JP2011089895A - Device and method of hyperspectral imaging - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hyperspectral imaging device achieving photographing of a moving image by increasing the number of photographed images of hyperspectral image data per unit time, and a hyperspectral imaging method. <P>SOLUTION: The hyperspectral imaging device includes: a variable slit member 104 constituting a slit 104A for forming light from an object into linear light parallel to a first direction, allowing the light to pass therethrough, and moving the position of the slit from one end side to the other end side in a second direction within the member; a spectral optical element 106 for dividing light having passed through the slit into a plurality of wavelength regions defined by hyperspectra; an imaging element 110 for receiving light of each wavelength region divided by the spectral optical element; and an image generating part 112 for calculating the intensity of light for each wavelength region based on an electric signal and generating a single two-dimensional image for each wavelength region based on the relationship between the position of the slit and the position of the light of each wavelength region received by the imaging element at the imaging element when the slit is moved from the one end side to the other end side once. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a hyperspectral imaging apparatus and a hyperspectral imaging method.

  A hyperspectral camera is an imaging device that obtains an image for each wavelength region by splitting light from a subject into a plurality of wavelength regions defined by the hyperspectrum. Hyperspectral sensors have been used in agricultural fields, environmental fields, etc., mounted on satellites and aircraft. In the future, it is expected to be used in the medical field and food field.

  According to the hyperspectral technology, the conventional color concept can be extended to the spectral region, and phenomena that are invisible to the human eye can be visualized. Patent Document 1 discloses a technique in which hyperspectral technology is applied to an endoscope system.

JP 2009-39280 A

  The technical field in which an image acquired by the hyperspectral camera can be used is not limited to the above-described field. For example, moving objects or objects whose shapes change over time can be photographed as subjects, and measurement of these objects using hyperspectral technology may enable unprecedented object recognition and characteristic analysis. is there.

  By the way, the conventional hyperspectral camera can acquire an image represented in a two-dimensional space for each wavelength region, but can only acquire a still image. For example, in the conventional hyperspectral camera, it takes ten to several tens of seconds or several minutes to acquire a set of spectral image data. Therefore, in order to recognize and analyze a moving object or an object whose shape changes with time, it is required to acquire an image (moving image) in the time axis direction. It was difficult to obtain moving images with real-time characteristics.

  Therefore, the present invention has been made in view of the above problems, and an object of the present invention is to increase the number of hyperspectral image data captured per unit time, and to move a moving image of hyperspectral image data. It is an object of the present invention to provide a novel and improved hyperspectral imaging apparatus and hyperspectral imaging method capable of realizing imaging.

  In order to solve the above-described problem, according to one aspect of the present invention, a slit is formed that transmits light from a subject as linear light parallel to the first direction, and is perpendicular to the first direction. A variable slit member that moves the position of the slit within the member from one end side to the other end side in the second direction, and a spectroscopic optical element that splits light transmitted through the slit into a plurality of wavelength regions defined by a hyperspectrum, An image sensor having a plurality of pixels that receive light for each wavelength region spectrally separated by the spectroscopic optical element and photoelectrically convert it to generate an electrical signal, and calculates the intensity of light for each wavelength region based on the electrical signal. Based on the relationship between the position of the slit in the variable slit member and the position of the light for each wavelength region received by the image sensor in the image sensor, when the slit moves once from the one end side to the other end side, 2D image Hyperspectral imaging apparatus characterized by comprising an image generator for generating for each wavelength region is provided.

  The variable slit member may form a slit by electrically transmitting and blocking light by liquid crystal in response to voltage application, and may electrically move the position of the slit.

  You may further provide the optical amplification part which amplifies the intensity | strength of the light for every wavelength range spectrally divided by the said spectroscopic optical element, and irradiates an image pick-up element with the amplified light.

A light-emitting diode that emits light toward the variable slit member, the spectroscopic optical element, and the imaging element; a band-pass filter that passes the peak wavelength of the light emitted by the light-emitting diode;
A wavelength calibration light source having the following may be further provided.

  You may further provide the diffusion plate which diffuses and permeate | transmits the light which passed the band pass filter of the said wavelength calibration light source.

