JP2009135907A - Image capturing device and image capturing system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image capturing device capable of providing an image of desired definition color components corresponding to the penetration depth of light to a subject. <P>SOLUTION: The present invention relates to an image capturing system comprising an image capturing device. The image capturing device includes a plurality of first light receiving elements that receive light in a first wavelength region and a plurality of second light receiving elements that receive light in a wavelength region having a penetration depth in relation to a subject that is less than the penetration depth of light in the first wavelength region. The number of second light receiving elements is greater than the number of first light receiving elements. The ratio of the number of second light receiving elements to the number of first light receiving elements may be set according to a ratio of the penetration depth of light in the first wavelength region to the penetration depth of light in a second wavelength region, which is the light in the wavelength region received by the second light receiving elements. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an imaging device and an imaging system. The present invention particularly relates to an imaging system that captures an image and an imaging device for the imaging system.

There is known a living body observation apparatus that can image blood vessels and the like on the surface of the mucous membrane in a living body with good contrast (see, for example, Patent Document 1). There is also known an electronic endoscope apparatus that obtains a normal image, a narrow-band light observation image, and an autofluorescence observation image with high image quality and sufficient color reproduction (see, for example, Patent Document 2).
JP 2007-29555 A JP 2007-50106 A

  When a living body such as a human body, particularly the inside thereof is imaged, an image in which the luminance value of the R component is extremely larger than the luminance values of other color components is often obtained. On the other hand, image information based on color components other than the R component may be important for medical images intended to support a doctor's procedure. In the image sensor array described in the above-mentioned patent document, there are cases where image information with color components other than the important R component cannot be obtained sufficiently. Further, the light of the B component or the G component contains more information on the biological surface layer than the light of the R component. In the image pickup device array described in the above-mentioned patent document, there are cases where image information on the surface layer by the B component or the G component cannot be obtained with sufficient resolution.

  In order to solve the above problems, according to a first aspect of the present invention, an imaging system including an imaging device, the imaging device receiving a light in a first wavelength region, a first wavelength, A second light receiving element that receives light in a wavelength region having a smaller depth of penetration to the subject than the light in the region, and the number of second light receiving elements is greater than the number of first light receiving elements.

  The ratio of the number of the second light receiving elements to the number of the first light receiving elements is the ratio of the depth of light in the first wavelength region to the depth of light in the second wavelength region that is the wavelength region received by the second light receiving element. It may be determined according to the ratio. The ratio of the number of second light receiving elements to the number of first light receiving elements may be substantially the same as the ratio of the light penetration depth of the first wavelength region to the light penetration depth of the second wavelength region.

  The first light receiving element and the second light receiving element receive reflected light from the living body, the second light receiving element receives light in the blue wavelength region, and the first light receiving element receives light in the red wavelength region. Good. The first light receiving element and the second light receiving element receive reflected light from the human body, the second light receiving element receives light in the blue wavelength region, and the first light receiving element receives light in the red wavelength region. Good.

  The first light receiving element and the second light receiving element receive reflected light from the living body, the second light receiving element receives light in the green wavelength region, and the first light receiving element receives light in the red wavelength region. Good. The first light receiving element and the second light receiving element may receive reflected light from a human body including blood components.

  You may further provide the image generation part which produces | generates the image of a human body based on the light reception amount which the 1st light receiving element and the 2nd light receiving element received.

  The imaging device receives light in a third wavelength region that is different from the first wavelength region and the second wavelength region and has a third wavelength region that has a smaller depth of penetration to the subject than the light in the first wavelength region. The light receiving element further includes three light receiving elements, and the ratio of the number of the third light receiving elements to the number of the first light receiving elements is in accordance with a ratio of the light penetration depth of the first wavelength region to the light penetration depth of the third wavelength region. May be determined.

  According to the second aspect of the present invention, the imaging device is a first light receiving element that receives light in the first wavelength region, and light in a wavelength region that has a smaller depth of penetration to the subject than the light in the first wavelength region. The number of second light receiving elements is greater than the number of first light receiving elements.

  According to a third aspect of the present invention, there is provided an imaging system including an imaging device, the imaging device receiving a light in the first wavelength region and a spectral intensity smaller than the spectral intensity in the first wavelength region. The number of the second light receiving elements is greater than the number of the first light receiving elements.

