eye being examined, tonometers, specular microscopes that measure corneal characteristics (corneal thickness, cell distribution, etc.), There are wavefront analyzers that use a Hartmann-Shack sensor to obtain aberration information about the subject's eye, and perimeter meters and microperimeters that measure visual field conditions.

Examples of ophthalmic treatment devices include laser treatment devices that project laser light onto treatment target areas such as diseased areas, surgical devices for specific purposes (cataract surgery, corneal refractive surgery, etc.), and surgical microscopes. .

In an ophthalmological apparatus, from the viewpoint of the precision and accuracy of an examination, positioning (alignment, tracking) between the apparatus optical system and the eye to be examined not only before the start of the examination but also during the examination is extremely important.

For example, Patent Document 1 discloses a method of projecting a light beam onto the cornea and detecting the reflected image (Purkinje image) to perform alignment.

For example, Patent Document 2 discloses that by determining the amount of movement of the fundus from periodically acquired fundus observation images and controlling an optical scanner according to the determined amount of movement, measurement light is always irradiated onto the same area of the fundus. A method is disclosed for correcting the scanning position so that the scanning position is corrected.

For example, Patent Document 3 discloses a method in which the three-dimensional position of the eye to be examined is specified from two or more captured images obtained by photographing the anterior segment of the eye from different directions, and alignment is performed based on this three-dimensional position. has been done.

Japanese Patent Application Publication No. 8-275921 Japanese Patent Application Publication No. 2013-153793 Japanese Patent Application Publication No. 2013-248376

However, conventional methods require an illumination system for observing the retina (fundus of the eye). As a result, the configuration of the optical system becomes complicated, leading to an increase in the size and cost of the optical system. In particular, when the optical paths of a plurality of optical systems are optically coupled, it becomes difficult to separate the wavelengths of the light used in each optical system, which complicates the optical design and makes it difficult to add optical systems. Addition of such an optical system requires an optical element for combining or separating light, resulting in a decrease in the amount of light required for measurement in each optical system, resulting in a decrease in measurement accuracy.

Furthermore, the processing for determining the amount of movement of the fundus as disclosed in Patent Document 2 includes pattern matching processing, which increases the processing load.

The present invention has been made in view of the above circumstances, and its purpose is to provide a new technique for realizing alignment between the fundus of the eye to be examined and the optical system of the device with a simple configuration and processing. It's about doing.

A first aspect of some embodiments includes an optical system that includes an optical scanner and irradiates a subject's eye with light deflected by the optical scanner, an acquisition unit that acquires an anterior segment image of the subject's eye, and the acquisition unit that acquires an anterior segment image of the subject's eye. A corneal incident position where the light enters the cornea of the eye to be examined is identified by analyzing the anterior ocular segment image acquired by the unit, and the light incident on the cornea incidence position is incident on the retina of the eye to be examined. The ophthalmologic apparatus includes an analysis section that specifies a retinal incidence position, and a control section that controls the optical scanner based on a displacement of the retinal incidence position with respect to a reference position on the retina.

A second aspect of some embodiments includes, in the first aspect, an alignment optical system that projects an alignment light beam onto the subject's eye, and the analysis unit is configured to form an anterior segment image based on the alignment light beam. The corneal incident position is specified based on the image obtained.

A third aspect of some embodiments includes, in the second aspect, a moving mechanism that relatively moves the eye to be examined and the optical system, and the control unit adjusts the alignment light beam in the anterior segment image. After controlling the moving mechanism based on the image formed based on the image, the optical scanner is controlled based on the displacement.

In a fourth aspect of some embodiments, in the third aspect, the acquisition unit includes two or more imaging units that image the anterior segment from different directions substantially simultaneously, and the control unit The moving mechanism is controlled based on the position of the above-mentioned photographing unit and the position of the image obtained by analyzing two or more photographed images acquired by the two or more photographing units.

In a fifth aspect of some embodiments, in any one of the first to fourth aspects, the analysis unit may perform an optical analysis of the eye to be examined or a predetermined model eye with respect to the light incident on the cornea incident position. The retinal incident position is specified by performing ray tracing processing using eyeball parameters representing characteristics.

In a sixth aspect of some embodiments, in any one of the first to fifth aspects, the control unit adjusts the amount of change in the angle of incidence of the light at the corneal incident position to the retina. Control information is specified by repeating ray tracing processing so that the amount of change in displacement of the retina incident position with respect to a reference position is within a predetermined threshold, and the optical scanner is controlled based on the control information.

In a seventh aspect of some embodiments, in any of the first to fifth aspects, the control unit performs the control using table information or a function corresponding to the optical characteristics of the eye to be examined or a predetermined model eye. The amount of change in the angle of incidence of the light at the corneal incident position is specified, control information is specified based on the specified amount of change, and the optical scanner is controlled based on the control information.

In an eighth aspect of some embodiments, in the fifth aspect or the seventh aspect, the optical characteristics include corneal shape information of the eye to be examined.

In a ninth aspect of some embodiments, in the eighth aspect, the optical system includes a corneal shape measuring optical system that projects a measurement pattern onto the eye to be examined and detects the returned light, and the corneal shape measuring optical system The apparatus includes a corneal shape calculation unit that calculates the corneal shape information of the eye to be examined based on the detection result of the returned light obtained by the system.

In a tenth aspect of some embodiments, in any of the fifth aspect and the seventh to ninth aspects, the optical property includes a refractive power value of the eye to be examined.

In an eleventh aspect of some embodiments, in the tenth aspect, the optical system includes a refractive power measuring optical system that projects light onto the subject's eye and detects the returned light, and the refractive power measuring optical system The apparatus includes a refractive power value calculation unit that calculates a refractive power value of the eye to be examined based on the detection result of the returned light obtained by.

In a twelfth aspect of some embodiments, in any of the fifth aspect, seventh aspect to eleventh aspect, the optical property includes an intraocular distance of the eye to be examined.

In a thirteenth aspect of some embodiments, in the twelfth aspect, the optical system splits the light from the light source into a reference light and a measurement light, and directs the measurement light deflected by the optical scanner to the eye to be examined. an OCT optical system that projects interference light between the return light from the eye to be examined and the reference light, and detects interference light between the return light from the eye to be examined and the reference light, and based on the detection result of the interference light obtained by the OCT optical system, It includes an intraocular distance calculation unit that calculates an intraocular distance.

In a fourteenth aspect of some embodiments, in the thirteenth aspect, the analysis unit specifies the reference position based on a detection result of the interference light obtained by the OCT optical system.

In a fifteenth aspect of some embodiments, in any of the first to twelfth aspects, the optical system splits the light from the light source into a reference light and a measurement light, and the optical system splits the light from the light source into a reference light and a measurement light, and the light is deflected by the optical scanner. The analysis unit includes an OCT optical system that projects the measurement light onto the eye to be examined and detects interference light between the return light from the eye to be examined and the reference light, and the analysis unit is configured to detect the interference light obtained by the OCT optical system. The reference position is specified based on the light detection result.

Note that it is possible to arbitrarily combine the configurations according to the plurality of aspects described above.

According to the present invention, it is possible to provide a new technique for realizing alignment between, for example, the fundus of the eye to be examined and the optical system of the apparatus through simple processing and processing.

It is a schematic diagram showing an example of composition of an optical system of an ophthalmologic device concerning an embodiment. It is a schematic diagram showing an example of composition of an optical system of an ophthalmologic device concerning an embodiment. It is a schematic diagram showing an example of composition of an optical system of an ophthalmologic device concerning an embodiment. 1 is a schematic diagram showing an example of the configuration of a processing system of an ophthalmologic apparatus according to an embodiment. 1 is a schematic diagram showing an example of the configuration of a processing system of an ophthalmologic apparatus according to an embodiment. 1 is a schematic diagram showing an example of the configuration of a processing system of an ophthalmologic apparatus according to an embodiment. 1 is a schematic diagram showing an example of the configuration of a processing system of an ophthalmologic apparatus according to an embodiment. It is a schematic diagram for explaining processing performed by an ophthalmologic apparatus according to an embodiment. It is a schematic diagram for explaining processing performed by an ophthalmologic apparatus according to an embodiment. It is a schematic diagram showing an example of operation of an ophthalmological device concerning an embodiment. It is a schematic diagram showing an example of operation of an ophthalmological device concerning an embodiment. It is a schematic diagram showing an example of operation of an ophthalmological device concerning an embodiment. It is a schematic diagram for explaining processing performed by an ophthalmologic apparatus according to an embodiment. It is a schematic diagram showing an example of operation of an ophthalmological device concerning an embodiment. It is a schematic diagram showing an example of operation of an ophthalmological device concerning an embodiment. It is a schematic diagram for explaining processing performed by an ophthalmologic apparatus according to an embodiment. It is a schematic diagram showing an example of operation of an ophthalmological device concerning an embodiment.

An example of an embodiment of an ophthalmologic apparatus according to the present invention will be described in detail with reference to the drawings. Note that the contents of the documents cited in this specification and any known technology can be incorporated into the following embodiments.

The ophthalmological apparatus according to the embodiment includes an acquisition unit that acquires an anterior segment image of an eye to be examined, and an optical system that includes an optical scanner and irradiates the eye to be examined (e.g., fundus, retina) with light deflected by the optical scanner. Equipped with The optical system according to some embodiments is configured to irradiate a subject's eye with light polarized by an optical scanner and detect the returned light. Examples of the optical system according to the embodiment include a refractive power measurement optical system, a corneal shape measurement optical system, an OCT optical system, an SLO optical system, a laser irradiation optical system, and the like.

The ophthalmological device identifies (estimates) the retinal incidence position where light from the optical system enters the retina (fundus) from the anterior segment image of the eye to be examined, and uses an optical scanner based on the displacement of the retinal incidence position with respect to the reference position on the retina. control. In some embodiments, a corneal incident position on the cornea where light from the optical system is incident is specified from an anterior segment image of the eye to be examined, and a retinal incident position is specified based on the specified corneal incident position. The reference position on the retina may be specified from a detection result (for example, a tomographic image) obtained by another optical system, or may be specified by the user using an operation unit. This makes it possible to control the optical scanner around a desired position on the retina without observing the retina, making it possible to align the optical system with respect to that position with high precision. . Such control can be used for alignment and tracking between the eye to be examined and the optical system.

Hereinafter, a case will be described in which the ophthalmologic apparatus according to the embodiment mainly performs tracking using the above-described method.

The ophthalmological apparatus according to the embodiment can perform measurement and imaging using OCT. The ophthalmological apparatus according to some embodiments is capable of performing at least one of corneal topography measurement (keratometry) and refractive power measurement (REF measurement) in addition to OCT measurement and the like.

Hereinafter, in the embodiment, a case where a swept source type OCT method is used in measurements using OCT will be explained in detail. It is also possible to apply the configuration according to the embodiment.

The ophthalmological apparatus according to some embodiments further includes a subjective test optical system for performing a subjective test and an objective measurement system for performing other objective measurements.

A subjective test is a measurement technique that uses responses from a subject to obtain information. Subjective tests include subjective refraction measurements such as distance tests, near tests, contrast tests, and glare tests, and visual field tests.

Objective measurement is a measurement method that acquires information regarding the subject's eye mainly using physical methods without referring to responses from the subject. The objective measurement includes measurement for acquiring characteristics of the eye to be examined and photographing for acquiring an image of the eye to be examined. Other objective measurements include intraocular pressure measurement and fundus photography.

Hereinafter, the conjugate position of the fundus is a position that is approximately optically conjugate with the fundus of the subject's eye after alignment has been completed, and means a position that is optically conjugate with the fundus of the subject's eye or its vicinity. Similarly, the pupil conjugate position is a position that is approximately optically conjugate with the pupil of the eye to be examined after alignment has been completed, and means a position that is optically conjugate with the pupil of the eye to be examined or its vicinity. .

<Optical system configuration>
FIG. 1 shows a configuration example of an optical system of an ophthalmologic apparatus according to an embodiment. The ophthalmological apparatus 1000 according to the embodiment includes an optical system for observing the eye E, an optical system for testing the eye E, and a dichroic mirror that separates the optical paths of these optical systems into wavelengths. An anterior segment observation (imaging) system 5 is provided as an optical system for observing the eye E to be examined. As an optical system for testing the eye E, an OCT optical system, a reflex measuring optical system (refractive power measuring optical system), etc. are provided.

The ophthalmologic apparatus 1000 includes an alignment light projection system 2 , a keratometry system 3 , a fixation projection system 4 , an anterior segment observation system 5 , a reflex measurement projection system 6 , a reflex measurement light receiving system 7 , and an OCT optical system 8 . In the following, for example, the anterior segment observation system 5 mainly uses light of 940 nm to 1000 nm, the reflex measurement optical system (the reflex measurement projection system 6, the reflex measurement light receiving system 7) uses light of 830 nm to 880 nm, and the fixation It is assumed that the projection system 4 uses light of 400 nm to 700 nm, and the OCT optical system 8 uses light of 1000 nm to 1100 nm.

(Anterior segment observation system 5)
The anterior segment observation system 5 takes a video of the anterior segment of the eye E to be examined. In the optical system passing through the anterior segment observation system 5, the imaging surface of the imaging element 59 is arranged at the pupil conjugate position. The anterior segment illumination light source 50 irradiates the anterior segment of the eye E with illumination light (for example, infrared light). The light reflected by the anterior segment of the eye E to be examined passes through the objective lens 51, the dichroic mirror 52, the hole formed in the diaphragm (telecentric diaphragm) 53, and the half mirror 23. , relay lenses 55 and 56, and dichroic mirror 76. The dichroic mirror 52 combines (separates) the optical path of the reflex measurement optical system and the optical path of the anterior segment observation system 5. The dichroic mirror 52 is arranged such that an optical path combining surface for combining these optical paths is inclined with respect to the optical axis of the objective lens 51. The light transmitted through the dichroic mirror 76 is imaged by the imaging lens 58 on the imaging surface of the imaging element 59 (area sensor). The image sensor 59 captures images and outputs signals at a predetermined rate. The output (video signal) of the image sensor 59 is input to the processing section 9, which will be described later. The processing section 9 displays an anterior eye segment image E' based on this video signal on a display screen 10a of a display section 10, which will be described later. The anterior segment image E' is, for example, an infrared moving image. The anterior segment image E' may be acquired using an anterior segment camera 300, which will be described later.