  In order to solve the above problem, according to another aspect of the present invention, the variable slit member forms a slit that transmits light from the subject as linear light parallel to the first direction, and transmits the slit. The step of moving the position of the slit within the member from one end side to the other end side in the second direction perpendicular to the first direction, and the spectroscopic optical element is defined by hyperspectral light transmitted through the slit A step of splitting the light into a plurality of wavelength regions, a step of having an image sensor having a plurality of pixels that receive light for each wavelength region dispersed by the spectroscopic optical element and photoelectrically convert the light to generate an electrical signal, and an image generation unit However, based on the electrical signal, calculate the intensity of light for each wavelength region, based on the relationship between the position of the slit in the variable slit member and the position of the light for each wavelength region received by the image sensor in the image sensor, Pickpocket When bets are moved once from one end to the other end, hyperspectral imaging method characterized by comprising the steps of generating a single two-dimensional image for each wavelength region is provided.

  According to the present invention, the number of captured hyperspectral image data per unit time can be increased, and moving image capturing of hyperspectral image data can be realized.

It is explanatory drawing which shows the structure and operation | movement of the hyperspectral camera 100 which concern on one Embodiment of this invention. 2 is a block diagram illustrating a configuration of a hyperspectral camera 100 according to the embodiment. FIG. It is explanatory drawing which shows the optical system of the hyperspectral camera 100 concerning the embodiment. It is explanatory drawing which shows the electronic slit 104 which concerns on the same embodiment. It is explanatory drawing which shows the image intensifier 108 which concerns on the embodiment. It is explanatory drawing which shows the wavelength calibration part 116 which concerns on the same embodiment. It is explanatory drawing which shows the wavelength calibration light source 170 which concerns on the same embodiment. 8A is a graph showing the relationship between the emission intensity of the LED 174 and the wavelength, FIG. 8B is a graph showing the relationship between the transmittance of the BPF 176 and the wavelength, and FIG. 8C is a graph showing the relationship between the LED 174 and FIG. It is a graph which shows the relationship between the emitted light intensity of this, and a wavelength. It is a flowchart which shows operation | movement of the hyperspectral camera 100 which concerns on the same embodiment. It is explanatory drawing which shows the definition of hyperspectral data. It is explanatory drawing which shows the definition of hyperspectral data. It is a block diagram which shows the conventional hyperspectral camera.

  Exemplary embodiments of the present invention will be described below in detail with reference to the accompanying drawings. In addition, in this specification and drawing, about the component which has the substantially same function structure, duplication description is abbreviate | omitted by attaching | subjecting the same code | symbol.

[1. Configuration of Embodiment]
First, the configuration of the hyperspectral camera 100 according to an embodiment of the present invention will be described. FIG. 1 is an explanatory diagram showing the configuration and operation of a hyperspectral camera 100 according to the present embodiment. FIG. 2 is a block diagram illustrating a configuration of the hyperspectral camera 100 according to the present embodiment. FIG. 3 is an explanatory diagram showing an optical system of the hyperspectral camera 100 according to the present embodiment.

  The hyperspectral camera 100 according to the present embodiment is an example of a hyperspectral imaging apparatus, and is an imaging apparatus that can acquire images for a plurality of wavelength regions defined by the hyperspectrum as moving images.

  The hyperspectral camera 100 can transmit image data to an information processing apparatus such as a PC (personal computer) 140, a video monitor 150, and the like. The captured image is processed by the PC 140, and the video monitor 150 is connected via the video output conversion circuit 152. Can be displayed. The hyperspectral camera 100, the PC 140, the video monitor 150, and the like are connected according to the Camera Link standard or the like, and data is transmitted / received via the I / F circuit 130.

  The hyperspectral camera 100 includes, for example, a light receiving lens 102, a lens 103, an electronic slit 104, an electronic slit driving circuit 105, a diffraction grating 106, an image intensifier 108, a control circuit 109, and a CMOS image sensor 110. , FPGA 112, RAM 114, wavelength calibration unit 116, sensitivity calibration light source 118, CPU 120, I / F circuit 130, illuminance sensor 160, and the like.

  The light receiving lens 102 receives light from the subject and irradiates the electronic slit 104 with the incident light. The light receiving lens 102 is driven by, for example, a focus driving unit, and can focus the subject image on the sensor main body 113 of the CMOS image sensor 110. The light receiving lens 102 may be replaced with a Fresnel lens.