  The second light receiving element may receive light in a second wavelength region that is a wavelength region having a spectral reflectance smaller than that of the subject in the first wavelength region. The ratio of the number of second light receiving elements to the number of first light receiving elements may be determined according to the ratio of the spectral reflectance in the first wavelength region to the spectral reflectance in the second wavelength region. The ratio of the number of second light receiving elements to the number of first light receiving elements may be substantially the same as the ratio of the spectral reflectance in the first wavelength region to the spectral reflectance in the second wavelength region.

  The light irradiation unit for irradiating the subject with light is further provided, and the ratio of the number of the second light receiving elements to the number of the first light receiving elements is determined by the spectral reflectance in the second wavelength region and the spectrum of the light irradiated by the light irradiation unit on the subject. It may be substantially the same as the ratio of the product of the spectral reflectance in the first wavelength region and the spectral intensity of the light irradiated to the subject by the light irradiation unit with respect to the product of the intensity. The ratio of the number of the second light receiving elements to the number of the first light receiving elements is the spectral reflectance in the second wavelength region, the spectral intensity of the light irradiated to the subject by the light irradiation unit, and the light receiving sensitivity of the second light receiving element. The ratio of the product of the spectral reflectance in the first wavelength region, the spectral intensity of the light irradiated to the subject by the light irradiation unit, and the light receiving sensitivity of the first light receiving element to the product may be substantially the same.

  The first light receiving element and the second light receiving element receive reflected light from the living body, the second light receiving element receives light in the blue wavelength region, and the first light receiving element receives light in the red wavelength region. Good. The first light receiving element and the second light receiving element receive reflected light from the human body, the second light receiving element receives light in the blue wavelength region, and the first light receiving element receives light in the red wavelength region. Good. The first light receiving element and the second light receiving element receive reflected light from the living body, the second light receiving element receives light in the green wavelength region, and the first light receiving element receives light in the red wavelength region. Good. The first light receiving element and the second light receiving element may receive reflected light from a human body including blood components.

  You may further provide the image generation part which produces | generates the image of a human body based on the light reception amount which the 1st light receiving element and the 2nd light receiving element received. The imaging device receives a light in a third wavelength region different from the first wavelength region and the second wavelength region, and receives light in a third wavelength region having a spectral intensity smaller than the spectral intensity in the first wavelength region. The ratio of the number of the third light receiving elements to the number of the first light receiving elements is determined according to the ratio of the spectral reflectance in the first wavelength region to the spectral reflectance of the subject in the third wavelength region. Good.

  According to the fourth aspect of the present invention, the imaging device is a first light receiving element that receives light in the first wavelength region, and receives light in a wavelength region having a spectral intensity smaller than the spectral intensity in the first wavelength region. The number of second light receiving elements is greater than the number of first light receiving elements.

  It should be noted that the above summary of the invention does not enumerate all the necessary features of the present invention. In addition, a sub-combination of these feature groups can also be an invention.

  Hereinafter, the present invention will be described through embodiments of the invention, but the following embodiments do not limit the invention according to the claims. In addition, not all the combinations of features described in the embodiments are essential for the solving means of the invention.

  FIG. 1 shows an example of the configuration of an imaging system 10 according to this embodiment together with a specimen 20. The imaging system 10 includes an endoscope 100, an image generation unit 140, an output unit 180, a control unit 105, a light irradiation unit 150, and an ICG injection unit 190. In FIG. 1, the A part shows the distal end part 102 of the endoscope 100 in an enlarged manner.

  The ICG injection unit 190 injects indocyanine green (ICG), which is a luminescent substance, into the specimen 20 that is an example of a subject. In addition, although ICG is illustrated as a luminescent substance in this embodiment, you may use fluorescent substances other than ICG as a luminescent substance.

  ICG is excited by infrared rays having a wavelength of 750 nm, for example, and emits a broad spectrum of fluorescence centering on 810 nm. When the specimen 20 is a living body, the ICG injection unit 190 injects ICG into the blood vessel of the living body by intravenous injection. The imaging system 10 images a blood vessel in a living body with luminescence light from the ICG. Note that the luminescence light is an example of light in a specific wavelength region, and includes fluorescence and phosphorescence. In addition, luminescence light, which is an example of light from a subject, includes luminescence light by chemiluminescence, triboluminescence, and thermoluminescence in addition to photoluminescence by light such as excitation light.

  The ICG injection unit 190 injects ICG into the specimen 20 so that the ICG concentration in the living body is maintained substantially constant under the control of the control unit 105, for example. The specimen 20 may be a living body such as a human body, and is an imaging target of an image processed by the imaging system 10. An object such as a blood vessel exists inside the specimen 20.