(Alignment light projection system 2)
The alignment light projection system 2 aligns the anterior segment observation system 5 in the optical axis direction (anterior-posterior direction, Z direction) and in the direction perpendicular to the optical axis (left-right direction (X direction), up-down direction (Y direction)). The subject's eye E is irradiated with light (infrared light). The alignment light projection system 2 includes an alignment light source 21 and a collimator lens 22 provided in an optical path branched from the optical path of the anterior segment observation system 5 by a half mirror 23 . The light output from the alignment light source 21 passes through the collimator lens 22, is reflected by the half mirror 23, and is projected onto the eye E through the anterior segment observation system 5. Light reflected by the cornea Cr of the eye E to be examined is guided to the imaging device 59 through the anterior segment observation system 5.

An image (bright spot image) Br based on this reflected light is included in the anterior segment image E'. The processing section 9 causes the anterior segment image E' including the bright spot image Br and the alignment mark AL to be displayed on the display screen of the display section. When manually performing the XY alignment, the user can move the optical system so as to guide the bright spot image Br within the alignment mark AL. When manually performing Z alignment, the user can operate the optical system to move while referring to the anterior segment image E' displayed on the display screen of the display unit. When performing automatic alignment, the processing unit 9 satisfies a predetermined alignment completion condition based on the position of a predetermined part (for example, pupil center position) of the eye E to be examined and the position of the bright spot image Br, as described later. This controls the mechanism that moves the optical system.

(Kerato measurement system 3)
The keratometry system 3 projects a ring-shaped light beam (infrared light) onto the cornea Cr of the eye E to be examined. The keratoplate 31 is arranged between the objective lens 51 and the eye E to be examined. A kerato ring light source 32 is provided on the back side of the kerato plate 31 (on the objective lens 51 side). By illuminating the kerato plate 31 with light from the kerato ring light source 32, a ring-shaped obtained light beam (arc-shaped or circumferential measurement pattern) is projected onto the cornea Cr of the eye E to be examined. The reflected light (keratling image) from the cornea Cr of the eye E to be examined is detected by the image sensor 59 together with the anterior segment image E'. The processing unit 9 calculates a corneal shape parameter representing the shape of the cornea Cr by performing a known calculation based on this keratoring image.

(Reflex measurement projection system 6, reflex measurement receiving system 7)
The reflex measurement optical system includes a reflex measurement projection system 6 and a reflex measurement light receiving system 7 used for eye refractive power measurement. The reflex measurement projection system 6 projects a light beam (for example, a ring-shaped light beam) (infrared light) for eye refractive power measurement onto the fundus Ef. The reflex measurement light receiving system 7 receives the returned light from the eye E of this luminous flux. The reflex measurement projection system 6 is provided in an optical path branched by a perforated prism 65 provided in the optical path of the reflex measurement light receiving system 7. The hole formed in the apertured prism 65 is arranged at the pupil conjugate position. In the optical system that passes through the reflex measurement light receiving system 7, the imaging surface of the image sensor 59 is arranged at a conjugate position of the fundus.

In some embodiments, the reflex measurement light source 61 is an SLD (Superluminescent Diode) light source that is a high-intensity light source. The reflex measurement light source 61 is movable in the optical axis direction. The reflex measurement light source 61 is placed at a fundus conjugate position. The light output from the reflex measurement light source 61 passes through the relay lens 62 and enters the conical surface of the conical prism 63. The light incident on the conical surface is deflected and exits from the bottom surface of the conical prism 63. The light emitted from the bottom surface of the conical prism 63 passes through a light-transmitting portion formed in a ring shape in the ring diaphragm 64 . The light (ring-shaped luminous flux) that has passed through the transparent part of the ring diaphragm 64 is reflected by the reflective surface formed around the hole of the apertured prism 65, passes through the rotary prism 66, and is reflected by the dichroic mirror 67. Ru. The light reflected by the dichroic mirror 67 is reflected by the dichroic mirror 52, passes through the objective lens 51, and is projected onto the eye E to be examined. The rotary prism 66 is used to average the light intensity distribution of the ring-shaped light beam to the blood vessels and diseased areas of the fundus Ef and to reduce speckle noise caused by the light source.

The return light of the ring-shaped light beam projected onto the fundus Ef passes through the objective lens 51 and is reflected by the dichroic mirror 52 and the dichroic mirror 67. The return light reflected by the dichroic mirror 67 passes through the rotary prism 66, passes through the hole of the apertured prism 65, passes through the relay lens 71, is reflected by the reflection mirror 72, and is then passed through the relay lens 73 and the focusing lens. Pass through 74. The focusing lens 74 is movable along the optical axis of the reflex measurement light receiving system 7. The light that has passed through the focusing lens 74 is reflected by a reflecting mirror 75, then reflected by a dichroic mirror 76, and is imaged by the imaging lens 58 on the imaging surface of the imaging element 59. The processing unit 9 calculates the eye refractive power (eye refractive power value) of the eye E by performing a known calculation based on the output from the image sensor 59. For example, eye refractive power includes spherical power, astigmatic power and astigmatic axis angle, or equivalent spherical power.

(Fixation projection system 4)
An OCT optical system 8, which will be described later, is provided in an optical path that is wavelength-separated from the optical path of the reflex measuring optical system by the dichroic mirror 67. A fixation projection system 4 is provided in an optical path branched from the optical path of the OCT optical system 8 by a dichroic mirror 83 .

The fixation projection system 4 presents a fixation target to the eye E to be examined. A fixation unit 40 is arranged in the optical path of the fixation projection system 4 . The fixation unit 40 is movable along the optical path of the fixation projection system 4 under control from a processing section 9, which will be described later. Fixation unit 40 includes a liquid crystal panel 41.

The liquid crystal panel 41 under the control of the processing unit 9 displays a pattern representing the fixation target. By changing the display position of the pattern on the screen of the liquid crystal panel 41, the fixation position of the eye E to be examined can be changed. The fixation position of the eye E to be examined may be a position for acquiring an image centered on the macular area of the fundus Ef, a position for acquiring an image centered on the optic disc, or a position for acquiring an image centered on the optic disc, or a position between the macula and the optic disc. There are positions for acquiring images centered on the center of the fundus between the two. It is possible to arbitrarily change the display position of the pattern representing the fixation target.

The light from the liquid crystal panel 41 passes through the relay lens 42 , the dichroic mirror 83 , the relay lens 82 , the reflection mirror 81 , the dichroic mirror 67 , and the dichroic mirror 52 . . The light reflected by the dichroic mirror 52 passes through the objective lens 51 and is projected onto the fundus Ef. In some embodiments, each of the liquid crystal panel 41 and the relay lens 42 is movable independently in the optical axis direction.

In addition, instead of the liquid crystal panel 41, a transmission-type reflex measurement chart with optotypes printed on a film or the like, an illumination light source for illuminating the optotype chart, and a point light source for OCT measurement are used. may be provided.

FIG. 2 shows another example of the configuration of the fixation projection system 4 according to the embodiment. In FIG. 2, parts similar to those in FIG. 1 are designated by the same reference numerals, and description thereof will be omitted as appropriate.

In place of the liquid crystal panel 41, the fixation unit 40 provided in the fixation projection system 4 according to this example is provided with an illumination light source 45a, an optotype chart 46a, and a fixation light source 47a. A fixation light source 47a, an optotype chart 46a, and a relay lens 42 are arranged in this order from the illumination light source 45a toward the dichroic mirror 83. The optotype chart 46a is a transmissive optotype chart placed between the illumination light source 45a and the eye E to be examined, and represents a landscape chart. In some embodiments, the optotype chart 46a is a transparent film with a landscape chart printed on it. In some embodiments, fixation light source 47a is a point light source with a predetermined emission size.

When performing a reflex measurement to be described later, the illumination light source 45a is turned on, and the landscape chart is projected onto the eye E by illuminating the optotype chart 46a with light from the illumination light source 45a. When performing OCT measurement, which will be described later, the fixation light source 47a is turned on, and a bright spot (dot target) (second fixation target) having a narrower visual angle than the landscape chart is projected onto the eye E to be examined. In some embodiments, the fixation light source 47a is turned off when performing reflex measurement, and the illumination light source 45a is turned off when performing OCT measurement. As a result, a landscape chart is presented to the eye E when performing reflex measurement, and a bright spot is presented to the eye E when performing OCT measurement.

In some embodiments, the fixation light source 47a is controlled to blink when performing OCT measurement. In some embodiments, a plurality of fixation light sources 47a are provided, and by selectively turning on the plurality of fixation light sources 47a, the projection position of the bright spot is changed or moved.

The ophthalmologic apparatus 1000 shown in FIG. 1 is provided with two or more anterior segment cameras 300 that photograph the anterior segment of the eye E to be examined from different directions. In this embodiment, two anterior eye cameras are provided on the surface of the ophthalmological apparatus 1000 facing the subject, but the number of anterior eye cameras according to the embodiment is an arbitrary number of 2 or more. . As shown in FIG. 1, each of the two anterior segment cameras is connected to the optical axis of the objective lens 51 (the optical path (optical axis) of the anterior segment observation system 5, the optical path (optical axis) of the OCT optical system 8). It is located in a remote location. Hereinafter, the two cameras may be collectively represented by the reference numeral 300.

In this embodiment, the anterior segment camera 300 is provided separately from the anterior segment observation system 5, but similar anterior segment observation can be performed using at least the anterior segment observation system 5. In some embodiments, one of the two or more anterior segment cameras includes the anterior segment observation system 5 (imaging device 59). The ophthalmologic apparatus 1000 according to the embodiment may be configured to be capable of photographing the anterior segment of the eye from two or more different directions.

In some embodiments, at least one anterior segment illumination source 50 (such as an infrared light source) may be provided near each of the two or more anterior segment cameras. For example, an anterior eye illumination light source provided near the top of one of the anterior eye cameras 300 and an anterior eye illumination light source provided near the bottom of the other, and an anterior eye illumination light source provided near the top of the other anterior eye camera 300. An eye illumination light source and an anterior eye illumination light source provided near the bottom are provided.

The two or more anterior segment cameras can image the anterior segment from two or more different directions substantially simultaneously. "Substantially simultaneously" indicates, for example, that when photographing by two or more anterior segment cameras, a lag in photographing timing is allowed to the extent that eye movement can be ignored. Thereby, images when the eye E to be examined is in substantially the same position (orientation) can be acquired by two or more anterior segment cameras.

Moreover, the imaging by two or more anterior segment cameras may be video imaging or still image imaging. In the case of video shooting, by controlling the shooting start timing to match, controlling the frame rate and the shooting timing of each frame, it is possible to achieve substantially simultaneous anterior segment imaging as described above. . On the other hand, in the case of still image shooting, this can be achieved by controlling the shooting timing to match.

(OCT optical system 8)
The OCT optical system 8 shown in FIG. 1 is an optical system for performing OCT measurement. For example, based on the reflex measurement results performed before OCT measurement, the position of the focusing lens 87 is adjusted so that the end face of the optical fiber f1 is conjugate to the imaging site (fundus Ef or anterior segment) and the optical system. be done. Alternatively, for example, the position of the focusing lens 87 is adjusted so that the intensity of the interference signal obtained by OCT measurement is maximized.

The OCT optical system 8 is provided in an optical path that is wavelength-separated from the optical path of the reflex measurement optical system by a dichroic mirror 67. The optical path of the fixation projection system 4 described above is coupled to the optical path of the OCT optical system 8 by a dichroic mirror 83. Thereby, the respective optical axes of the OCT optical system 8 and the fixation projection system 4 can be coaxially coupled.

OCT optical system 8 includes an OCT unit 100. As shown in FIG. 2, in the OCT unit 100, the OCT light source 101 is a wavelength swept type (wavelength scanning type) light source that can sweep (scan) the wavelength of emitted light, similar to a general swept source type OCT device. It consists of: The wavelength swept light source includes a laser light source including a resonator. The OCT light source 101 temporally changes the output wavelength in a near-infrared wavelength band that is invisible to the human eye.

As illustrated in FIG. 3, the OCT unit 100 is provided with an optical system for performing swept source OCT. This optical system includes an interference optical system. This interference optical system has the function of splitting the light from the wavelength variable light source (wavelength swept type light source) into the measurement light and the reference light, and the return light of the measurement light from the eye E and the reference light via the reference optical path. It has a function of superimposing the two to generate interference light, and a function of detecting this interference light. The detection result (detection signal, interference signal) of the interference light obtained by the interference optical system is a signal indicating the spectrum of the interference light, and is sent to the processing section 9.

The OCT light source 101 includes, for example, a near-infrared variable wavelength laser that changes the wavelength of emitted light (wavelength range of 1000 nm to 1100 nm) at high speed. Light L0 output from the OCT light source 101 is guided to a polarization controller 103 by an optical fiber 102, and its polarization state is adjusted. The light L0 whose polarization state has been adjusted is guided to a fiber coupler 105 by an optical fiber 104 and is split into a measurement light LS and a reference light LR.

The reference light LR is guided to a collimator 111 by an optical fiber 110, converted into a parallel light beam, and guided to a corner cube 114 via an optical path length correction member 112 and a dispersion compensation member 113. The optical path length correction member 112 acts to match the optical path length of the reference light LR and the optical path length of the measurement light LS. The dispersion compensation member 113 acts to match the dispersion characteristics between the reference light LR and the measurement light LS. The corner cube 114 is movable in the direction of incidence of the reference light LR, thereby changing the optical path length of the reference light LR.

The reference light LR that has passed through the corner cube 114 passes through the dispersion compensating member 113 and the optical path length correcting member 112, is converted from a parallel light beam into a convergent light beam by the collimator 116, and enters the optical fiber 117. The reference light LR incident on the optical fiber 117 is guided to a polarization controller 118 to have its polarization state adjusted, guided to an attenuator 120 by an optical fiber 119 to have its light amount adjusted, and guided to a fiber coupler 122 by an optical fiber 121.