  The electronic slit 104 is made of, for example, a transmissive monochrome liquid crystal, and the direction of the liquid crystal changes according to the applied voltage to form a slit 104A as shown in FIG. FIG. 4 is an explanatory diagram showing the electronic slit 104 according to the present embodiment. The electronic slit 104 can transmit light from the subject that has passed through the light receiving lens 102 at a portion where the slit 104A is formed. On the other hand, the electronic slit 104 blocks light from the subject in the light shielding portion 104B other than the portion where the slit 104A is formed. The slit 104A formed in the electronic slit 104 is an opening having a fine width.

  The slit 104A is, for example, an opening parallel to the X-axis direction (first direction) when the plane of the electronic slit 104 is represented by XY coordinates, and converts light from the subject into linear light parallel to the X-axis direction. Squeeze and transmit. Then, as shown in FIG. 4B, the slit 104A moves in the Y-axis direction (second direction) perpendicular to the X-axis direction from one end side to the other end side. The movement of the slit 104A is electrically controlled by a change in the direction of the liquid crystal.

  An example of the operation of the electronic slit 104 will be described. First, a voltage is applied to the liquid crystal at the time of activation to invert all pixels of the electronic slit 104 to black. Thereafter, the slit 104A is formed by making the pixels of an arbitrary line transparent. Then, after the image is acquired, the portion where the slit 104A has been formed is inverted to black, and the pixels on the line one pixel above become transparent. In this way, the subject (target object) is scanned by changing the position of the slit 104A. The electrical scanning method according to the present embodiment can be speeded up as compared with the conventional mechanical scanning method with a limited speed. In addition, there is an advantage that it is hardly affected by the environment in which vibration occurs.

  The light transmitted through the electronic slit 104 is irradiated to the diffraction grating 106. The electronic slit 104 is made of, for example, a ferroelectric liquid crystal. As a result, high-speed scanning of the subject can be realized by switching the slit position at high speed. Further, the number of sets of hyperspectral data (HSD) that can be acquired per unit time increases as the response speed of the electronic slit 104 increases, and the captured target object can be reproduced with smoother motion. Note that hyperspectral data (HSD) is a three-dimensional data set in which each pixel of a two-dimensional image has spectral spectrum intensity information.

  The electronic slit 104 is an example of a variable slit member. In the present invention, the variable slit member is not limited to the electronic slit 104. The variable slit member may have a configuration in which the slit is moved in a one-dimensional direction by a magnetic force, for example, by driving by a voice coil. Further, the movement of the slit of the variable slit member may be driven by an ultrasonic linear actuator or a micro linear motor, or may be configured by using a rotating mirror.

  The electronic slit driving circuit 105 outputs a driving signal to the electronic slit 104 to drive the electronic slit 104.

  The diffraction grating 106 is, for example, a substrate on which a large number of grooves are formed in parallel at equal intervals, and the linear light parallel to the X-axis direction that has passed through the electronic slit 104 is split into a plurality of wavelength regions. In the present embodiment, for example, a region from visible light of 400 to 800 nm to the near infrared is used as an application range, and the diffraction grating 106 separates the region into a plurality of bands (wavelength regions). The diffraction grating 106 is an example of a spectroscopic optical element. As the diffraction grating 106, for example, a transmission diffraction grating can be used. The diffraction grating may be a reflective diffraction grating such as a mechanical engraved diffraction grating or a holographic diffraction grating. In the present embodiment, the spectroscopic optical element is the diffraction grating 106, but the present invention is not limited to this example. The spectroscopic optical element may be, for example, a prism or a photoacoustic element (AOM: Acousto-Optic Modulator) that can spectrally decompose incident light.

  The relay lens 107 is an optical system member composed of a plurality of lenses, and the light split by the diffraction grating 106 is incident thereon. The relay lens 107 is provided, for example, before and after the image intensifier 108. The relay lens 107 irradiates the dispersed light to the sensor main body 113 of the CMOS image sensor 110 and forms an image of the dispersed light from the subject on the imaging surface of the sensor main body 113. Note that the relay lens 107 may be configured by combining Fresnel lenses.

  An image intensifier (I.I) 108 is an image intensifier tube and amplifies received light. As a result, the CMOS image sensor 110 can receive the amplified light and can widen the sensitivity bandwidth with respect to light and dark. The image intensifier 108 can multiply the light, for example, on the order of several thousand times. The image intensifier 108 is an example of an optical amplification unit. The image intensifier 108 is supplied with power from a high voltage power source.