  The endoscope 100 includes an imaging unit 110, a light guide 120, and a forceps port 130. The distal end portion 102 of the endoscope 100 has a lens 112 as a part of the imaging unit 110. Further, the distal end portion 102 has an emission port 124 as a part of the light guide 120. The distal end portion 102 of the endoscope 100 has a nozzle 138.

  A forceps 135 is inserted into the forceps port 130, and the forceps port 130 guides the forceps 135 to the distal end portion 102. Note that the forceps 135 may have various tip shapes. In addition to the forceps, various treatment tools for treating a living body may be inserted into the forceps port 130. The nozzle 138 delivers water or air.

  The light irradiation unit 150 generates light irradiated from the distal end portion 102 of the endoscope 100. The light generated by the light irradiation unit 150 irradiates the sample 20 with infrared rays as an example of excitation light that is light in a wavelength region that excites a luminescent substance contained in the sample 20 to emit light in a specific wavelength region. Includes irradiation light. The irradiation light includes, for example, component light of R component, G component, and B component.

  The light guide 120 is formed of an optical fiber, for example. The light guide 120 guides the light generated by the light irradiation unit 150 to the distal end portion 102 of the endoscope 100. The light guide 120 can include an emission port 124 provided in the distal end portion 102. The light generated by the light irradiation unit 150 is irradiated to the specimen 20 from the emission port 124.

  The imaging unit 110 receives at least one of the light emitted from the luminescent material and the reflected light reflected by the object. The image generation unit 140 generates an image by processing the light reception data acquired from the imaging unit 110. The output unit 180 outputs the image generated by the image generation unit 140.

  The control unit 105 includes an imaging control unit 160 and a light emission control unit 170. The imaging control unit 160 controls imaging by the imaging unit 110. In addition, the light emission control unit 170 controls the light irradiation unit 150 under the control of the imaging control unit 160. For example, when the imaging unit 110 captures each component light of an infrared ray, an R component, a G component, and a B component in a time division manner, the light emission control unit 170 synchronizes the irradiation timing of each component light with the imaging timing. The light irradiated on the specimen 20 from the light irradiation unit 150 is controlled so as to cause the light irradiation to occur.

  FIG. 2 shows an example of the configuration of the imaging unit 110. The imaging unit 110 includes a lens 112, an imaging device 210, a spectral filter unit 220, and a light receiving side excitation light cut filter unit 230. The imaging device 210 includes a plurality of first light receiving elements 251 including a first light receiving element 251a, a plurality of second light receiving elements 252 including a second light receiving element 252a and a second light receiving element 252b, and a plurality of elements including a third light receiving element 253a. A third light receiving element 253 is included.

  Hereinafter, functions and operations of components included in the imaging unit 110 will be described. In the following description, in order to prevent the description from becoming complicated, the plurality of first light receiving elements 251 are collectively referred to as first light receiving elements 251 and the plurality of second light receiving elements 252 are collectively referred to as second light receiving elements. The plurality of third light receiving elements 253 may be collectively referred to as a third light receiving element 253. In addition, the plurality of first light receiving elements 251, the plurality of second light receiving elements 252, and the plurality of third light receiving elements 253 may be collectively referred to simply as light receiving elements.

  The first light receiving element 251, the second light receiving element 252, and the third light receiving element 253 receive light from the subject supplied through the lens 112. Specifically, the first light receiving element 251 receives light in a specific wavelength region and light in a first wavelength region different from the specific wavelength region. The second light receiving element 252 receives light in a second wavelength region different from the specific wavelength region. The third light receiving element 253 receives light in a third wavelength region different from the specific wavelength region, the first wavelength region, and the second wavelength region.

  The first wavelength region, the second wavelength region, and the third wavelength region are different wavelength regions, and include a wavelength region that does not include other wavelength regions. The first light receiving element 251, the second light receiving element 252, and the third light receiving element 253 are two-dimensionally arranged in a predetermined pattern.

  The spectral filter unit 220 includes a plurality of filter elements that pass one of the light in the first wavelength region, the light in the second wavelength region, and the light in the third wavelength region. Each filter element is two-dimensionally arranged according to the respective light receiving elements of the first light receiving element 251, the second light receiving element 252, and the third light receiving element 253. The individual light receiving elements receive the light that has passed through the individual filter elements. As described above, the first light receiving element 251, the second light receiving element 252, and the third light receiving element 253 receive light in different wavelength regions.