On the other hand, the measurement light LS generated by the fiber coupler 105 is guided by the optical fiber f1 and converted into a parallel light beam by the collimator lens unit 89, and passes through the optical scanner 88, the focusing lens 87, the relay lens 85, and the reflecting mirror 84. The light is then reflected by the dichroic mirror 83.

The optical scanner 88 deflects the measurement light LS one-dimensionally or two-dimensionally. The optical scanner 88 includes, for example, a first galvano mirror and a second galvano mirror. The first galvano mirror deflects the measurement light LS so as to scan the imaging region (fundus Ef or anterior segment) in a horizontal direction perpendicular to the optical axis of the OCT optical system 8. The second galvano mirror deflects the measurement light LS that has been deflected by the first galvano mirror so as to scan the imaging region in a vertical direction perpendicular to the optical axis of the OCT optical system 8. Examples of scanning modes of the measurement light LS by the optical scanner 88 include horizontal scanning, vertical scanning, cross scanning, radial scanning, circular scanning, concentric scanning, and spiral scanning.

The measurement light LS reflected by the dichroic mirror 83 passes through the relay lens 82, is reflected by the reflection mirror 81, passes through the dichroic mirror 67, is reflected by the dichroic mirror 52, is refracted by the objective lens 51, and enters the subject's eye E. incident on . The measurement light LS is scattered and reflected at various depth positions of the eye E to be examined. The return light of the measurement light LS from the eye E to be examined travels in the opposite direction along the same path as the outgoing path, is guided to the fiber coupler 105, and reaches the fiber coupler 122 via the optical fiber 128.

The fiber coupler 122 combines (interferes with) the measurement light LS incident through the optical fiber 128 and the reference light LR incident through the optical fiber 121 to generate interference light. The fiber coupler 122 generates a pair of interference lights LC by branching the interference lights at a predetermined branching ratio (for example, 1:1). A pair of interference lights LC are guided to a detector 125 through optical fibers 123 and 124, respectively.

Detector 125 is, for example, a balanced photodiode. The balanced photodiode includes a pair of photodetectors that respectively detect a pair of interference lights LC, and outputs a difference between a pair of detection results obtained by these photodetectors. The detector 125 sends this output (detection signal) to a DAQ (Data Acquisition System) 130.

A clock KC is supplied to the DAQ 130 from the OCT light source 101. The clock KC is generated in the OCT light source 101 in synchronization with the output timing of each wavelength swept within a predetermined wavelength range by the variable wavelength light source. For example, the OCT light source 101 optically delays one of the two branched lights obtained by branching the light L0 of each output wavelength, and then outputs the clock KC based on the result of detecting these combined lights. generate. The DAQ 130 samples the detection signal input from the detector 125 based on the clock KC. The DAQ 130 sends the sampling result of the detection signal from the detector 125 to the arithmetic processing section 220 of the processing section 9 . The arithmetic processing unit 220 forms a reflection intensity profile for each A-line, for example, by applying Fourier transform or the like to the spectral distribution based on the sampling data for each series of wavelength scans (for each A-line). Furthermore, the arithmetic processing unit 220 forms image data by converting the reflection intensity profile of each A line into an image.

In this example, a corner cube 114 is provided for changing the length of the optical path (reference optical path, reference arm) of the reference beam LR, but by using optical members other than these, the measurement optical path length and the reference optical path length can be changed. It is also possible to change the difference between

The processing unit 9 calculates the eye refractive power from the measurement results obtained using the reflex measuring optical system, and determines whether the fundus Ef, the reflex measuring light source 61, and the image sensor 59 are conjugate based on the calculated eye refractive power. The reflex measuring light source 61 and the focusing lens 74 are each moved in the optical axis direction to a position where In some embodiments, the processing unit 9 moves the focusing lens 87 of the OCT optical system 8 in the optical axis direction in conjunction with the movement of the focusing lens 74. In some embodiments, the processing unit 9 moves the liquid crystal panel 41 (fixation unit 40) in the optical axis direction in conjunction with the movement of the reflex measurement light source 61 and the focusing lens 74.

<Processing system configuration>
The configuration of the processing system of the ophthalmologic apparatus 1000 will be described. Examples of the functional configuration of the processing system of the ophthalmologic apparatus 1000 are shown in FIGS. 4 to 7. FIG. 4 represents an example of a functional block diagram of a processing system of the ophthalmologic apparatus 1000. FIG. 5 represents an example of a functional block diagram of the data processing unit 225. FIG. 6 represents an example of a functional block diagram of the alignment processing section 350 of FIG. 5. As shown in FIG. FIG. 7 shows an example of a functional block diagram of the tracking processing section 360 in FIG. 5.

The processing section 9 controls each section of the ophthalmological apparatus 1000. Further, the processing unit 9 is capable of executing various calculation processes. Processing unit 9 includes a processor. The functions of a processor include, for example, a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), an ASIC (Application Specific Integrated Circuit), and a programmable logic device (for example, an SP LD (Simple Programmable Logic Device), CPLD (Complex Programmable Logic Device) , FPGA (Field Programmable Gate Array), and other circuits. The processing unit 9 realizes the functions according to the embodiment by, for example, reading and executing a program stored in a storage circuit or a storage device.

The processing unit 9 is an example of the "ophthalmology information processing device" according to the embodiment. The program for realizing the functions of the processing unit 9 is an example of the "ophthalmology information processing program" according to the embodiment.

The processing section 9 includes a control section 210 and an arithmetic processing section 220. Further, the ophthalmologic apparatus 1000 includes a moving mechanism 200, a display section 270, an operation section 280, and a communication section 290.

The moving mechanism 200 includes optical systems ( This is a mechanism for moving the head section in which the optical system (device optical system) is housed in the front, back, left and right directions. For example, the moving mechanism 200 is provided with an actuator that generates a driving force for moving the head section, and a transmission mechanism that transmits this driving force. The actuator is composed of, for example, a pulse motor. The transmission mechanism is configured by, for example, a combination of gears or a rack and pinion. The control unit 210 (main control unit 211) controls the moving mechanism 200 by sending control signals to the actuators.

Control over the moving mechanism 200 is used for alignment and tracking. Tracking refers to moving the optical system of the apparatus in accordance with the eyeball movement of the eye E to be examined. When tracking is performed, alignment and focus adjustment are performed in advance. Tracking is a function that maintains a suitable positional relationship that is aligned and in focus by causing the position of the device optical system to follow the movement of the eyeballs.

(Control unit 210)
Control section 210 includes a processor and controls each section of ophthalmological apparatus 1000. The control section 210 includes a main control section 211 , a storage section 212 , and an optical system position acquisition section 213 . The functions of the optical system position acquisition section 213 may be realized by the main control section 211. A computer program for controlling the ophthalmologic apparatus 1000 is stored in the storage unit 212 in advance. Computer programs include light source control programs, detector control programs, optical scanner control programs, optical system control programs, alignment control programs, tracking control programs, arithmetic processing programs, user interface programs, etc. It will be done. The control unit 210 executes control processing by operating the main control unit 211 according to such a computer program.

The main control section 211 performs various controls of the ophthalmological apparatus as a measurement control section.

Control of the alignment light projection system 2 includes control of the alignment light source 21 and the like. Control of the alignment light source 21 includes turning on and off the light source, adjusting the amount of light, adjusting the aperture, and the like. Thereby, the alignment light source 21 is switched between lighting and non-lighting, and the amount of light is changed.

Control of the kerato measurement system 3 includes control of the kerato ring light source 32 and the like. Control of the keratoring light source 32 includes turning on and off the light source, adjusting the amount of light, adjusting the aperture, and the like. Thereby, the keratoring light source 32 is switched between lighting and non-lighting, and the amount of light is changed. The main control unit 211 causes the arithmetic processing unit 220 to perform a known calculation on the keratoring image detected by the image sensor 59. Thereby, the corneal shape parameters of the eye E to be examined are determined.

Control of the fixation projection system 4 includes control of the liquid crystal panel 41 and movement control of the fixation unit 40. Control of the liquid crystal panel 41 includes turning on/off the display of the fixation target and switching the display position of the fixation target.

For example, the fixation projection system 4 is provided with a moving mechanism that moves the liquid crystal panel 41 (or the fixation unit 40) in the optical axis direction. Similar to the moving mechanism 200, this moving mechanism is provided with an actuator that generates a driving force for moving the moving mechanism, and a transmission mechanism that transmits this driving force. The main control unit 211 controls the movement mechanism by sending control signals to the actuator, and moves at least the liquid crystal panel 41 in the optical axis direction. Thereby, the position of the liquid crystal panel 41 is adjusted so that the liquid crystal panel 41 and the fundus Ef are optically conjugate.

When the fixation projection system 4 is configured as shown in FIG. 2, the fixation projection system 4 is controlled by the above-mentioned movement control of the fixation unit 40, control of the illumination light source 45a, and control of the fixation light source 47a. There are controls, etc. Control of the illumination light source 45a includes turning on and off the light source, adjusting the amount of light, and the like. Control of the fixation light source 47a includes turning on and off the light source, adjusting the amount of light, and the like.

Control of the anterior eye segment observation system 5 includes control of the anterior eye segment illumination light source 50, control of the image sensor 59, and the like. Control of the anterior ocular segment illumination light source 50 includes turning on and off the light source, adjusting the amount of light, adjusting the aperture, and the like. Thereby, the anterior ocular segment illumination light source 50 is switched between lighting and non-lighting, and the amount of light is changed. Control of the image sensor 59 includes exposure adjustment, gain adjustment, detection rate adjustment, etc. of the image sensor 59. The main control unit 211 captures the signal detected by the image sensor 59 and causes the arithmetic processing unit 220 to execute processing such as forming an image based on the captured signal.

The controls for the anterior eye camera 300 include synchronized control of the shooting start timing of two or more anterior eye cameras and the shooting timing of each frame, and exposure adjustment, gain adjustment, and frame rate adjustment of each anterior eye camera. . Thereby, the anterior segment of the eye E to be examined is photographed substantially simultaneously.

Control of the reflex measurement projection system 6 includes control of the reflex measurement light source 61, control of the rotary prism 66, etc. Control of the reflex measuring light source 61 includes turning on and off the light source, adjusting the amount of light, adjusting the aperture, and the like. Thereby, the reflex measurement light source 61 is switched between lighting and non-lighting, and the light amount is changed. For example, the reflex measurement projection system 6 includes a moving mechanism that moves the reflex measurement light source 61 in the optical axis direction. Similar to the moving mechanism 200, this moving mechanism is provided with an actuator that generates a driving force for moving the moving mechanism, and a transmission mechanism that transmits this driving force. The main control unit 211 controls the movement mechanism by sending a control signal to the actuator, and moves the reflex measurement light source 61 in the optical axis direction. Control of the rotary prism 66 includes rotation control of the rotary prism 66. For example, a rotation mechanism for rotating the rotary prism 66 is provided, and the main control unit 211 rotates the rotary prism 66 by controlling this rotation mechanism.

Control of the reflex measurement light receiving system 7 includes control of the focusing lens 74 and the like. Control of the focusing lens 74 includes control of movement of the focusing lens 74 in the optical axis direction. For example, the reflex measurement light receiving system 7 includes a moving mechanism that moves the focusing lens 74 in the optical axis direction. Similar to the moving mechanism 200, this moving mechanism is provided with an actuator that generates a driving force for moving the moving mechanism, and a transmission mechanism that transmits this driving force. The main control unit 211 controls the movement mechanism by sending a control signal to the actuator, and moves the focusing lens 74 in the optical axis direction. The main control unit 211 controls the reflex measurement light source 61 and the focusing lens 74 to provide light, for example, in accordance with the refractive power of the eye E, so that the reflex measurement light source 61, the fundus Ef, and the image sensor 59 are optically conjugate. It is possible to move it in the axial direction.

Control of the OCT optical system 8 includes control of the OCT light source 101, control of the optical scanner 88, control of the focusing lens 87, control of the corner cube 114, control of the detector 125, control of the DAQ 130, etc. Control of the OCT light source 101 includes turning on and off the light source, adjusting the amount of light, adjusting the aperture, and the like. Control of the optical scanner 88 includes control of the scanning position, scanning range, and scanning speed by the first galvano mirror, and control of the scanning position, scanning range, and scanning speed by the second galvano mirror.

The control of the focusing lens 87 includes controlling the movement of the focusing lens 87 in the optical axis direction, controlling the movement of the focusing lens 87 to a focus reference position corresponding to the imaging region, and controlling the movement range (focusing) corresponding to the imaging region. control of movement within the focal range). For example, the OCT optical system 8 includes a moving mechanism that moves the focusing lens 87 in the optical axis direction. Similar to the moving mechanism 200, this moving mechanism is provided with an actuator that generates a driving force for moving the moving mechanism, and a transmission mechanism that transmits this driving force. The main control unit 211 controls the moving mechanism by sending a control signal to the actuator, and moves the focusing lens 87 in the optical axis direction. In some embodiments, the ophthalmic device 1000 is provided with a holding member that holds the focusing lenses 74 and 87 and a drive unit that drives the holding member. The main control section 211 controls the movement of the focusing lenses 74 and 87 by controlling the driving section. For example, the main control unit 211 may move the focusing lens 87 in conjunction with the movement of the focusing lens 74, and then move only the focusing lens 87 based on the intensity of the interference signal.

Control of the corner cube 114 includes movement control of the corner cube 114 along the optical path. For example, the OCT optical system 8 includes a moving mechanism that moves the corner cube 114 in a direction along the optical path. Similar to the moving mechanism 200, this moving mechanism is provided with an actuator that generates a driving force for moving the moving mechanism, and a transmission mechanism that transmits this driving force. The main control unit 211 controls the movement mechanism by sending a control signal to the actuator, and moves the corner cube 114 in the direction along the optical path. Control of the detector 125 includes exposure adjustment, gain adjustment, detection rate adjustment, detection signal data transfer control, etc. of the detection element. The main control unit 211 samples the signal detected by the detector 125 using the DAQ 130, and causes the arithmetic processing unit 220 (image forming unit 224) to execute processing such as forming an image based on the sampled signal.