  The control circuit 109 outputs a control signal to the image intensifier 108. The control signal controls the operation of the image intensifier 108. The image intensifier 108 performs an operation such as opening or blocking of a gate (light shutter) according to a control signal.

  A CMOS (Complementary Metal Oxide Semiconductor) image sensor 110 has a sensor main body 113, and the sensor main body 113 passes through a relay lens 107 and converts a plurality of light images formed on an imaging surface into electric signals by photoelectric conversion. It has a pixel. The CMOS image sensor 110 is an example of an image sensor. The CMOS image sensor 110 outputs the generated electrical signal to the FPGA 112, for example. On the imaging surface of the CMOS image sensor 110, the light split by the diffraction grating 106 is imaged. The CMOS image sensor 110 has a drive circuit 111, and the drive circuit 111 reads data and the like.

  An FPGA (Field Programmable Gate Array) 112 is a programmable LSI (integrated circuit), and performs data processing on the acquired image. The FPGA 112 writes data to the RAM 114 and reads data from the RAM 114. The FPGA 112 also selects which RAM 114 out of a plurality of RAMs 114 is to perform data processing. The FPGA 112 receives the electrical signal generated by the CMOS image sensor 110 and causes the RAM 114 to record the spectral data of the subject as hyperspectral data (HSD).

  The RAM 114 temporarily stores data related to the acquired image. The RAM 114 records subject spectral data as HSD. The HSD has an image area of 640 × 800 pixels, for example, and includes spectral information of a plurality of bands (wavelength areas) for each pixel. That is, each pixel has a three-dimensional data set of (x, y, λ). Here, x and y represent the position of the image plane, and λ represents the wavelength. The spectral information for each pixel can be read out individually.

  The FPGA 112 calculates the position (x, y) of the image plane of each pixel based on the electrical signal output from the CMOS image sensor 110. The FPGA 112 associates the position (x, y) of the image plane of the pixel with the wavelength λ. Note that, as the slit 104A moves in the Y-axis direction, the position of the wavelength λ also moves in the Y-axis direction on the imaging surface. Therefore, the correspondence between the position (x, y) of the pixel image plane and the wavelength λ is as follows. This is performed in association with the position information of the slit 104A in the electronic slit 104.

  The FPGA 112 calculates a physical quantity distribution on the image plane for each of a plurality of wavelength regions based on a three-dimensional data set of (x, y, λ) of each pixel. Then, the FPGA 112 generates a moving image for each of a plurality of wavelength regions, based on the position (x, y) of the image plane of the pixel having the wavelength λ and the position of the slit 104A in the electronic slit 104. The FPGA 112 is an example of an image generation unit.

  The wavelength calibration unit 116 outputs wavelength calibration light and irradiates the light receiving lens 102 and the optical system such as the electronic slit 104 with the light.

  The CPU 120 compares the calibration spectrum data acquired using the light output from the wavelength calibration unit 116 with the reference spectrum data stored in advance, and corrects the spectrum data obtained at the time of photographing based on the comparison result. . By using the wavelength calibrating unit 116, it is possible to correct a wavelength shift caused by vibration or a change with time of each element.

  The light source of the wavelength calibration unit 116 is, for example, a discrete spectrum light source including a reference wavelength having a sharp wavelength distribution, and the LED 174 is used in this embodiment. The wavelength calibration may be performed based on the absorption spectrum.

  The sensitivity calibration light source 118 is a continuous spectrum light source such as a halogen lamp. When performing sensitivity calibration, the sensitivity calibration light source 118 outputs light for sensitivity calibration and irradiates the light receiving lens 102 and the optical system such as the electronic slit 104 with the light. The sensitivity of the CMOS image sensor 110 changes due to adhering dirt, device aging, and temperature change. By calibrating the sensitivity, deviations in characteristics can be corrected.

  A CPU 120 (Central Processing Unit) functions as an arithmetic processing device and a control device according to a program, and can control processing of each component provided in the hyperspectral camera 100.

  The I / F circuit 130 transmits and receives data according to a standard such as Camera Link and Gigabit Ethernet (registered trademark).