  The light receiving side excitation light cut filter unit 230 is provided at least between the subject and the second light receiving element 252 and the third light receiving element 253, and cuts light in the wavelength region of the excitation light. The second light receiving element 252 and the third light receiving element 253 receive the reflected light from the subject through the light receiving side excitation light cut filter unit 230. For this reason, the second light receiving element 252 and the third light receiving element 253 do not receive the reflected light that the excitation light reflects from the subject.

  The light-receiving-side excitation light cut filter unit 230 may cut light in the wavelength region of excitation light and light in a specific wavelength region. In this case, the second light receiving element 252 and the third light receiving element 253 do not receive the luminescence light from the subject.

  The light receiving side excitation light cut filter unit 230 may be provided between the subject and the second light receiving element 252. In this case, the light receiving side excitation light cut filter unit 230 transmits the luminescence light.

  The light receiving side excitation light cut filter unit 230 is two-dimensionally according to the respective light receiving elements of the first light receiving element 251, the second light receiving element 252, and the third light receiving element 253, similarly to the spectral filter unit 220. An array of filter elements may be included. The filter element that supplies light to the first light receiving element 251 cuts the light in the wavelength region of the excitation light and allows the light in the first wavelength region and the specific wavelength region to pass. On the other hand, the filter element that supplies light to the second light receiving element 252 cuts the light in the wavelength region of the excitation light and the light in the specific wavelength region, and passes at least the light in the second wavelength region. The filter element that supplies light to the third light receiving element 253 cuts light in the wavelength region of the excitation light and light in the specific wavelength region, and passes at least the light in the third wavelength region.

  The image generation unit 140 determines a pixel value of one pixel based at least on the amount of light received by the first light receiving element 251a, the second light receiving element 252a, the second light receiving element 252b, and the third light receiving element 253a. That is, one pixel element is formed by a two-dimensional array structure of the first light receiving element 251a, the second light receiving element 252a, the second light receiving element 252b, and the third light receiving element 253a, and the pixel element array is two-dimensionally arranged. As a result, a plurality of pixel elements are formed. The light receiving elements are not limited to the arrangement structure shown in the figure, and may be arranged in various arrangement structures.

  Note that the number of the first light receiving elements 251, the second light receiving elements 252, and the third light receiving elements 253 included in the imaging device 210 is determined according to the spectral reflectance of the subject. The number of the first light receiving elements 251, the second light receiving elements 252, and the third light receiving elements 253 included in the imaging device 210 will be described later with reference to FIG.

  FIG. 3 shows an example of spectral sensitivity characteristics of the first light receiving element 251, the second light receiving element 252, and the third light receiving element 253. Lines 330, 310, and 320 indicate spectral sensitivity distributions of the first light receiving element 251, the second light receiving element 252, and the third light receiving element 253, respectively. For example, the first light receiving element 251 is sensitive to light having a wavelength in the vicinity of 650 nm where other light receiving elements are not substantially sensitive. The second light receiving element 252 is sensitive to light having a wavelength in the vicinity of 450 nm where other light receiving elements are not substantially sensitive. The third light receiving element 253 is sensitive to light having a wavelength in the vicinity of 540 nm where other light receiving elements are not substantially sensitive.

  The first light receiving element 251 can receive light in an infrared region (for example, 810 nm) that is an example of the specific wavelength region. This spectral sensitivity characteristic depends on the characteristics of the light receiving side excitation light cut filter unit 230 and the spectral filter unit 220.

  As described above, the first light receiving element 251, the second light receiving element 252, and the third light receiving element 253 receive R component light, B component light, and G component light, respectively. The first light receiving element 251 can also receive light in the infrared region, which is an example of the specific wavelength region. In addition, the 1st light receiving element 251, the 2nd light receiving element 252, and the 3rd light receiving element 253 may be image pick-up elements, such as CCD and CMOS, as an example. The first light receiving element 251 and the second light receiving element 252 are combined according to the combination of the spectral transmittance of the light receiving side excitation light cut filter unit 230, the spectral transmittance of the filter element included in the spectral filter unit 220, and the spectral sensitivity of the imaging device itself. , And the third light receiving element 253 have spectral sensitivity characteristics indicated by a line 330, a line 310, and a line 320, respectively.

  FIG. 4 shows an example of the configuration of the light irradiation unit 150. The light irradiation unit 150 includes a light emitting unit 410 and a light source side filter unit 420. The light emitting unit 410 emits light in a wavelength region including the wavelength region of the excitation light, the first wavelength region, the second wavelength region, and the third wavelength region. In the present embodiment, the light emitting unit 410 may be a xenon lamp as an example.