The main control unit 211 can execute a plurality of preliminary operations before performing OCT measurement. Preliminary operations include focus adjustment and polarization adjustment. For example, focus adjustment is performed based on interference sensitivity of OCT measurement. For example, as described above, focus adjustment can be performed by finding the position of the focusing lens 87 where the interference intensity is maximum and moving the focusing lens 87 to that position. In the polarization adjustment, the polarization state of the reference light LR is adjusted to optimize the interference efficiency between the measurement light LS and the reference light LR.

The main control unit 211 also functions as a display control unit, including a measured value of the eye refractive power calculated by the eye refractive power calculating unit 221, a parameter representing the corneal shape calculated by the corneal shape calculating unit 222, and an intraocular parameter described below. , information corresponding to the tomographic image formed by the image forming section 224 and the processing results of the data processing section 225, which will be described later, is displayed on the display section 270.

Furthermore, the main control unit 211 performs processing for writing data into the storage unit 212 and processing for reading data from the storage unit 212.

(Storage unit 212)
The storage unit 212 stores various data. Examples of data stored in the storage unit 212 include measurement results of objective measurement, measurement results of OCT measurement, image data of tomographic images, image data of anterior segment images, eye information to be examined, aberration information described below, and There is model eye data (standard value data), etc. The eye information to be examined includes information regarding the eye to be examined, such as left eye/right eye identification information.

The aberration information includes, corresponding to each anterior segment camera 300, a parameter that quantifies the distortion aberration that occurs in the photographed image due to the influence of the optical system. Parameters related to distortion that an optical system imparts to a captured image include principal point distance, principal point position (vertical direction, horizontal direction), lens distortion (radial direction, tangential direction), and the like. For example, the aberration information is configured as information (for example, table information) that associates identification information of each anterior segment camera 300 with a corresponding correction coefficient.

Furthermore, the storage unit 212 stores intraocular parameters 212A representing optical characteristics of the eyeball. The intraocular parameters 212A according to some embodiments include parameters of an eyeball model such as a known model eye. Known model eyes include the Gullstrand model eye and the Helmholtz model eye. Such parameters include size parameters, shape parameters and optical parameters. The size parameter represents the size of a portion or the entire eye. The shape parameter represents the shape of the eye region. Optical parameters describe the optical function of a region of the eye.

Examples of parameters include axial length data, anterior chamber depth data, lens shape data representing the shape of the crystalline lens (lens curvature, lens thickness, etc.), corneal shape data representing the shape of the cornea (corneal radius of curvature, corneal thickness, etc.), etc. There is. At least a portion of the intraocular parameters 212A may be replaced with actual measured values (or values obtained from actual measured values) of the eye E to be examined. Actual measured values (for example, eye refractive power, corneal shape parameters, and axial length) of the eye E to be examined are acquired by the ophthalmological apparatus 1000 or an external device. In some embodiments, the above parameters are obtained from an electronic medical record system, a medical image archiving system, an external device, or the like.

Furthermore, the storage unit 212 stores various programs and data for operating the ophthalmologic apparatus.

(Optical system position acquisition unit 213)
The optical system position acquisition unit 213 is installed in the ophthalmological apparatus 1000 and acquires the current position of the apparatus optical system described above for optically acquiring data of the eye E to be examined.

For example, the optical system position acquisition unit 213 receives information representing the details of movement control of the moving mechanism 200 from the main control unit 211, and acquires the current position of the apparatus optical system shown in FIG. In this case, the main control unit 211 controls the moving mechanism 200 at a predetermined timing (at the time of device startup, patient information input, etc.) to move the device optical system to a predetermined initial position. From then on, each time the main control unit 211 controls the moving mechanism 200, it records the details of the control. Thereby, a history of control details can be obtained. The optical system position acquisition unit 213 refers to this history to acquire the control contents up to the present time, and determines the current position of the apparatus optical system based on the control contents.

In some embodiments, each time the main control unit 211 controls the moving mechanism 200, the control details are transmitted to the optical system position acquisition unit 213. The optical system position acquisition unit 213 sequentially obtains the current position of the apparatus optical system each time it receives the control content.

In some embodiments, the optical system position acquisition unit 213 includes a position sensor that detects the position of the device optical system.

The main control unit 211 can control the moving mechanism 200 based on the current position acquired by the optical system position acquisition unit 213 and a movement target position determined by the data processing unit 225, which will be described later. Thereby, the device optical system can be moved to the movement target position. For example, the main control unit 211 calculates the difference between the current position and the movement target position. This difference value is, for example, a vector value whose starting point is the current position and whose end point is the movement target position. This vector value is, for example, a three-dimensional vector value expressed in an XYZ coordinate system.

(Arithmetic processing unit 220)
The arithmetic processing section 220 includes an eye refractive power calculation section 221 , a corneal shape calculation section 222 , an image forming section 224 , and a data processing section 225 .

The functions of the arithmetic processing unit 220 are realized by one or more processors. In this case, a program that implements the functions of the arithmetic processing unit 220 is stored in a storage device or the like (storage unit 212), and one or more processors execute processing according to the corresponding program.

(Eye refractive power calculation unit 221)
The eye refractive power calculation unit 221 calculates a ring image (pattern image) obtained by the imaging device 59 receiving the return light of the ring-shaped light beam (ring-shaped measurement pattern) projected onto the fundus Ef by the reflex measurement projection system 6. ). For example, the eye refraction power calculation unit 221 calculates the center of gravity of the ring image from the brightness distribution in the image in which the obtained ring image is drawn, and calculates the brightness distribution along a plurality of scanning directions extending radially from this center of gravity. , identify the ring image from this brightness distribution. Next, the eye refractive power calculation unit 221 calculates an approximate ellipse of the identified ring image, and substitutes the major axis and minor axis of this approximate ellipse into a known formula to calculate the spherical power, astigmatic power, and astigmatic axis angle (eye Calculate the refractive power). Alternatively, the eye refractive power calculation unit 221 can calculate the parameters of the eye refractive power based on the deformation and displacement of the ring image with respect to the reference pattern.

(Cornea shape calculation unit 222)
The corneal shape calculation unit 222 analyzes the keratoring image obtained when the image sensor 59 receives the return light of the ring-shaped light beam projected onto the cornea Cr of the eye E by the keratometry system 3. Corneal shape information of E is calculated.

The corneal shape information includes, for example, any parameter value representing the shape of the cornea that can be measured using a known ophthalmological device. Typically, the corneal shape information includes the radius of curvature (curvature), the direction of the strong principal meridian, the radius of curvature (in degrees) along the strong principal meridian, the direction of the weak principal meridian, the radius of curvature (in degrees) along the weak principal meridian, It may include any of ellipticity, eccentricity, oblateness, topography including irregular astigmatism, aberration information using Zernike polynomials, etc.

For example, the corneal shape calculation unit 222 calculates the radius of corneal curvature of the strong principal meridian and weak principal meridian of the anterior surface of the cornea by analyzing the obtained keratoring image, and uses parameters representing the shape of the cornea based on the radius of corneal curvature. Calculate. The corneal shape calculation unit 222 calculates a corneal radius of curvature by performing arithmetic processing on the obtained keratoring image, and calculates corneal refractive power, corneal astigmatism degree, and corneal astigmatism axis angle from the calculated corneal radius of curvature. can do.

(Image forming unit 224)
The image forming unit 224 forms image data of a tomographic image of the fundus Ef based on the signal detected by the detector 125. That is, the image forming unit 224 forms image data of the eye E to be examined based on the detection result of the interference light LC by the interference optical system. This processing includes processing such as filter processing and FFT (Fast Fourier Transform), similar to conventional spectral domain type OCT. The image data acquired in this way is a data set that includes a group of image data formed by imaging reflection intensity profiles in a plurality of A lines (paths of each measurement light LS in the eye E). be.

To improve image quality, multiple data sets collected by scanning the same pattern multiple times can be overlapped (averaged).

For example, the functions of the image forming section 224 are realized by an image forming processor. In this case, a program that implements the functions of the image forming section 224 is stored in a storage device or the like (storage section 212), and the image forming processor executes processing according to the corresponding program.

(Data processing unit 225)
The data processing unit 225 performs various data processing (image processing) and analysis processing on the tomographic image formed by the image forming unit 224. For example, the data processing unit 225 executes correction processing such as image brightness correction and dispersion correction. Further, the data processing unit 225 performs various image processing and analysis processing on images (anterior segment images, etc.) obtained using the anterior segment observation system 5.

For example, the data processing unit 225 performs a predetermined analysis process on the detection result of interference light obtained by OCT measurement or the OCT image formed based on the detection result. The predetermined analysis process includes identifying a predetermined region (tissue, lesion) in the eye E; calculating the distance (interlayer distance), area, angle, ratio, and density between the specified regions; and using a specified calculation formula. identification of the shape of a predetermined part; calculation of these statistical values; calculation of the distribution of measured values and statistical values; and image processing based on the results of these analysis processes. Predetermined tissues include blood vessels, optic disc, retina, fovea, macula, and the like. Predetermined lesions include vitiligo, hemorrhage, and the like.

The data processing unit 225 can form volume data (voxel data) of the eye E to be examined by performing known image processing such as interpolation processing that interpolates pixels between tomographic images. When displaying an image based on volume data, the data processing unit 225 performs rendering processing on the volume data to form a pseudo three-dimensional image when viewed from a specific viewing direction.

As shown in FIG. 5, the data processing section 225 includes an alignment processing section 350 and a tracking processing section 360.

The alignment processing unit 350 performs data processing to align the device optical system with respect to a characteristic region in the anterior segment (for example, the center of the pupil) based on two or more captured images obtained by the anterior segment camera 300. I do. After the alignment based on the processing result of the alignment processing unit 350 is completed, the tracking processing unit 360 continues to align the apparatus optical system with respect to the eye E by deflection control of the optical scanner 88 ( Perform data processing for (perform positioning in a broad sense). The tracking processing unit 360 identifies the retina incidence position where the measurement light LS is incident from the anterior segment image, and performs data processing for controlling the optical scanner 88 based on the displacement of the retina incidence position with respect to the reference position on the retina. The retinal incident position is a position where the measurement light LS is incident on a predetermined layer region (for example, any layer from the internal limiting membrane to the retinal pigment epithelial layer) in the retina (fundus Ef). The retina incident position may be a position where the measurement light LS is incident on the choroid.

(Alignment processing unit 350)
As shown in FIG. 6, the alignment processing unit 350 includes an image correction unit 351, a Purkinje image identification unit 352, a Purkinje image position identification unit 353, a pupil center identification unit 354, a pupil center position identification unit 355, and a movement and a target position determining section 356.

(Image correction unit 351)
The image correction unit 351 corrects distortion of the photographed image obtained by the anterior segment camera 300. The image correction unit 351 can correct distortion of the photographed image based on the aberration information stored in the storage unit 212. This processing is performed, for example, by a known image processing technique based on correction coefficients for correcting distortion aberration. Note that if the optical system of the anterior segment camera 300 gives a sufficiently small distortion to the captured image, the aberration information and image correction unit 351 may not be provided.

(Purkinje statue identification unit 352)
The main control unit 211 turns on the alignment light source 21, for example. As a result, the alignment light beam is projected onto the anterior segment of the eye, forming a Purkinje image. The Purkinje image is formed at a position deviated from the corneal vertex in the axial direction (Z direction) by a distance of one half of the radius of corneal curvature.

The anterior segment of the eye onto which the alignment light beam is projected is photographed substantially simultaneously by the two anterior segment cameras 300. The two captured images acquired substantially simultaneously by the two anterior segment cameras 300 are corrected by the image correction unit 351 as necessary, and then input to the Purkinje image identification unit 352.

The Purkinje image identifying unit 352 identifies a Purkinje image (an image region corresponding to the Purkinje image) by analyzing each of the two captured images. This identification processing includes, for example, threshold processing regarding pixel values in order to search for a bright spot (high-intensity pixel) corresponding to a Purkinje image, as in the conventional art. Thereby, an image area in the photographed image corresponding to the Purkinje image is specified.

The Purkinje image specifying unit 352 can determine the position of a representative point in the image area corresponding to the Purkinje image. The representative point may be, for example, the center point or center of gravity of the image area. In this case, the Purkinje image identifying unit 352 can, for example, find an approximate circle or an approximate ellipse around the periphery of the image area, and find the center or center of gravity of the approximate circle or approximate ellipse.

(Purkinje image position identification unit 353)
The Purkinje image position specifying section 353 specifies the position of the Purkinje image specified by the Purkinje image specifying section 352 based on the information input from the Purkinje image specifying section 352. The position of the Purkinje image may include at least a position in the X direction (X coordinate value) and a position in the Y direction (Y coordinate value), and may also include a position in the Z direction (Z coordinate value).

That is, the Purkinje image identifying unit 352 identifies the Purkinje image for each of the two captured images (the first captured image and the second captured image) acquired using the two anterior segment cameras 300. Here, the two photographed images are images acquired by photographing from a direction different from the optical axis of the objective lens 51. When the XY alignment is substantially correct, the Purkinje image depicted in the two captured images is formed on the optical axis of the objective lens 51.

Since the angle of view of the two anterior segment cameras 300 (the angle with respect to the optical axis of the objective lens 51) is known, and the imaging magnification is also known, the position of the Purkinje image in the first captured image and the position of the Purkinje image in the second captured image are known. Based on the position of the Purkinje image, the relative position (three-dimensional position in real space) of the Purkinje image formed in the anterior segment with respect to the ophthalmological apparatus 1000 (anterior segment camera 300) can be determined.

In addition, the eye to be examined The relative position between the pupil of the eye and the Purkinje image formed in the anterior segment of the eye can be determined.

(Pupillary center identification unit 354)
The pupil center specifying unit 354 analyzes each captured image obtained by the anterior segment camera 300 or the image whose distortion has been corrected by the image correcting unit 351, thereby identifying a point corresponding to a predetermined feature point of the anterior segment. The position in the photographed image is specified. In this embodiment, the pupil center of the eye E to be examined is specified. Note that the center of gravity of the pupil may be determined as the pupil center. Further, it may be configured to specify feature points other than the pupil center (pupil center of gravity).

The pupil center identifying unit 354 identifies an image region (pupil region) corresponding to the pupil of the eye E, based on the distribution of pixel values (luminance values, etc.) of the photographed image. Generally, the pupil is expressed with lower brightness than other parts, so the pupil area can be identified by searching for a low brightness image area. At this time, the pupil area may be specified by considering the shape of the pupil. In other words, the pupil area can be configured to be identified by searching for a substantially circular and low-luminance image area.