  The illuminance sensor 160 receives light from the surrounding environment. Based on the amount of received light, feedback of the observation environment of the hyperspectral camera 100 is performed, and the multiplication factor of the image intensifier 108 is adjusted. By providing a system for receiving ambient light separately from the system using the CMOS image sensor 110, long-time exposure in the CMOS image sensor 110 becomes unnecessary, and deterioration can be prevented.

  The video monitor 150 can visually display the result calculated by the FPGA 112. The video monitor 150 can display the distribution of physical quantities (light intensity) on the image plane for each of a plurality of wavelength regions.

  Next, the image intensifier 108 will be described. FIG. 5 is an explanatory diagram showing the image intensifier 108 according to the present embodiment. The image intensifier 108 can detect extremely weak light, and can multiply and visualize it as a contrasted image. The image intensifier 108 includes an incident window 181 through which light enters an end and an output window 185 through which light exits.

  In the image intensifier 108, the light imaged on the photocathode 182 is converted into electrons. The electrons are accelerated by the voltage between the photocathode 182 and the MCP (Micro Channel Plate) 183 and enter each channel of the MCP 183. The incident electrons are repeatedly collided several tens of times by the voltage gradient at both ends of the MCP 183, thereby increasing secondary electrons and releasing a large number of electrons from the output end of the MCP 183. Furthermore, electrons are accelerated by the voltage between the output surface of the MCP 183 and the phosphor screen 184 and collide with the phosphor screen 184. Finally, according to the image intensifier 108, it is possible to obtain an output image enhanced by about 1 to 10 million times (depending on the number of stages of the MCP 183) with respect to the incident optical image.

Next, the wavelength calibration unit 116 will be described.
As shown in FIG. 6, the wavelength calibration unit 116 includes a plurality of wavelength calibration light sources 170 that output different wavelengths, a diffusion plate 172, and the like. As shown in FIG. 7, the wavelength calibration light source 170 includes, for example, an LED (Light Emitting Diode) 174, a BPF (Band Pass Filter) 176, a lens 178, and the like. FIG. 6 is an explanatory diagram showing the wavelength calibration unit 116 according to the present embodiment. FIG. 7 is an explanatory diagram showing the wavelength calibration light source 170 according to this embodiment. The light output from the LED 174 of the wavelength calibration light source 170 passes through the BPF 176 and is irradiated to the outside through the lens 178. The diffusion plate 172 is a plate member that allows light output from the wavelength calibration light source 170 to pass through while diffusing.

  The wavelength of the LED 174 changes depending on the temperature. FIG. 8A is a graph showing the relationship between the emission intensity of the LED 174 and the wavelength, and shows how the wavelength distribution of the LED 174 changes due to a temperature change. FIG. 8B is a graph showing the relationship between the transmittance of the BPF 176 and the wavelength. The BPF 176 has a characteristic of transmitting the reference wavelength (for example, peak wavelength) of the LED 174 and cutting the wavelength distribution on the low frequency side and high frequency side of the reference wavelength (for example, peak wavelength). By combining the LED 174 and the BPF 176 in the wavelength calibration light source 170, as shown in FIG. 8C, light in a certain wavelength region can be output even when the wavelength distribution changes due to a temperature change. FIG. 8C is a graph showing the relationship between the emission intensity of the LED 174 and the wavelength. As a result, in this embodiment, it is possible to realize a spectral light source with less wavelength change by suppressing the temperature characteristics of the LED 174.

  When the hyperspectral camera 100 is a built-in type such as an in-vehicle sensor that cannot be regularly maintained by an administrator or a user, calibration by the wavelength calibration unit 116 may be performed automatically. When the hyperspectral camera 100 is used as a measuring instrument that can be regularly maintained by an administrator or a user, the hyperspectral camera 100 has a configuration that allows the administrator or the user to perform a calibration operation.

[2. Operation of one embodiment]
Next, the operation of the hyperspectral camera 100 according to an embodiment of the present invention will be described. FIG. 9 is a flowchart showing the operation of the hyperspectral camera 100 according to the present embodiment.

  First, the slit 104A of the electronic slit 104 is set to the lowest end Y = y0 (step S11). Then, image data on the CMOS image sensor 110 when the slit 104A is at y0 is acquired (step S12). The linear light in the x direction from the slit 104 </ b> A is dispersed in the y direction by the diffraction grating 106, and forms a two-dimensional image on the imaging surface of the CMOS image sensor 110. Image data of the formed image can be acquired.

