JPH04317624A - Ophthalmic apparatus - Google Patents

Abstract

PURPOSE:To reduce the manufacturing cost. CONSTITUTION:In the ophthalmic apparatus for irradiating an eye with light, catching a reflected light and examining a state of the eye, an incident part 26 which is provided with one or more LEDs 21, has light transmissivity, and on which light from one or more LEDs 21 is made incident, and a light guide 25 which is formed annularly, and has an emitting part 77 for emitting an incident light are provided.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ophthalmological device that shines light onto the eye and captures the reflected light to examine the condition of the eye.

0002

2. Description of the Related Art As is well known, in an ophthalmological apparatus, an image of some kind is projected onto the eye, and the reflected image is measured or observed optically or electrically. For example, as a means to observe the shape of the cornea or measure corneal curvature, a ring image is projected onto the corneal surface, and the ring image reflected on the corneal surface is measured optically and electrically. Is going.

[0003]This type of ophthalmological apparatus has conventionally been used, for example, as shown in FIG.
0, a ring-shaped fluorescent lamp 50, a ring-shaped strobe tube, or the like is used as a light source. Generally, this ring-shaped fluorescent lamp etc. needs to correspond to the size of the cornea to some extent, so the outer diameter is 60 mm and the tube diameter is 10 mm.
A diameter of about mm is used.

0004

[Problem to be Solved by the Invention] However, with such conventional technology, the dimensions of ring-shaped fluorescent lamps, etc. are different from those commonly used, and are small and special, so it is extremely difficult to use. There is a problem in that an expensive light source must be used, which increases manufacturing costs.

[0005]The present invention has been made in view of these conventional problems, and an object of the present invention is to provide an ophthalmologic apparatus that can reduce manufacturing costs.

[0006]

[Means for Solving the Problems] An ophthalmological device for achieving the above object is provided with one or more light sources, has light transmittance,
The present invention is characterized in that it is provided with a light guide having an entrance part into which light from one or more of the light sources enters, and an exit part formed in a desired pattern shape and which outputs the incident light.

[0007] Here, the light guide is provided with a reflective material on at least a part of its outer peripheral surface other than the entrance part and the exit part to reflect the light that has passed through the inside inward. It is preferable that Moreover, it is preferable to use an LED as the light source.

[0008]

[Operation] The light from the light source is transmitted from the incident part of the light guide.
The light enters the light guide, is repeatedly reflected and refracted within the light guide, and is emitted from the emission section to the subject's eyes. At this time, if the shape of the injection part is, for example, annular, a continuous ring-shaped projection image can be obtained. Moreover, if the shape of the injection part is made into a double annular shape, a double ring-shaped projected image can be obtained. In this way, by changing the shape of the light guide's exit portion, projection images of various patterns can be easily obtained.

Furthermore, such a light guide can be manufactured at a much lower cost than manufacturing a hollow fluorescent tube with special dimensions, so that the manufacturing cost of the device can be reduced.

[0010] Furthermore, since an LED can be used as a light source, in such a case, it is better to use an LED than a fluorescent tube.
Since the lifespan is longer, the frequency of replacing the light source can be reduced, and the effort required for replacing the light source can be reduced.

[0011]

Embodiments Various embodiments of the ophthalmologic apparatus according to the present invention will be described below with reference to FIGS. 1 to 19. In addition, in explaining various embodiments, the same parts are given the same reference numerals and redundant explanations will be omitted.

A first embodiment of the ophthalmological apparatus will be described with reference to FIGS. 1 and 2. As shown in FIG. 1, the ophthalmological apparatus of this embodiment includes an apparatus main body 10 in which various optical systems and the like are built-in, a sliding table 11 that supports the apparatus main body 10, and a support stand that supports the face of the subject. 13, and a base 16 on which these are placed.

The apparatus main body 10 has a light emitter 20 that irradiates light to the eye E of the subject, and a light receiver 30 that receives the light reflected from the eye E. As shown in FIG. 2, the light emitter 20 includes four LEDs 21, 21, . . . that serve as light sources, and
A light guide 25 is provided that guides the light from the LED 21 to the eye E of the subject. The LED 21 has relatively high light diffusivity. The light guide 25 is made of a polycarbonate resin having light transparency. The light guide 25 is formed with an entrance part 26 into which light from the LEDs 21, 21, . Both the entrance section 26 and the exit section 27 have an annular shape.
The outer diameter of the injection part 27 is larger than that of the injection part 27. In other words, the light guide 25
It has a cylindrical shape with the injection portion 27 as the end and the diameter decreasing toward the injection portion 27 side.