Next, the pupil center specifying unit 354 specifies the center position of the specified pupil area. Since the pupil is approximately circular as described above, it is possible to specify the outline of the pupil area, specify the center position of an approximate ellipse of this outline, and set this as the pupil center. Alternatively, the center of gravity of the pupil area may be determined and the position of the center of gravity may be set as the center of the pupil.

Note that even when other feature points are applied, it is possible to specify the position of the feature point based on the distribution of pixel values of the captured image, as described above.

(Pupillary center position identification unit 355)
The pupil center position specifying unit 355 determines the position of the subject's eye based on the positions (and imaging magnification) of the two anterior segment cameras 300 and the positions of the pupil centers in the two captured images specified by the pupil center specifying unit 354. Identify the three-dimensional position of the center of E's pupil.

For example, as disclosed in Patent Document 1 (Japanese Unexamined Patent Publication No. 2013-248376), the distance (baseline length) between the two anterior eye cameras 300 is set to "B", and the two anterior eye cameras 300 The distance between the baseline and the center of the pupil of the subject's eye E (imaging distance) is "H", and the distance between each anterior segment camera 300 and its screen plane (screen distance) is "f". . , the pixel resolution is Δp, the resolution of the captured image by the anterior segment camera 300 is expressed by the following equation.

Resolution in xy direction (plane resolution): Δxy=H×Δp/f
Resolution in the z direction (depth resolution): Δz=H×H×Δp/(B×f)

The pupil center position specifying unit 355 uses a known trigonometry method that takes into account the positional relationship between the positions of the two anterior eye cameras 300 (which are known) and the positions corresponding to the pupil centers in the two captured images. By applying this method, the three-dimensional position of the center of the pupil as a characteristic part is calculated.

(Movement target position determination unit 356)
The moving target position determination unit 356 determines the moving target position of the apparatus optical system based on the Purkinje image position specified by the Purkinje image position specifying unit 353 and the pupil center position specified by the pupil center position specifying unit 355. decide. For example, the movement target position determining unit 356 determines the difference between the specified Purkinje image position and the specified pupil center position, and determines the movement target position so that the calculated difference satisfies predetermined alignment completion conditions. do.

The main control unit 211 controls the movement mechanism 200 based on the movement target position determined by the movement target position determination unit 356.

(Tracking processing unit 360)
As shown in FIG. 7, the tracking processing section 360 includes an eyeball model generation section 361 and an analysis section 362. The eyeball model generation section 361 includes a parameter calculation section 361A and a model generation section 361B. The analysis unit 362 includes a corneal incident position specifying unit 362A, a retina incident position specifying unit 362C, and a scan processing unit 362D.

(Eyeball model generation unit 361)
The eyeball model generation unit 361 creates a three-dimensional eyeball model of the eye E to be examined based on the intraocular parameters 212A. The eyeball model generation unit 361 can obtain parameters that can be calculated based on the results of keratometry, eye refractive power measurement (reflex measurement), or OCT measurement among the parameters included in the intraocular parameters 212A. be.

The eyeball model generation unit 361 can obtain the above size parameters, shape parameters, and optical parameters.

As mentioned above, the size parameter represents the size of a portion or the entire eye. Size parameters representing a part of the eye include corneal thickness, crystalline lens thickness, anterior chamber depth (distance between the posterior surface of the cornea and the anterior surface of the crystalline lens), retinal thickness, and pupil diameter. An example of a size parameter representing the entire eye is the axial length.

As mentioned above, the shape parameter represents the shape of the eye region. The site of the eye may be, for example, the anterior surface of the cornea, the posterior surface of the cornea, the anterior surface of the crystalline lens, the posterior surface of the crystalline lens, the surface of the retina, a predetermined layer of the retina, the choroid, the pupil (iris), and the like. Further, parameters representing the shape include a curvature at a predetermined point, a curvature distribution in a predetermined range, and an inclination angle.

As mentioned above, optical parameters describe the optical function of a region of the eye. Optical parameters include the refractive power (sphericity, degree of astigmatism, astigmatic axis, etc.) of the cornea (anterior surface, posterior surface) and the refractive power of the crystalline lens (anterior surface, posterior surface). Further, the optical parameters may include any parameters related to aberrations such as chromatic aberration, spherical aberration, coma aberration, astigmatism, curvature of field, and distortion. Further, the optical parameters may include any parameters related to the optical properties of the eye region, such as the refractive index, reflectance, dispersion characteristics, and polarization characteristics of the eye region.

Note that the parameters included in the intraocular parameters 212A may be corrected based on data obtained by keratometry, eye refractive power measurement, or OCT measurement, and then applied as new parameters constituting the eyeball model.

(Parameter calculation unit 361A)
The parameter calculation unit 361A obtains parameters regarding the eye E to be examined by analyzing OCT data (data set) obtained by the OCT optical system 8. The OCT data set represents the morphology of a three-dimensional region of the eye E to be examined, including a range from the front surface of the cornea to the surface of the retina. That is, this three-dimensional region corresponds to the measurement region by OCT, and the image obtained as the OCT data set depicts the morphology of each part of the eye E in this three-dimensional region.

For example, the parameter calculation unit 361A, as an intraocular distance calculation unit, calculates one or more intraocular distances in the eye E based on the detection result of the interference light LC obtained by the OCT optical system 8. The one or more intraocular distances include axial length (distance from the corneal apex to the internal limiting membrane), corneal thickness, anterior chamber depth, crystalline lens thickness, vitreous cavity length, retinal thickness, choroidal thickness, and the like.

FIG. 8 shows an explanatory diagram of parameters according to the embodiment. FIG. 8 schematically represents the cross-sectional structure of the eyeball.

For example, as shown in FIG. 8, the parameters include the refractive index of each site within the eye, the intraocular distance as a size parameter, and the radius of curvature as a shape parameter. The refractive index includes the refractive index n1 of the cornea, the refractive index n2 of the aqueous humor, the refractive index n3 of the crystalline lens, and the refractive index n4 of the vitreous humor. Intraocular distances include Center Corneal Thickness (CCT), Anterior Chamber Depth (ACD) equivalent to the distance from the back surface of the cornea to the front surface of the crystalline lens, Lens Thickness (LT), and Vitreous Thickness (LT). Chamber Depth) VCD, etc. The radius of curvature includes the radius of curvature of the anterior surface of the cornea (R1), the radius of curvature of the posterior surface of the cornea (R1), and the radius of curvature of the posterior surface of the cornea (R1). of the cornea) R2, Radius of curvature of the anterior surface of the crystalline lens and the radius of curvature of the posterior surface of the lens (R4).

As the above-mentioned refractive index, a parameter (intraocular parameter 212A) of an eyeball model such as a known model eye can be used. The parameter calculation unit 361A can calculate at least one of the size parameter and shape parameter described above.

An example of a process for calculating a size parameter from an OCT data set will be described. First, the parameter calculation unit 361A identifies the target region of the eye E to be examined. This processing is performed by analyzing pixel values of the OCT data set, and includes known image processing such as filtering, thresholding, edge detection, etc. Typically, when determining corneal thickness, the anterior and posterior corneal surfaces are identified; when determining lens thickness, the anterior and posterior surfaces of the lens are identified; and when determining anterior chamber depth, the posterior corneal surface is identified. and the front surface of the crystalline lens are specified, the retinal surface and the back surface are specified when the retinal thickness is to be determined, and the edge of the iris (pupillary boundary) is specified when the pupil diameter is to be determined. When determining the axial length from an OCT data set, the anterior surface of the cornea and the retinal surface (predetermined layer tissue in the retina) are specified.

Next, the parameter calculation unit 361A identifies two or more feature points that will be the size measurement positions among the identified parts. This processing is performed by analyzing the pixel position and/or pixel value of the identified region, and includes known image processing such as pattern matching, differential calculation (curvature calculation), filter processing, threshold processing, and edge detection. including. When determining the corneal thickness, the apex of the anterior surface of the cornea (corneal apex) and the apex of the posterior corneal surface are identified. The vertex of the anterior surface of the cornea is specified, for example, by shape analysis of the anterior surface of the cornea, or by the Z coordinate value of a pixel on the anterior surface of the cornea. The vertex of the posterior corneal surface is, for example, identified as the intersection of the posterior corneal surface and a straight line passing through the corneal vertex and extending in the Z direction, and is identified by shape analysis of the posterior corneal surface, or by the Z coordinate value of a pixel on the posterior corneal surface. Ru. Similar processing is performed for other parameters as well.

Further, the parameter calculation unit 361A calculates the size based on the two or more identified feature points. When determining the corneal thickness, the distance between the specified vertex of the anterior corneal surface and the vertex of the posterior corneal surface is determined. This distance may be expressed, for example, by the number of pixels between two vertices, or may be a value obtained by converting this number of pixels into a real space distance based on the imaging magnification. Such a conversion process to a real space distance can be performed by, for example, the method disclosed in Japanese Patent Application Laid-Open No. 2016-43155.

An example of processing for calculating shape parameters from an OCT data set will be described. First, the parameter calculation unit 361A identifies the target region of the eye E to be examined. This process may be similar to that for the size parameter. Next, the parameter calculation unit 361A calculates shape parameters based on the identified region. For example, when determining the curvature at a feature point, the feature point can be identified in the same manner as the size parameter, and the curvature at this feature point can be calculated based on the shape of the vicinity of this feature point. When determining the curvature distribution in a predetermined range, similar processing may be performed for each point within the range. When determining the inclination angle, differential processing can be performed based on the position (point) and the shape of its vicinity.

An example of processing for calculating optical parameters from an OCT data set will be described. The OCT data set represents the form (shape, size, etc.) of the part of the eye E to be examined. As for optical parameters that can be calculated only from the shape of the site, it is possible to calculate the optical parameters using a known formula that associates the shape or size of the site with the optical parameters. In addition, for optical parameters that cannot be calculated solely from the morphology of the body part, it is possible to use known mathematical formulas while referring to other necessary values (measured values or standard values such as model eye data). be. For example, when determining the refractive power of a crystalline lens, the refractive index of the crystalline lens and the refractive index of a portion adjacent thereto can be referred to. It is also possible to obtain the refractive power by performing ray tracing assuming paraxial approximation.

In addition, the parameters or intraocular parameters 212A calculated by the parameter calculation unit 361A include the center position of rotation of the eye (or the eye E), the corneal GRIN (Gradient Index) structure (refractive index distribution structure), and the crystalline lens GRIN structure ( refractive index distribution structure), curvature of the fundus (retina), refractive index wavelength dispersion, etc. The refractive index wavelength dispersion may include the refractive index wavelength dispersion of each of the cornea, aqueous humor, crystalline lens, and vitreous body.

(Model generation unit 361B)
The model generation unit 361B creates a three-dimensional eyeball model of the eye E to be examined using the parameters calculated by the parameter calculation unit 361A. The model generation unit 361B can create a three-dimensional eyeball model of the eye E to be examined using at least one of the intraocular parameter 212A, the eye refractive power, the corneal shape information, and the intraocular distance.

The model generation unit 361B associates each of the parameters calculated by the above units with a corresponding part in the eyeball model. This process is executed, for example, by associating the parameters with the parts and feature points specified in the process of calculating the parameters. For example, parameters representing the shape of the anterior surface of the cornea (curvature, curvature distribution, etc.) are associated with the anterior surface of the cornea in the eyeball model. Further, a parameter representing the axial length of the eye is associated with the front surface of the cornea (corneal apex, etc.) and the retinal surface (fovea, etc.) in the eyeball model. The same applies to other parameters.

(Analysis unit 362)
In addition to the analysis processing described above, the analysis unit 362 performs processing for specifying (estimating) the incident position of the measurement light LS in a site within the eye (eg, cornea, retina).

FIG. 9 shows an explanatory diagram of the operation of the analysis unit 362 according to the embodiment. FIG. 9 schematically represents the cross-sectional structure of the eye E to be examined.

In the above alignment process, the main control section 211 controls the movement mechanism 200 based on the movement target position determined by the movement target position determining section 356. Thereby, from the anterior segment image of the eye E to be examined, it becomes possible to specify the intersection of the measurement optical axis (scan center) and the cornea Cr as the corneal incident position Pc of the measurement light LS. The corneal incident position Pc is a position where the measurement light LS is incident on the anterior surface of the cornea (in some embodiments, the posterior surface of the cornea). Furthermore, by performing ray tracing processing using the eyeball model generated by the eyeball model generation unit 361 on the measurement light LS that has entered the corneal incidence position Pc, the retina incidence position Pr where the measurement light LS is incident on the retina is determined. It is possible to specify

That is, the analysis unit 362 specifies the corneal incident position on the cornea Cr at which the measurement light LS is incident from the anterior segment image of the eye E, and determines the incidence of the measurement light LS on the retina corresponding to the specified corneal incident position. Identify the retinal incidence position. The analysis unit 362 can specify the retina incidence position by performing known ray tracing processing on the measurement light LS that has entered the corneal incidence position.

(Cornea incidence position identification unit 362A)
The corneal incident position specifying unit 362A specifies the incident position of the measurement light LS on the cornea Cr from the anterior segment image of the eye E to be examined. When the alignment of the optical system with respect to the eye E is performed based on the anterior segment image, the corneal incident position specifying unit 362A can specify the corneal incident position using the alignment information. For example, the corneal incident position specifying unit 362A can specify the intersection of the optical axis of the apparatus optical system and the cornea Cr of the eye E to be examined as the corneal incident position. The anterior segment image may be any one of two or more captured images obtained by the anterior segment camera 300.

In this embodiment, the corneal incident position specifying unit 362A determines the measurement light LS from the three-dimensional position of the Purkinje image specified by the Purkinje image position specifying unit 353 from two or more captured images acquired by the anterior segment camera 300. Identify the corneal incidence position.