  Next, using the wavelength table, the coordinates in the y direction on the CMOS image sensor 110 are converted into the wavelength λ (step S13). A spectral spectrum intensity in the wavelength direction is projected in the y direction on the CMOS image sensor 110 at a certain position of the slit 104A. The wavelength table is a table showing a correspondence relationship between pixel positions in the y direction and projected wavelengths, and has table data for each position of the slit 104A.

  Conventionally, since the slit position is fixed with respect to the image sensor, there is only one wavelength table. On the other hand, in the hyperspectral camera 100 of the present embodiment, since the slit 104A is moved electronically, one wavelength table is associated with each slit position.

  Then, hyperspectral data (x, y0, l (λ)) based on the spectrum when the slit 104A is at y0 is acquired (step S14). Hyperspectral data (HSD) is a three-dimensional data set (x, y0, l (λ)) having spectral spectral intensity information at each pixel of a two-dimensional image.

  Next, the position of the slit 104A is moved by Δy in the y-axis direction (step S15). Then, Steps S12 to S15 described above are repeated to accumulate as a data set of HSD (x, yn, l (λ)) until the position of the slit 104A is Y = ymax. Here, n is an integer from 0 to max.

  Then, by using the accumulated HSD (x, yn, l (λ)), (x, y) images corresponding to each λ can be reconstructed. For example, FIG. 10 shows pixels arranged in the X-axis direction and the Y-axis direction, and shows that each pixel includes spectral information that includes the relationship between the wavelength region and the light intensity. Moreover, as shown in FIG. 11, the distribution on the plane of the light intensity in each wavelength region λ can be displayed. FIG. 11 shows a planar distribution corresponding to an arbitrary wavelength region in which the wavelength region λ is between 400 nm and 800 nm. FIG. 5 illustrates that a plane distribution in an arbitrary wavelength region can be synthesized. By combining the planar distributions of arbitrary wavelength regions, it is possible to display on the PC 140 or the video monitor 150 with high accuracy. 10 and 11 are explanatory diagrams showing the definition of hyperspectral data.

  As described above, according to the present embodiment, since the position of the slit 104A can be scanned at high speed in the electronic slit 104, one set of HSD can be acquired in a short time. As a result, since a set of HSDs that can be acquired per unit time can be increased, a hyperspectral image can be obtained as a moving image.

  Conventionally, the hyperspectral camera 10 has a scanning mechanism 20 in which the slit 4 and the CCD 11 are mounted on the same stage as shown in FIG. The scanning mechanism 20 is moved in one direction by the digital servo motor, thereby acquiring a two-dimensional image. FIG. 12 is a block diagram showing a conventional hyperspectral camera 10. The hyperspectral camera 10 includes a light receiving lens 2, a slit 4, a diffraction grating 6, a relay lens 7, a CCD sensor 11, a scanning mechanism 20, a digital servo motor 22, and the like. Then, image data is output from the hyperspectral camera 10 to the PC 40 or the like.

  Since the conventional hyperspectral camera 10 is a mechanical scanning method, it takes time to obtain a set of hyperspectral data, and the number of hyperspectral data that can be acquired per unit time is limited. For example, the conventional hyperspectral camera 10 takes 10 to several tens of seconds or several minutes on the order to acquire a set of hyperspectral data. On the other hand, according to the present embodiment, as described above, by using the electronic slit 104, the hyperspectral data includes time information in addition to three-dimensional information such as two-dimensional space and wavelength information, and is reproduced as a moving image. Possible hyperspectral data can be obtained.

  As a result, conventionally, the hyperspectral camera 10 has been used in a limited field, but according to the hyperspectral camera 100 of the present embodiment, the fields that can be utilized can be expanded. That is, it is possible to perform unprecedented object recognition and characteristic analysis by photographing moving objects or objects whose shapes change with time as subjects and measuring these objects using hyperspectral technology. For example, the present invention can be applied to object recognition based on spatial shape and spectrum measurement of moving objects, spectrum measurement of flames and the like, observation of distribution changes thereof, visualization of bacterial characteristics and spread thereof, and the like.