The cylindrical light guide 25 is provided so that its central axis substantially coincides with the optical axis of the eye E. Further, as shown in FIG. 2, when considering the cut surface of the light guide 25, the straight body part between the entrance part 26 and the exit part 27 is such that the light flux of the reflected image from the eye E is directed toward the optical axis of the eye E. It is tilted at an angle θ with respect to the optical axis of the eye E so that it is parallel to the optical axis of the eye E. This is because measurement of reflected images is often performed in the optical axis direction of the eye E, so it is structurally convenient for the light emission direction to avoid the optical axis direction of the eye E. Note that the angle θ is preferably about 23°, but if the internal structure is flexible, it can be reduced to 0°.
But it doesn't matter.

The light receiver 30 is provided with various optical systems 31 having light receiving elements for receiving light reflected from the eye. The light receiver 30 is provided so that the optical axis of its optical system 31 coincides with the optical axis of the eye E.

The slide table 11 is slidably provided on the base 16 so that the distance from the support table 13 can be changed. The sliding operation of the slide 11 is performed using a joystick 12 provided on the slide 11. The support stand 13 is provided at the end of the base 16, and has a chin rest part 14 for receiving the chin of the subject and a forehead rest part 15 against which the forehead of the subject comes into contact.

The operation of the ophthalmologic apparatus of this embodiment will be explained. The light emitted from the LEDs 21, 21, . . . enters the light guide 25 through the entrance portion 26 thereof. This light is repeatedly reflected and refracted along the wall surface of the light guide 25, and is emitted from the emission part 27 to the eye E at an angle of θ with respect to the optical axis of the eye E.
eject in the direction of. The emitted light uses the LED 21 with relatively high light diffusivity as a light source, so four LEDs are used as the light source.
The light from D21, 21,... is diffused within the light guide,
It has a continuous ring shape corresponding to the shape of the injection part 27 and has uniform brightness.

The light emitted from the light guide 25 is directed to the eye E.
The light is reflected from the corneal surface and enters the light receiver 30. The examiner determines the condition of the cornea by observing the distortion of the ring-shaped reflected image obtained through the light receiver 30.

As described above, according to this embodiment, as a light emitter,
Since the LED 21, which is easily available, and the light guide 25, which has a solid structure and is relatively easy to manufacture, are used, manufacturing costs can be reduced. Further, when a ring-shaped fluorescent lamp 50 or a ring-shaped strobe tube as shown in FIG. 20 is used as a light source, electrodes 51, 5
However, in this example, since it is possible to obtain a ring image without any breaks, the cornea can be easily aligned evenly in each direction. It can be measured under the following conditions. Furthermore, since the LED 21, which has a longer lifespan than a ring-shaped fluorescent lamp or a ring-shaped strobe tube, is used as a light source, the frequency of replacing the light source can be reduced, and the effort required for replacing the light source can be reduced.

In this embodiment, the light guide 25 is made of polycarbonate resin, but it may be made of acrylic resin, glass, etc. as long as it is transparent to light. In addition, in this embodiment, LED2 serving as a light source
Although the number of 1 is set to four, this should be determined in consideration of the light diffusivity of the LED, the uniformity of the light intensity of the ring image, etc., and the number may be smaller or larger than four.

Next, the second, third, etc. embodiments of the ophthalmological apparatus will be described. In the following embodiments, only the structure of the light emitting device is different from the first embodiment. I will only explain about.

A second embodiment of the ophthalmological apparatus will be described with reference to FIG. The light emitter of this embodiment uses a trumpet-shaped light guide 25a. Light guide 25a
The shape of the exit part 27 is the same as that of the first embodiment, but the middle trunk part is bent so that the space from there to the entrance part 26 is expanded in the direction perpendicular to the optical axis of the eye E. I am using what I have. The bending angle of the middle body portion may be any angle as long as it does not exceed the critical angle for reflection of incident light, that is, the angle does not allow incident light to exit the light guide 25a.

In this way, the trumpet-shaped light guide 25
By using a, the dimension of the eye E in the optical axis direction can be shortened.