(Retinal incidence position identification unit 362C)
The retina incidence position specifying unit 362C specifies the incident position at which the measurement light LS, which has entered the cornea incidence position specified by the cornea incidence position specifying unit 362A, enters the retina. For example, the retina incident position specifying unit 362C specifies the retina incident position by performing known ray tracing processing on the measurement light LS that has entered the corneal incident position. In the ray tracing process, using the eyeball model generated by the eyeball model generation unit 361, a known relational expression derived from Snell's law is sequentially applied from the retina entrance position to the front surface of the cornea, the back surface of the cornea, the front surface of the crystalline lens, and the back surface of the crystalline lens. By applying this method, the incident position of the light ray on the retina is specified.

(Scan processing unit 362D)
The scan processing unit 362D generates control information to be fed back to the optical scanner 88 so that a predetermined position on the retina becomes the scan center based on the retina incidence position specified by the retina incidence position identification unit 362C. The control information includes at least one of the scan width, scan speed, and scan center offset value of the galvano scanner that constitutes the optical scanner 88. Examples of the predetermined position on the retina include a reference position, a retinal incident position, a position between the reference position and the retinal incident position, a lesion site, a characteristic site, a blood vessel, a position specified by the user, and the like.

The main control unit 211 controls the deflection operation of the optical scanner 88 by controlling the optical scanner 88 based on the feedback control information. Tracking control becomes possible by repeating the above feedback control for each one or more OCT scans. For example, the main control unit 211 sets the scan start position in synchronization with the scan start trigger for each one or more line scans (B scans) so that a predetermined observation site (for example, the fovea) can be observed. Updated by feedback control. Alternatively, for example, the main control unit 211 updates the scan start position by feedback control in synchronization with the B-scan start trigger so that the centers of the C-scan images during the 3D scan are at the same position.

For example, the scan processing unit 362D repeats the ray tracing simulation (ray tracing process) while changing the incident angle of the measurement light LS on the cornea Cr by a minute angle until the above-mentioned retinal incident position converges on a predetermined position on the retina. The scan processing unit 362D generates control information for the optical scanner 88 so that the angle of incidence when the retina incidence position converges on a predetermined position on the retina becomes the scan center angle. In some embodiments, an eyeball model to which parameters representing the optical characteristics of the eye E to be examined are applied is used in the ray tracing simulation.

For example, the scan processing unit 362D specifies the amount of change in the angle of incidence of the measurement light LS on the cornea Cr from table information or a predetermined function based on the displacement of the retinal incident position to be the reference position on the retina, and the specified change Control information for the optical scanner 88 is generated based on the amount. In some embodiments, the amount of change in the angle of incidence of the measurement light LS is specified according to table information or a function whose variables are parameters representing the optical characteristics of the eye E to be examined.

The data processing unit 225 having the above configuration includes, for example, a processor, a RAM, a ROM, a hard disk drive, and the like. A computer program that causes a processor to execute the above-described processing is stored in advance in a storage device such as a hard disk drive.

(Display section 270, operation section 280)
The display unit 270 serves as a user interface unit and displays information under the control of the control unit 210. The display section 270 includes the display section 10 shown in FIG. 1 and the like.

The operation unit 280 is used as a user interface unit to operate the ophthalmological apparatus. The operation unit 280 includes various hardware keys (joystick, buttons, switches, etc.) provided on the ophthalmologic apparatus. Further, the operation unit 280 may include various software keys (buttons, icons, menus, etc.) displayed on the touch panel display screen 10a.

At least a portion of the display section 270 and the operation section 280 may be integrally configured. A typical example thereof is a touch panel type display screen 10a.

(Communication Department 290)
The communication unit 290 has a function for communicating with an external device (not shown). The communication unit 290 includes a communication interface depending on the type of connection with an external device. An example of an external device is a spectacle lens measuring device for measuring the optical properties of a lens. The spectacle lens measuring device measures the power of spectacle lenses worn by the subject and inputs this measurement data to the ophthalmological device 1000. Further, the external device may be any ophthalmological device, a device that reads information from a recording medium (reader), a device that writes information to a recording medium (writer), or the like. Further, the external device may be a hospital information system (HIS) server, a DICOM (Digital Imaging and Communication in Medicine) server, a doctor terminal, a mobile terminal, a personal terminal, a cloud server, etc. The communication unit 290 may be provided in the processing unit 9, for example.

The OCT optical system 8 is an example of an "optical system" according to the embodiment. The anterior segment camera 300 is an example of the "acquisition unit" and the "imaging unit" according to the embodiment. The alignment light projection system 2 is an example of an "alignment optical system" according to the embodiment. The keratometry system 3 is an example of a "corneal shape measurement optical system" according to the embodiment. The reflex measurement projection system 6 and the reflex measurement light receiving system 7 are an example of the "refractive power measurement optical system" according to the embodiment. The eye refractive power calculation unit 221 is an example of a “refractive power value calculation unit” according to the embodiment. The keratometry system 3 is an example of a "corneal shape measurement optical system" according to the embodiment. The reflex measuring optical system (the reflex measuring projection system 6 and the reflex measuring light receiving system 7) is an example of the "refractive power measuring optical system" according to the embodiment. The eye refractive power calculation unit 221 is an example of a “refractive power value calculation unit” according to the embodiment. The parameter calculation unit 361A is an example of an “intraocular distance calculation unit” according to the embodiment.

<Operation example>
The operation of the ophthalmologic apparatus 1000 according to the embodiment will be described.

(First operation example)
FIG. 10 shows a first operation example of the ophthalmologic apparatus 1000. FIG. 10 depicts a flow diagram of an example operation of the ophthalmologic apparatus 1000. The storage unit 212 stores a computer program for implementing the processing shown in FIG. The main control unit 211 executes the processing shown in FIG. 10 by operating according to this computer program.

(S1: Obtain corneal shape parameters, eye refractive power, and axial length)
First, the ophthalmological apparatus 1000 acquires the corneal shape parameter of the eye E to be examined, the ocular refractive power of the eye E to be examined, and the axial length. Corneal shape parameters and the like are acquired from an external device such as an external ophthalmological device or an electronic medical record system.

In some embodiments, after the alignment of the optical system with respect to the eye E is completed, corneal shape parameters and the like are acquired by measurements on the eye E. The corneal shape parameters are obtained by performing keratometry on the eye E to be examined. The eye refractive power is obtained by performing reflex measurement on the eye E to be examined. The axial length is obtained, for example, by performing OCT measurement on the eye E to be examined. Although a case will be described below in which the axial length is acquired as an intraocular parameter, intraocular parameters other than the axial length may be acquired.

When performing keratometry, the main control unit 211 causes the liquid crystal panel 41 to display a pattern indicating a fixation target at a display position corresponding to a desired fixation position. Thereby, the subject's eye E is caused to gaze at the desired fixation position. Thereafter, the main control unit 211 turns on the keratoring light source 32. When light is output from the keratoring light source 32, a ring-shaped light beam for corneal shape measurement is projected onto the cornea Cr of the eye E to be examined. The corneal shape calculation unit 222 calculates a corneal radius of curvature by performing arithmetic processing on the image acquired by the image sensor 59, and calculates corneal refractive power, corneal astigmatism degree, and corneal astigmatism axis from the calculated corneal radius of curvature. Calculate the angle. In the control unit 210, the calculated corneal refractive power and the like are stored in the storage unit 212.

When performing reflex measurement, the main control unit 211 projects a ring-shaped measurement pattern light beam for refractive power measurement onto the eye E to be examined, as described above. A ring image based on the return light of the measurement pattern light flux from the eye E to be examined is formed on the imaging surface of the imaging element 59. The main control unit 211 determines whether a ring image based on the return light from the fundus Ef detected by the image sensor 59 has been acquired. For example, the main control unit 211 detects the position (pixel) of the edge of the image based on the return light detected by the image sensor 59, and determines whether the width of the image (difference between the outer diameter and the inner diameter) is greater than or equal to a predetermined value. Determine whether or not. Alternatively, the main control unit 211 determines whether a ring image can be obtained by determining whether a ring can be formed based on points (images) having a predetermined height (ring diameter) or more. Good too.

When it is determined that the ring image has been acquired, the eye refractive power calculation unit 221 analyzes the ring image based on the return light of the measurement pattern light beam projected onto the eye E using a known method, and calculates the temporary spherical power S and Find a temporary astigmatic power C. The main control unit 211 adjusts the reflex measurement light source 61, focusing lens 74, and fixation unit 40 (liquid crystal panel 41) to an equivalent spherical power (S+C/2) based on the obtained temporary spherical power S and astigmatic power C. (the position corresponding to the temporary far point). The main control unit 211 further moves the fixation unit 40 (liquid crystal panel 41) from that position to the cloud position, and then controls the reflex measurement projection system 6 and the reflex measurement light receiving system 7 to create a ring image as the main measurement. Let them get it again. The main control unit 211 causes the eye refractive power calculation unit 221 to calculate the spherical power, astigmatic power, and astigmatic axis angle from the ring image analysis result obtained in the same manner as described above and the movement amount of the focusing lens 74.

Further, the eye refractive power calculation unit 221 calculates a position corresponding to the far point of the eye E to be examined (a position corresponding to the far point obtained by the main measurement) from the obtained spherical power and astigmatic power. The main control unit 211 moves the liquid crystal panel 41 to a position corresponding to the determined far point. In the control unit 210, the position of the focusing lens 74, the calculated spherical power, etc. are stored in the storage unit 212.

When it is determined that a ring image cannot be obtained, the main control unit 211 takes into account the possibility that the eye has strong refractive error, and moves the reflex measurement light source 61 and focusing lens 74 to the negative power side (for example, -10D), move it to the positive power side (for example, +10D). The main control unit 211 controls the reflex measurement light receiving system 7 to detect a ring image at each position. If it is determined that a ring image cannot be obtained even after that, the main control unit 211 executes predetermined measurement error processing. At this time, the operation of the ophthalmologic apparatus 1000 may proceed to the next step. In the control unit 210, information indicating that no reflex measurement result was obtained is stored in the storage unit 212.

When performing OCT measurement, the main control unit 211 moves the fixation unit 40 (liquid crystal panel 41) from the fog position to the focus position. In some embodiments, the focus position is the position of the equivalent spherical power (S+C/2) identified in step S3, or the position where the intensity of the interference signal is maximized from the position of the equivalent spherical power (S+C/2). This is the position where the focus has been adjusted.

Next, the main control unit 211 turns on the OCT light source 101 and controls the optical scanner 88 to scan a predetermined region of the fundus Ef (for example, a region including the macular region) with the measurement light LS.

The main control unit 211 causes the parameter calculation unit 361A to calculate the axial length of the eye E to be examined. The parameter calculation unit 361A specifies a position corresponding to the corneal apex and a position corresponding to the fundus from the peak position of the detection signal of the acquired interference light LC, and calculates the ocular axial length from the specified positions. The parameter calculation unit 361A may calculate the above parameters other than the axial length.

(S2: Generate eyeball model)
Next, the main control unit 211 generates a three-dimensional eyeball model of the eye E to be examined using the corneal shape parameter, the eye refractive power, and the axial length calculated by the parameter calculation unit 361A acquired in step S1. The unit 361B generates the information.

(S3: OCT measurement?)
The main control unit 211 determines whether or not to perform OCT measurement. For example, the main control unit 211 determines whether or not to perform OCT measurement based on the user's operation on the operation unit 280 or a preset operation mode.

When it is determined that OCT measurement is to be performed (S3: Y), the operation of the ophthalmologic apparatus 1000 moves to step S4. When it is determined that OCT measurement is not to be performed (S3: N), the operation of the ophthalmologic apparatus 1000 is ended (END).

(S4: Within the default range?)
In step S3, when it is determined to perform OCT measurement (S3: Y), the main control unit 211 performs the above alignment process.

In the alignment process, the main control unit 211 turns on the alignment light source 21. Furthermore, the main control unit 211 controls the anterior segment camera 300 to substantially simultaneously photograph the anterior segment of the eye E to be examined, which is irradiated with the alignment light output from the alignment light source 21 . The main control unit 211 determines whether the displacement between the position of the device optical system acquired by the optical system position acquisition unit 213 and the movement target position determined by the alignment processing unit 350 is within a predetermined range as described above. Determine.

When it is determined that the displacement between the position of the apparatus optical system and the moving target position is within the predetermined range (S4: Y), the operation of the ophthalmologic apparatus 1000 moves to step S6. When it is determined that the displacement between the position of the apparatus optical system and the movement target position is not within the predetermined range (S4:N), the operation of the ophthalmologic apparatus 1000 moves to step S5.

(S5: relative movement)
When it is determined in step S4 that the displacement between the position of the apparatus optical system and the movement target position is not within the predetermined range (S4:N), the main control unit 211 controls the movement mechanism 200 to The apparatus optical system is moved relative to E by a predetermined step. After that, the operation of the ophthalmologic apparatus 1000 moves to step S4.

(S6: Start tracking with optical scanner)
When it is determined in step S4 that the displacement between the position of the apparatus optical system and the moving target position is within the predetermined range (S4: Y), the main control unit 211 controls whether the optical system shown in FIG. It is determined that it has been moved to the inspection position, and the reflex measurement light source 61, focusing lens 74, and fixation unit 40 (liquid crystal panel 41) are moved to the origin position (for example, a position corresponding to 0D) along their respective optical axes. move it to Here, the test position is a position where the test eye E can be tested within sufficient accuracy.

Next, the main control unit 211 causes the optical scanner 88 to start tracking processing. Details of step S6 will be described later.

(S7: OCT measurement)
The main control unit 211 moves the fixation unit 40 (liquid crystal panel 41) from the fog position to the focus position. In some embodiments, the in-focus position is a position corresponding to the equivalent spherical power (S+C/2) obtained in step S1, or a position where the intensity of the interference signal, etc. is maximum from the position of the equivalent spherical power (S+C/2). This is the position where the focus has been adjusted so that

Next, the main control unit 211 turns on the OCT light source 101 and controls the optical scanner 88 to scan a predetermined region of the fundus Ef (for example, a region including the macular region) with the measurement light LS.

The main control unit 211 can send the detection signal obtained by scanning with the measurement light LS to the image forming unit 224, and cause the image forming unit 224 to form a tomographic image of the fundus Ef from the obtained detection signal. Further, the main control unit 211 can display the formed tomographic image on the display unit 270. This is the end of the operation of the ophthalmologic apparatus 1000 (end).