  Further, the hyperspectral camera 100 can be used as a safe operation support sensor in the automobile industry, a driver's physical condition monitoring, a hyperspectral remote sensing in the aerospace field, and a spectrum sensor for planetary exploration. Furthermore, the hyperspectral camera 100 can be used for identification of fluorescent proteins in the bio field, visualization of spectrum endoscopes and cancers in the medical field, and human authentication in security systems. Furthermore, in the military industry, the hyperspectral camera 100 can be used as a special camera for object identification for soldiers, a sensor mounted on a missile, and a sensor for unmanned reconnaissance.

  The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings, but the present invention is not limited to such examples. It is obvious that a person having ordinary knowledge in the technical field to which the present invention pertains can come up with various changes or modifications within the scope of the technical idea described in the claims. Of course, it is understood that these also belong to the technical scope of the present invention.

  In the hyperspectral camera 100 of the above-described embodiment, the electronic slit 104 is used as the variable slit member. However, in this embodiment, a micro-electro-mechanical systems (MEMS) slit may be used as the variable slit member. . When installing the MEMS slit, the hyperspectral camera 200 is further provided with a MEMS mirror that works in conjunction with the MEMS slit.

DESCRIPTION OF SYMBOLS 100, 200 Hyperspectral camera 102 Light-receiving lens 103,178 Lens 104 Electronic slit 104A Slit 104B Light-shielding part 105 Electronic slit drive circuit 106 Diffraction grating 107 Relay lens 108 Image intensifier 109 Control circuit 110 CMOS image sensor 111 Drive circuit 112 FPGA
113 Sensor body 114 RAM
116 Wavelength calibration unit 118 Sensitivity calibration light source 120 CPU
130 I / F circuit 140 PC
150 Video Monitor 152 Video Output Conversion Circuit 160 Illuminance Sensor 170 Wavelength Calibration Light Source 172 Diffuser 174 LED
176 BPF (band pass filter)
181 Incident window 182 Photocathode 183 MCP (Micro Channel Plate)
184 phosphor screen 185 output window

Claims (6)

A slit is formed to transmit light from the subject as linear light parallel to the first direction, and the slit is formed from one end to the other end in a second direction perpendicular to the first direction. A variable slit member whose position moves within the member;
A spectroscopic optical element that splits light transmitted through the slit into a plurality of wavelength regions defined by a hyperspectrum;
An image sensor having a plurality of pixels that receive light for each wavelength region dispersed by the spectroscopic optical element and photoelectrically convert it to generate an electrical signal;
The light intensity for each wavelength region is calculated based on the electrical signal, and the position of the slit in the variable slit member and the position of the light for each wavelength region received by the image sensor in the image sensor. A hyperspectrum, comprising: an image generation unit configured to generate one two-dimensional image for each wavelength region when the slit moves once from the one end side to the other end side based on a relationship; Imaging device.   The hyper-spectral imaging apparatus, wherein the variable slit member forms the slit by electrically transmitting and blocking light by liquid crystal according to voltage application, and electrically moves the position of the slit.   The optical amplifying unit that amplifies the intensity of the light for each wavelength region spectrally separated by the spectroscopic optical element and irradiates the image pickup element with the amplified light is further provided. Hyperspectral imaging device. A light emitting diode that emits light toward the variable slit member, the spectroscopic optical element, and the imaging element;
A bandpass filter that passes the peak wavelength of the light emitted by the light emitting diode;
The hyperspectral imaging device according to any one of claims 1 to 3, further comprising a wavelength calibration light source having:   The hyperspectral imaging apparatus according to claim 4, further comprising a diffusion plate that diffuses and transmits light that has passed through the bandpass filter of the wavelength calibration light source. The variable slit member forms a slit that transmits light from the subject as linear light parallel to the first direction and transmits the slit in a second direction perpendicular to the first direction from the other end to the other end. Moving the position of the slit to the side within the member;
A spectroscopic optical element splits the light transmitted through the slit into a plurality of wavelength regions defined by a hyper spectrum;
An imaging device having a plurality of pixels that receive light in each wavelength region spectrally separated by the spectroscopic optical element and photoelectrically convert the pixel to generate an electrical signal;
The image generation unit calculates the intensity of light for each wavelength region based on the electrical signal, and the position of the slit in the variable slit member and the imaging of the light for each wavelength region received by the imaging device A step of generating one two-dimensional image for each wavelength region when the slit moves once from the one end side to the other end side based on a relationship with a position in the element. Hyperspectral imaging method.

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