Next, a third embodiment of the ophthalmologic apparatus will be described using FIGS. 4 and 5. In this embodiment, like the second embodiment, the middle body portion of the light guide 25b is bent. The light guide 25b is bent in a direction perpendicular to the optical axis of the eye E at a predetermined distance from the emission part 26 to the entrance part 27 side so as to follow the outer shape of the light receiver 30, and then a predetermined distance from the bent point. Here, it is bent in a direction parallel to the optical axis of the eye E.

In this way, since the light guide 25b is formed to match the outer shape of the light receiver 30, wasted space can be reduced and the device can be made more compact. Note that the light guide does not need to be bent as in this embodiment, but may be bent to match the outer shape of the light receiver 30, and the direction in which it is bent and the number of times it is bent are basically free.

Next, the fourth embodiment of the ophthalmologic apparatus will be explained using FIGS. 6 and 7, the fifth embodiment of the ophthalmologic apparatus will be explained using FIGS. 8 and 9, and FIGS. A sixth example will be described.

These embodiments differ from the first embodiment in the shape of the injection section. The light guide 25c of the fourth embodiment is branched at its middle body and has two concentric emitting portions 27c, 27c.

Similar to the fourth embodiment, the light guide 25d of the fifth embodiment is branched at the middle part and has two injection parts 27d, 27d, but the light guide 25d has a rectangular shape. It is something that accomplishes the following.

The light guide 25e of the sixth embodiment is branched into a plurality of parts at the middle body part, and the ejection part 27e has a grid-like shape.

As described above, according to the present invention, projection images of various patterns can be easily obtained by changing the shape of the exit portion of the light guide. Note that in the fourth example, the fifth example, and the sixth example, the LED 21
The quantity of LE is four in each case, but when the total area of the injection part is relatively large as in these examples, the number of LE
It would be good to further increase the quantity of D21.

Next, a seventh embodiment of the ophthalmologic apparatus will be explained using FIGS. 12 and 13. In the light guide 25f of this embodiment, the incident part 26f is divided into a plurality of parts corresponding to the plurality of LEDs 21, 21, . A reflecting mirror 28 is attached to the side surface of the middle trunk on the side of the incident section 26f.

By attaching the reflective mirror 28 to the outer circumferential surface of the light guide 25f in this way, the reflection rate is improved and the light from the LED 21 can be emitted effectively.

Note that in this embodiment, the light guide 2
In order to improve the reflection rate on the outer circumferential surface of 5f, a reflective mirror 28 is attached, but chromium vapor deposition or the like may be applied. In addition, in this embodiment, such a reflective material was applied only to the side surface of the middle body on the side of the entrance part 26f, but in order to more effectively emit the light from the LED 21, the outer periphery other than the entrance part 26f and the exit part 27 was applied. A reflective material may be applied to the entire surface. Further, the reflective material may be applied not only to the light guide having the shape shown in this embodiment, but also to the light guides shown in various other embodiments.

Next, an eighth embodiment of the ophthalmologic apparatus will be described with reference to FIGS. 14 and 15. As shown in FIG. 14, the light guide 25g of this embodiment has an incident part 26
The shape of the middle body part on the g side is formed to form a rectangular shape when viewed from a direction parallel to the optical axis of the eye E, and this end face is formed as the entrance part 2.
The weight was 6g. Note that in this embodiment, LED2
There are six 1's. Also in this example, the seventh
Similar to the embodiment described above, a reflecting mirror 28 is provided on the side surface of the middle body on the side of the incident section 26g.

Next, a ninth embodiment of the ophthalmologic apparatus will be described using FIGS. 16 and 17. The light emitting device of this embodiment is basically the same as that of the second embodiment, but the LED 21 serving as the light source is provided with the LED 21 tilted so that its main light emitting direction does not face the optical axis of the eye. therefore,
The basic shape of the light guide 25h is also the same as that of the second embodiment, but in order to effectively guide the light from the LED 21 into the light guide 25h, an L
A recess into which the ED 21 can be inserted is formed, and the entrance part 26 is inserted into the recess.
h. As shown in FIG. 16, the LED 21 is inserted into the above-mentioned recess so that its main light emitting direction is oriented at an angle α with respect to the optical axis of the eye.

In this manner, by providing the LED 21 at an angle, the width of the luminous flux outputted from the LED 21 becomes wider when viewed from the emission part 27 side, and the apparent light diffusivity of the LED 21 is improved. The brightness of the projected image can be made more uniform.

Next, a tenth embodiment of the ophthalmologic apparatus will be described using FIGS. 18 and 19.