FIG. 11 shows a flowchart of an example of the operation of step S6 in FIG. 10. The storage unit 212 stores a computer program for implementing the processing shown in FIG. 11. The main control unit 211 executes the processing shown in FIG. 11 by operating according to this computer program.

(S11: Identify corneal incidence position)
The main control unit 211 specifies the corneal incident position of the measurement light LS from the three-dimensional position of the Purkinje image specified by the Purkinje image position specifying unit 353 based on the captured image acquired by the anterior segment camera 300. 362A.

(S12: Identify the retinal incident position)
The main control unit 211 performs ray tracing processing using the eyeball model generated by the eyeball model generation unit 361 on the measurement light LS that has entered the corneal incidence position specified in step S11, thereby determining the retina incidence position. The retinal incident position specifying unit 362C is made to specify.

(S13: Calculate displacement)
The analysis unit 362 determines the displacement of the retinal incident position with respect to the reference position on the retina. The analysis unit 362 determines at least one of the displacement in the horizontal plane and the displacement in the vertical plane. The analysis unit 362 may obtain displacement within two planes that intersect with each other. The reference position may be specified by analyzing a tomographic image of the eye E obtained using the OCT optical system 8, or may be specified by the user using the operation unit 280. Reference positions include the fovea, the macula, the lesion, the optic disc, and blood vessels.

(S14: Optical scanner processing)
The main control unit 211 causes the scan processing unit 362D to generate control information to be fed back to the optical scanner 88 from the displacement between the reference position on the retina and the retinal incident position specified in step S13. Details of step S14 will be described later.

(S15: Control optical scanner)
The main control unit 211 controls the deflection operation of the optical scanner 88 based on the control information generated in the optical scanner process in step S14.

This is the end of the process in step S6 in FIG. 10 (end). For example, the main control unit 211 can execute the process shown in FIG. 11 for each one or more OCT scans. That is, tracking control becomes possible by repeating the above feedback control for each one or more OCT scans.

FIG. 12 shows a flowchart of an operation example of step S14 in FIG. 11. A computer program for implementing the process shown in FIG. 12 is stored in the storage unit 212. The main control unit 211 executes the processing shown in FIG. 12 by operating according to this computer program.

(S21: Obtain eyeball model)
For example, the main control unit 211 causes the retina incidence position specifying unit 362C to acquire an eyeball model (an eyeball model such as a known model eye) stored in advance in the storage unit 212.

(S22: Identify the retinal incident position)
Subsequently, the main control unit 211 causes the retina incidence position specifying unit 362C to specify the retina incidence position of the measurement light LS deflected by the optical scanner 88, as in step S12. That is, first, the corneal incident position specifying unit 362A determines the three-dimensional position of the Purkinje image specified by the Purkinje image position specifying unit 353 based on the two captured images acquired by the anterior segment camera 300, as in step S11. From this, the corneal incident position of the measurement light LS is specified. Subsequently, the retina incidence position identification unit 362C performs ray tracing processing using the eyeball model acquired in step S21 on the measurement light LS that has entered the cornea incidence position identified by the cornea incidence position identification unit 362A. By this, the retinal incident position is specified.

(S23: Calculate displacement ΔX, ΔY)
Next, the main control unit 211 calculates the displacement (displacement ΔX in the horizontal plane (displacement in the X-axis direction), displacement ΔY (displacement in the Y-axis direction) in the vertical plane) of the retinal incident position with respect to the reference position on the retina using an analysis unit. 362 to calculate. Although FIG. 13 shows the displacement ΔX in the horizontal plane due to the measurement light LS deflected around the pivot point Pv, which is an optically conjugate position with the optical scanner 88, the displacement ΔY in the vertical plane is also the same. be. The reference position is, for example, a position corresponding to the fovea specified from the tomographic image of the eye E acquired by the OCT optical system 8. For example, by associating the position of each part in the tomographic image with the position of each part in the eyeball model in advance, it is possible to specify the position in the eyeball model that corresponds to the part specified in the tomographic image. Thereby, the analysis unit 362 can specify the displacement (displacement in the X-axis direction, displacement in the Y-axis direction) of the retina incidence position with respect to the reference position.

(S24: Change incident angle)
In a minute region, since it is thought that there is a linear relationship between the amount of change in the angle of incidence and the displacement of the position on the retina, it is possible to estimate the amount of change in the angle of incidence from the displacement of the position on the retina. Therefore, the main control unit 211 changes the incident angle condition in the ray tracing process so that the incident angle of the measurement light LS deflected by the optical scanner 88 on the cornea Cr is changed by a predetermined small angle.

(S25: Identify the retina incidence position)
The retinal incident position specifying unit 362C specifies a new retinal incident position by performing ray tracing processing on the measurement light LS whose incident angle has been changed in the cornea Cr in step S24 in the same manner as in step S22.

(S26: Calculate displacement ΔX', ΔY')
Similarly to step S23, the main control unit 211 determines the displacement of the retinal incident position relative to the reference position on the retina (displacement ΔX' in the horizontal plane, displacement ΔY' in the vertical plane) with respect to the retinal incident position specified in step S25. ) is calculated by the analysis unit 362. In FIG. 13, the displacement ΔX' in the horizontal plane is illustrated, but the same applies to the displacement ΔY' in the vertical plane. The reference position is the same as the reference position in step S23.

(S27: Within the threshold?)
The main control unit 211 determines whether each of the displacements ΔX' and ΔY' calculated in step S26 is within a predetermined threshold value. The threshold value for displacement ΔX' and the threshold value for ΔY' may be the same value or may be different values.

When it is determined in step S27 that each of the displacements ΔX' and ΔY' is within a predetermined threshold value (S27: Y), the operation of the ophthalmologic apparatus 1000 moves to step S28. When it is determined in step S27 that each of the displacements ΔX' and ΔY' is not within the predetermined threshold (S27: N), the operation of the ophthalmologic apparatus 1000 moves to step S24. That is, steps S24 to S26 are repeated until each of the displacements ΔX' and ΔY' converges within the allowable range.

(S28: Generate control information for optical scanner)
When it is determined in step S27 that each of the displacements ΔX' and ΔY' is within the predetermined threshold (S27:Y), the main control unit 211 controls the measurement light LS so that the incident angle of the measurement light LS when converged is equal to the scan center angle. The scan processing unit 362D is made to generate control information for changing at least one of the scan width, scan speed, and offset value of the scan center of the optical scanner 88. The main control unit 211 controls the optical scanner 88 based on the control information generated by the scan processing unit 362D. This makes it possible to perform tracking control so that the center of the OCT image is at a predetermined position.

This completes the process of step S14 in FIG. 11 (end).

In the process of FIG. 12, the retinal incident position is specified using the eyeball model stored in advance in the storage unit 212, but the process according to the embodiment is not limited to this. For example, the retinal incident position may be specified using an eyeball model that includes intraocular parameters representing the optical characteristics of the eye E to be examined.

FIG. 14 shows a flowchart of an operation example of step S14 according to a modification of the first operation example. The storage unit 212 stores a computer program for implementing the processing shown in FIG. 14. The main control unit 211 executes the processing shown in FIG. 14 by operating according to this computer program.

(S31: Obtain measurement value)
The main control unit 211 causes the eyeball model generation unit 361 to acquire the corneal shape parameter of the eye E to be examined, the refractive power of the eye E, and the axial length of the eye E, as in step S1. The corneal shape parameters and the like are acquired by measuring the eye E to be examined, as described above. The corneal shape parameters are obtained by performing keratometry on the eye E to be examined. The eye refractive power is obtained by performing reflex measurement on the eye E to be examined. The axial length is obtained, for example, by performing OCT measurement on the eye E to be examined. Intraocular parameters other than the axial length may be acquired as the intraocular parameters.

(S32: Generate eyeball model)
Next, the main control unit 211 generates a three-dimensional eyeball model of the eye E to be examined using the corneal shape parameter, the eye refractive power, and the axial length calculated by the parameter calculation unit 361A acquired in step S31. The unit 361B generates the information.

(S33: Identify the retina incidence position)
Next, the main control unit 211 causes the retina incidence position identification unit 362C to specify the retina incidence position of the measurement light LS deflected by the optical scanner 88, as in step S22.

(S34: Calculate displacement ΔX, ΔY)
Next, the main control unit 211 causes the analysis unit 362 to calculate the displacement (displacement ΔX in the horizontal plane, displacement ΔY in the vertical plane) of the retina incident position with respect to the reference position on the retina, as in step S23.

(S35: Change incident angle)
Next, as in step S24, the main control unit 211 changes the incident angle condition in the ray tracing process so that the incident angle of the measurement light LS deflected by the optical scanner 88 on the cornea Cr changes by a predetermined small angle. do.

(S36: Identify the retina incidence position)
Next, similarly to step S25, the retinal incident position specifying unit 362C specifies a new retinal incident position by performing ray tracing processing on the measurement light LS whose incident angle has been changed in the cornea Cr in step S35. .

(S37: Calculate displacement ΔX', ΔY')
Similarly to step S26, the main control unit 211 determines the displacement of the retinal incident position relative to the reference position on the retina (displacement ΔX' in the horizontal plane, displacement ΔY' in the vertical plane) with respect to the retinal incident position identified in step S36. ) is calculated by the analysis unit 362.

(S38: Within threshold?)
Similarly to step S27, the main control unit 211 determines whether each of the displacements ΔX' and ΔY' calculated in step S37 is within a predetermined threshold value.

When it is determined in step S38 that each of the displacements ΔX' and ΔY' is within a predetermined threshold value (S38: Y), the operation of the ophthalmologic apparatus 1000 moves to step S39. When it is determined in step S38 that each of the displacements ΔX' and ΔY' is not within the predetermined threshold (S38: N), the operation of the ophthalmologic apparatus 1000 moves to step S35.

(S39: Generate control information for optical scanner)
When it is determined in step S38 that each of the displacements ΔX' and ΔY' is within the predetermined threshold (S38: Y), the main control unit 211 controls the incident measurement light LS when converged, as in step S28. The scan processing unit 362D generates control information for changing at least one of the scan width, scan speed, and scan center offset value of the optical scanner 88 so that the angle becomes the scan center angle. The main control unit 211 controls the optical scanner 88 based on the control information generated by the scan processing unit 362D.

This is the end of the process of step S14 according to the modification of the first operation example (end).

(Second operation example)
Next, a second operation example of the ophthalmologic apparatus 1000 according to the embodiment will be described. The second operation example differs from the first operation example mainly in that control information is provided to control the optical scanner 88 according to table information or a predetermined function without repeating the ray tracing process until the displacement converges. This is the point that generates .

In the second operation example as well, processing similar to the processing shown in FIGS. 10 and 11 is executed.

FIG. 15 shows a flowchart of the operation example of step S14 in FIG. 11 according to the second operation example. The storage unit 212 stores a computer program for implementing the processing shown in FIG. 15. The main control unit 211 executes the processing shown in FIG. 15 by operating according to this computer program.

(S41: Obtain eyeball model)
The main control unit 211 causes the retina incidence position specifying unit 362C to acquire an eyeball model (an eyeball model such as a known model eye) stored in advance in the storage unit 212, as in step S21.

(S42: Identify the retina incidence position)
Next, the main control unit 211 causes the retina incidence position identification unit 362C to specify the retina incidence position of the measurement light LS deflected by the optical scanner 88, as in step S22.

(S43: Calculate displacement ΔX, ΔY)
Next, the main control unit 211 causes the analysis unit 362 to calculate the displacement (displacement ΔX in the horizontal plane, displacement ΔY in the vertical plane) of the retina incident position with respect to the reference position on the retina, as in step S23. Although FIG. 16 shows the displacement ΔX in the horizontal plane due to the measurement light LS deflected around the pivot point Pv, which is an optically conjugate position with the optical scanner 88, the same applies to the displacement ΔY in the vertical plane. be. The reference position is, for example, a position corresponding to the fovea specified from the tomographic image of the eye E acquired by the OCT optical system 8. For example, by associating the position of each part in the tomographic image with the position of each part in the eyeball model in advance, it is possible to specify the position in the eyeball model that corresponds to the part specified in the tomographic image. Thereby, the analysis unit 362 can specify the displacement (displacement in the X-axis direction, displacement in the Y-axis direction) of the retina incidence position with respect to the reference position.

(S44: Identify the amount of change in the angle of incidence)
In this example, the storage unit 212 stores table information in advance. The amount of change in the angle of incidence of the measurement light LS (the amount of change in the deflection angle of the optical scanner 88) is associated with the table information in correspondence to the above-mentioned displacements ΔX and ΔY. Such table information is obtained in advance by calculation using the eyeball model described above. The main control unit 211 refers to the table information and causes the scan processing unit 362D to specify the amount of change in the angle of incidence of the measurement light LS corresponding to the displacements ΔX and ΔY calculated in step S43.

Note that in step S44, the amount of change in the angle of incidence is specified with reference to the table information, but the amount of change in the angle of incidence may be specified according to a predetermined function. The predetermined function is expressed, for example, by a first-order or second-order polynomial (or a third-order or higher-order polynomial) using displacements ΔX and ΔY as variables.

(S45: Generate control information for optical scanner)
The main control unit 211 controls at least one of the scan width, scan speed, and scan center offset value of the optical scanner 88 so that the predetermined position becomes the scan center based on the amount of change in the incident angle specified in step S44. The scan processing unit 362D generates control information for changing the one. For example, the main control unit 211 generates control information such that the incident angle that reflects the specified amount of change in the incident angle becomes the scan center angle. The main control unit 211 controls the optical scanner 88 based on the generated control information.

This completes the process of step S14 in FIG. 11 (end).

In this example, since it is executed every time an OCT scan is performed, the change in displacement of the retinal center position with respect to the reference position converges in stages.

In the process of FIG. 15, the retinal incident position is specified using the eyeball model stored in advance in the storage unit 212, but the process according to the embodiment is not limited to this. For example, the retinal incident position may be specified using an eyeball model that includes intraocular parameters representing the optical characteristics of the eye E to be examined.

FIG. 17 shows a flowchart of an operation example of step S14 according to a modification of the second operation example. The storage unit 212 stores a computer program for implementing the processing shown in FIG. 17. The main control unit 211 executes the processing shown in FIG. 17 by operating according to this computer program.

(S51: Obtain measurement value)
The main control unit 211 causes the eyeball model generation unit 361 to acquire the corneal shape parameter of the eye E to be examined, the eye refractive power of the eye E to be examined, and the axial length. The corneal shape parameters and the like are acquired by measuring the eye E to be examined, as described above. The corneal shape parameters are obtained by performing keratometry on the eye E to be examined. The eye refractive power is obtained by performing reflex measurement on the eye E to be examined. The axial length is obtained, for example, by performing OCT measurement on the eye E to be examined. Intraocular parameters other than the axial length may be acquired as the intraocular parameters.

(S52: Generate eyeball model)
Next, as in step S32, the main control unit 211 uses the corneal shape parameter acquired in step S31, the eye refractive power, and the axial length calculated by the parameter calculation unit 361A to determine the three-dimensional shape of the eye E to be examined. The model generation unit 361B generates an eyeball model.

(S53: Identify the retina incidence position)
Next, the main control unit 211 causes the retina incidence position identification unit 362C to specify the retina incidence position of the measurement light LS deflected by the optical scanner 88, as in step S42.

(S54: Calculate displacement ΔX and ΔY)
Next, the main control unit 211 causes the analysis unit 362 to calculate the displacement (displacement ΔX in the horizontal plane, displacement ΔY in the vertical plane) of the retina incident position with respect to the reference position on the retina, as in step S43.

(S55: Determine the amount of change in the angle of incidence)
Similarly to step S44, the main control section 211 refers to the table information and causes the scan processing section 362D to specify the amount of change in the angle of incidence of the measurement light LS corresponding to the displacements ΔX and ΔY calculated in step S53.

(S56: Generate control information for optical scanner)
Similar to step S45, the main control unit 211 controls the scan width, scan speed, and scan center of the optical scanner 88 so that the predetermined position becomes the scan center based on the amount of change in the angle of incidence specified in step S55. The scan processing unit 362D generates control information for changing at least one of the offset values. The main control unit 211 controls the optical scanner 88 based on the generated control information.

With this, the process of step S14 according to the modified example of the second operation example is completed (end).

[Action/Effect]
The functions and effects of the ophthalmological device according to the embodiment will be explained.

The ophthalmological apparatus (1000) according to some embodiments includes an optical system (OCT optical system 8), an acquisition section (anterior segment camera 300), an analysis section (362), a control section (210, a main control section). 211). The optical system includes an optical scanner (88), and irradiates the subject's eye (E) with light (measurement light LS) that is deflected by the optical scanner. The acquisition unit acquires an anterior segment image of the subject's eye. The analysis unit specifies a corneal incidence position on the cornea (Cr) of the eye to be examined, where the above-mentioned light is incident, by analyzing the anterior segment image acquired by the acquisition unit, and determines whether the light incident on the cornea incidence position is on the cornea (Cr) of the eye to be examined. Identify the retinal incident position of the incident light on the retina. The control unit controls the optical scanner based on the displacement of the retinal incident position with respect to the reference position (fovea) on the retina.

According to such a configuration, it is possible to specify the retinal incident position from the anterior segment image and control the optical scanner based on the displacement of the retinal incident position with respect to the reference position. Positioning can be performed so that light is incident on the This makes it possible to control tracking of the retina from the anterior segment image. In this case, there is no need to directly observe the retina, and it is possible to eliminate the need for a fundus illumination system that irradiates the fundus (retina) with illumination light.

Some embodiments include an alignment optical system (alignment light projection system 2) that projects an alignment light beam onto the subject's eye, and the analysis unit analyzes an image (Purkinje image) formed based on the alignment light beam in the anterior segment image. The corneal incident position is determined based on.

According to such a configuration, since the corneal incident position is specified based on the position of the Purkinje image in the anterior segment image, it becomes possible to specify the corneal incident position with high accuracy. As a result, it becomes possible to specify the retinal incident position with high accuracy, and it becomes possible to perform highly accurate positioning from the anterior segment image.

Some embodiments include a moving mechanism (200) that relatively moves the subject's eye and the optical system, and the control unit moves the moving mechanism based on the image formed based on the alignment light flux in the anterior segment image. After controlling , the optical scanner is controlled based on the above displacement.

According to such a configuration, after the alignment between the eye to be examined and the optical system is completed based on the image based on the alignment light beam, positioning based on the specified retina incidence position becomes possible. Thereby, highly accurate tracking control on the retina can be performed at an early stage.

In some embodiments, the acquisition unit includes two or more imaging units (anterior segment cameras 300) that image the anterior segment from different directions substantially simultaneously, and the control unit controls the positions of the two or more imaging units. and the position of the image obtained by analyzing two or more photographed images obtained by two or more photographing units.

According to such a configuration, alignment between the eye to be examined and the optical system can be performed over a wide dynamic range.

In some embodiments, the analysis unit identifies the retinal incident position by performing ray tracing processing on the light incident on the corneal incident position using ocular parameters representing optical characteristics of the eye to be examined or a predetermined model eye. do.

According to such a configuration, it becomes possible to specify the retinal incident position from the anterior eye segment image through simple processing.

In some embodiments, the control unit is configured such that the amount of change in the displacement of the retinal incident position with respect to the reference position on the retina is within a predetermined threshold value with respect to the predetermined amount of change in the angle of incidence of light at the corneal incident position. Control information is identified by repeating the ray tracing process, and the optical scanner is controlled based on the control information.

According to such a configuration, it becomes possible to control the optical scanner so as to scan a desired position by repeating the ray tracing process.

In some embodiments, the control unit specifies the amount of change in the angle of incidence of light at the corneal incident position using table information or a function corresponding to the optical characteristics of the eye to be examined or a predetermined model eye, and determines the amount of change in the angle of incidence of light at the corneal incident position. Identifying control information based on the amount and controlling the optical scanner based on the control information.

According to such a configuration, the optical scanner can be controlled so as to scan a desired position by using table information or a function, so that the process of aligning the anterior segment image to the desired position on the retina is performed. It becomes possible to simplify.

In some embodiments, the optical characteristics include corneal shape information of the eye to be examined.

According to such a configuration, it becomes possible to perform more accurate positioning (tracking) in consideration of the optical characteristics of the eye to be examined.

In some embodiments, the optical system includes a corneal topography measurement optical system (keratometry system 3) that projects a measurement pattern onto the eye to be examined and detects the return light, and the return light obtained by the corneal topography measurement optical system is It includes a corneal shape calculation unit (222) that calculates corneal shape information of the eye to be examined based on the light detection results.

According to such a configuration, it is possible to provide an ophthalmologic apparatus that has a simple configuration and can perform more accurate positioning (tracking) in consideration of the optical characteristics of the eye to be examined.

In some embodiments, the optical property includes a refractive power value (ocular refractive power) of the eye to be examined.

According to such a configuration, it becomes possible to perform more accurate positioning (tracking) in consideration of the optical characteristics of the eye to be examined.

In some embodiments, the optical system includes a refractive power measurement optical system (a reflex measurement projection system 6, a reflex measurement light receiving system 7) that projects light onto the subject's eye and detects the returned light, It includes a refractive power value calculation unit (eye refractive power calculation unit 221) that calculates the refractive power value of the eye to be examined based on the detection result of the return light obtained by the system.

According to such a configuration, it is possible to provide an ophthalmologic apparatus that has a simple configuration and can perform more accurate positioning (tracking) in consideration of the optical characteristics of the eye to be examined.

In some embodiments, the optical property includes intraocular distance of the subject's eye.

According to such a configuration, it becomes possible to perform more accurate positioning (tracking) in consideration of the optical characteristics of the eye to be examined.

In some embodiments, the optical system splits the light (L0) from the light source (OCT light source 101) into a reference light (LR) and a measurement light (LS), and receives the measurement light deflected by the optical scanner. It includes an OCT optical system (8) that projects onto the eye and detects interference light (LC) between the return light from the eye to be examined and the reference light, and detects the interference light (LC) from the eye to be examined based on the detection result of the interference light obtained by the OCT optical system. It includes an intraocular distance calculation unit (parameter calculation unit 361A) that calculates the intraocular distance.

According to such a configuration, it is possible to provide an ophthalmologic apparatus that has a simple configuration and can perform more accurate positioning (tracking) in consideration of the optical characteristics of the eye to be examined.

In some embodiments, the analysis unit identifies the reference position based on the detection result of interference light obtained by the OCT optical system.

According to such a configuration, it becomes possible to specify the retinal incident position with respect to the reference position with high accuracy in accordance with the eye to be examined.

In some embodiments, the optical system splits the light (L0) from the light source (OCT light source 101) into a reference light (LR) and a measurement light (LS), and receives the measurement light deflected by the optical scanner. It includes an OCT optical system (8) that is projected onto the eye and detects the interference light (LC) between the return light from the eye to be examined and the reference light, and the analysis section uses the detection results of the interference light obtained by the OCT optical system. The reference position is determined based on the

According to such a configuration, it becomes possible to specify the retinal incident position with respect to the reference position with high accuracy in accordance with the eye to be examined.

<Others>
In the above embodiment, a case has been described in which the eye refractive power is obtained by projecting light onto the subject's eye, but the configuration of the ophthalmological apparatus according to the embodiment is not limited to this. The ophthalmological apparatus according to the embodiment may obtain the eye refractive power based on wavefront aberration obtained using a known wavefront sensor.

The tracking process according to the above embodiment can be applied to the alignment process between the apparatus optical system and the eye to be examined.

The embodiment shown above or its modification example is only an example for implementing the present invention. Those who wish to implement this invention can make arbitrary modifications, omissions, additions, etc. within the scope of the gist of this invention.

2 Alignment light projection system 3 Kerato measurement system 4 Fixation projection system 5 Anterior segment observation system 6 Reflex measurement projection system 7 Reflex measurement light receiving system 8 OCT optical system 9 Processing section 210 Control section 211 Main control section 212 Storage section 212A Intraocular Parameters 220 Arithmetic processing section 221 Eye refractive power calculation section 222 Corneal shape calculation section 224 Image forming section 225 Data processing section 300 Anterior segment camera 350 Alignment processing section 360 Tracking processing section 361 Eyeball model generation section 362 Analysis section 1000 Ophthalmology apparatus Cr Cornea E Eye to be examined Ef Fundus

Claims (12)

an optical system that includes an optical scanner and irradiates the eye to be examined with light deflected by the optical scanner;
an alignment optical system that projects an alignment light beam onto the eye to be examined;
an acquisition unit that acquires an anterior segment image of the eye to be examined;
Identifying a corneal incidence position where the light is incident on the cornea of the eye to be examined based on an image formed based on the alignment light flux in the anterior ocular segment image acquired by the acquisition unit, and making the light incident on the cornea incidence position. The light incident on the corneal incident position is incident on the retina of the eye to be examined by performing ray tracing processing on the light using eyeball parameters representing the optical characteristics of the eye to be examined or a predetermined model eye. An analysis section that identifies the location,
a moving mechanism that relatively moves the eye to be examined and the optical system;
After controlling the moving mechanism based on an image formed based on the alignment light beam in the anterior segment image, controlling the optical scanner based on a displacement of the retinal incident position with respect to a reference position on the retina . a control unit that performs tracking control ;
ophthalmological equipment including; The acquisition unit includes two or more imaging units that image the anterior segment from different directions substantially simultaneously,
The control unit controls the movement mechanism based on the positions of the two or more imaging units and the position of the image obtained by analyzing two or more captured images acquired by the two or more imaging units. The ophthalmologic apparatus according to claim 1, wherein the ophthalmologic apparatus controls the ophthalmologic apparatus. The control unit performs ray tracing so that, with respect to a predetermined amount of change in the angle of incidence of the light at the corneal incident position, an amount of change in displacement of the retinal incident position with respect to a reference position on the retina is within a predetermined threshold value. The ophthalmologic apparatus according to claim 1 or 2, wherein control information is specified by repeating processing, and the optical scanner is controlled based on the control information. The control unit specifies the amount of change in the angle of incidence of the light at the corneal incident position using table information or a function corresponding to the optical characteristics of the eye to be examined or a predetermined model eye, and based on the specified amount of change. The ophthalmologic apparatus according to any one of claims 1 to 3, wherein control information is specified using the control information, and the optical scanner is controlled based on the control information. The ophthalmologic apparatus according to any one of claims 1 to 4, wherein the optical characteristics include corneal shape information of the eye to be examined. The optical system includes a corneal shape measurement optical system that projects a measurement pattern onto the eye to be examined and detects the returned light,
The ophthalmological apparatus according to claim 5 , further comprising a corneal shape calculation unit that calculates the corneal shape information of the eye to be examined based on the detection result of the return light obtained by the corneal shape measurement optical system. The ophthalmologic apparatus according to any one of claims 1 to 6, wherein the optical characteristics include a refractive power value of the eye to be examined. The optical system includes a refractive power measurement optical system that projects light onto the eye to be examined and detects the returned light,
The ophthalmologic apparatus according to claim 7 , further comprising a refractive power value calculation unit that calculates a refractive power value of the eye to be examined based on a detection result of the returned light obtained by the refractive power measuring optical system. The ophthalmologic apparatus according to any one of claims 1 to 8, wherein the optical characteristics include an intraocular distance of the eye to be examined. The optical system splits light from a light source into reference light and measurement light, projects the measurement light deflected by the optical scanner onto the subject's eye, and combines the return light from the subject's eye with the reference light. includes an OCT optical system that detects the interference light of
The ophthalmologic apparatus according to claim 9 , further comprising an intraocular distance calculation unit that calculates an intraocular distance of the eye to be examined based on a detection result of the interference light obtained by the OCT optical system. The ophthalmologic apparatus according to claim 10 , wherein the analysis unit specifies the reference position based on a detection result of the interference light obtained by the OCT optical system. The optical system splits light from a light source into a reference light and a measurement light, projects the measurement light deflected by the optical scanner onto the eye to be examined, and combines the return light from the eye to be examined and the reference light. includes an OCT optical system that detects the interference light of
The ophthalmologic apparatus according to any one of claims 1 to 11 , wherein the analysis unit specifies the reference position based on a detection result of the interference light obtained by the OCT optical system. .

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