In this embodiment, a linear fluorescent lamp 22 is used as a light source. The light guide 25i has a cylindrical shape, one end surface of which is perpendicular to the optical axis of the eye, and the other end surface of which is formed at approximately 45 degrees to the optical axis of the eye. . A recess into which the fluorescent lamp 22 can be attached is formed in parallel to the axial direction of the light guide 25i on the outer peripheral surface side of the light guide 25i. The fluorescent lamp 22 is mounted in this recess.

[0039] This recessed part forms an entrance part 26i, from which light from the fluorescent lamp 22 enters into the light guide 25i. The incident light passes through the cylindrical light guide 25i and exits from the exit portion 27, which is one end surface described above.

Although only one fluorescent lamp 22 is used in this embodiment, the number may be increased depending on the degree of uneven illumination. Furthermore, although this example shows an example of a light source used as a light source, as mentioned above, it is preferable to use an LED as a light source because it generally has a longer lifespan than a fluorescent lamp. .

[0041]

According to the present invention, it is not necessary to use a small and specially sized fluorescent lamp in order to obtain a projected image of a target pattern, so that manufacturing costs can be reduced.

Furthermore, by changing the shape of the light guide's exit portion, projection images of various patterns, such as a continuous ring-shaped projection image or a double-ring-shaped projection image, can be easily obtained.

[Brief explanation of drawings]

FIG. 1 is an overall side view conceptually showing an ophthalmologic apparatus according to a first embodiment of the present invention.

FIG. 2 is a sectional view of a light emitter according to the first embodiment.

FIG. 3 is a sectional view of a light emitter according to a second embodiment of the present invention.

FIG. 4 is a rear view of a light emitting device according to a third embodiment of the present invention.

5 is a sectional view taken along the line V-V in FIG. 4. FIG.

FIG. 6 is a front view of a light emitter according to a fourth embodiment of the present invention.

7 is a sectional view taken along the line VII-VII in FIG. 6. FIG.

FIG. 8 is a front view of a light emitter according to a fifth embodiment of the present invention.

9 is a sectional view taken along the line IX-IX in FIG. 8. FIG.

FIG. 10 is a front view of a light emitter according to a sixth embodiment of the present invention.

11 is a sectional view taken along the line XI-XI in FIG. 10. FIG.

FIG. 12 is a front view of a light emitter according to a seventh embodiment of the present invention.

13 is a sectional view taken along the line XIII-XIII in FIG. 12. FIG.

FIG. 14 is a front view of a light emitter according to an eighth embodiment of the present invention.

15 is a sectional view taken along the line XV-XV in FIG. 14. FIG.

FIG. 16 is a front view of a light emitter according to a ninth embodiment of the present invention.

17 is a sectional view taken along the line XVII-XVII in FIG. 16. FIG.

FIG. 18 is a front view of a light emitter according to a tenth embodiment of the present invention.

19 is a sectional view taken along the line XIX-XIX in FIG. 18. FIG.

FIG. 20 is a front view of a light source used in a conventional ophthalmological device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10... Apparatus main body, 11... Slide table, 13... Support stand, 16...
Base, 20... Light emitter, 21... LED, 22... Fluorescent lamp,
25, 25a, 25b, 25c, 25d, 25e, 25
f, 25g, 25h, 25i...Light guide, 26,2
6f, 26g, 26h, 26i...Incidence part, 27, 27c
, 27d, 27e...Ejection section, 28...Reflection mirror, 30...
Receiver.

Claims (4)

[Claims] Claim 1: An ophthalmological device for inspecting the condition of the eye by shining light on the eye and capturing the reflected light, comprising one or more light sources, having light transmittance, and transmitting light from one or more of the light sources. 1. An ophthalmological device comprising: a light guide having an entrance section into which light enters, and an exit section formed in a desired pattern shape and from which the incident light exits. 2. The ophthalmological device according to claim 1, wherein the ejection portion has an annular shape. 3. At least a part of the outer circumferential surface of the light guide other than the entrance part and the exit part is provided with a reflective material that reflects the light that has passed through the inside inward. The ophthalmological device according to claim 1 or 2, characterized in that: 4. The light guide includes a light guide in which the emitting portion has an annular shape, and a light receiver that captures light reflected from the eye, wherein the light guide has a central axis of the annular emitting portion. The ophthalmological equipment according to claim 1, 2 or 3, wherein the ophthalmological device is provided so as to substantially coincide with the optical axis of the light receiver.