  FIG. 5 shows an example of the configuration of the light source side filter unit 420. FIG. 5 shows a structure when viewed in a direction in which light is guided from the light emitting unit 410 to the light source side filter unit 420. The light source side filter unit 420 includes an irradiation light cut filter unit 520 and an excitation light cut filter unit 510. The light emission control unit 170 rotates the light source side filter unit 420 in a plane substantially perpendicular to the direction in which the light emitted from the light emitting unit 410 travels, with the central axis of the light source side filter unit 420 as the center.

  The excitation light cut filter unit 510 passes the light in the first wavelength region, the light in the second wavelength region, and the light in the third wavelength region, and cuts the light in the wavelength region of the excitation light. Irradiation light cut filter 520 passes light in the wavelength region of excitation light, light in the second wavelength region, and light in the third wavelength region. It is desirable that the irradiation light cut filter unit 520 cuts light in the first wavelength region. Note that light from the light emitting unit 410 is guided to a position shifted from the central axis of the light source side filter unit 420.

  Therefore, at the timing when the light from the light emitting unit 410 is guided to the excitation light cut filter unit 510, the light in the wavelength region of the excitation light among the light from the light emitting unit 410 is cut by the excitation light cut filter unit 510, The light in the first wavelength region, the light in the second wavelength region, and the light in the third wavelength region pass through the excitation light cut filter unit 510. Therefore, at this timing, the subject is irradiated with light in the first wavelength region, light in the second wavelength region, and light in the third wavelength region.

  On the other hand, at the timing when the light from the light emitting unit 410 is guided to the irradiation light cut filter unit 520, among the light from the light emitting unit 410, the light in the wavelength region of the excitation light, the light in the second wavelength region, and the third The light in the wavelength region passes through the irradiation light cut filter unit 520. Therefore, at this timing, the subject is irradiated with excitation light, light in the second wavelength region, and light in the third wavelength region.

  Note that the imaging unit 110 is irradiated at the timing when the light of the first wavelength region, the light of the second wavelength region, and the light of the third wavelength region, which is visible light, is irradiated under the control of the imaging control unit 160. The reflected light reflected by the specimen 20 is received. Then, the image generation unit 140 generates a visible light image based on the amount of light received by the imaging unit 110.

  In addition, the imaging unit 110 controls the imaging control unit 160 to emit luminescence light emitted from the ICG inside the subject at the timing when the excitation light, the light in the second wavelength region, and the light in the third wavelength region are irradiated. And the reflected light of the light in the second wavelength region and the light in the third wavelength region by the specimen 20 is received. Then, the image generation unit 140 generates a luminescence light image based on the amount of luminescence light received by the imaging unit 110, and the amount of light received in the second wavelength region and the third wavelength region. A visible light image is generated based on the amount of light received in the first wavelength region received by the imaging unit 110 at the timing. Note that a generation method for generating the image generation unit 140 image will be described with reference to FIG.

  FIG. 6 shows an example of the spectral intensity of light emitted from the light irradiation unit 150 and the spectral reflectance of the subject. A line 710 indicates a spectral intensity distribution of light generated by a xenon lamp as an example of the light emitting unit 410, and shows a comparatively gentle spectral intensity in the visible light region.

  A line 720 indicates the spectral reflectance of the stomach mucous membrane as an example of the subject. As apparent from this distribution, the reflectance in the first wavelength region, which is the wavelength region received by the first light receiving element 251, is the spectral reflectance in the second wavelength region received by the second light receiving element 252 and the third light receiving element. 253 is greater than the spectral reflectance in the third wavelength region received.

  Therefore, the second light receiving element 252 receives light in the second wavelength region, which is a wavelength region having a spectral reflectance smaller than the spectral reflectance of the subject in the first wavelength region. The third light receiving element 253 receives light in the third wavelength region, which is a wavelength region having a spectral reflectance smaller than the spectral reflectance of the subject in the first wavelength region. Therefore, if the spectral intensity of the light emitted from the light irradiation unit 150 is substantially constant as indicated by the line 710, the second light receiving element 252 has a wavelength region having a spectral intensity smaller than the spectral intensity in the first wavelength region. The light will be received. The third light receiving element 253 receives light in a wavelength region having a spectral intensity smaller than the spectral intensity in the first wavelength region.

  The ratio of the number of the second light receiving elements 252 to the number of the first light receiving elements 251 and the ratio of the number of the third light receiving elements 253 to the number of the first light receiving elements 251 are determined according to the relative light receiving intensity of each light receiving element. The Specifically, for the first light receiving element 251, a value obtained by integrating the relative light receiving intensity indicating a value obtained by multiplying the spectral sensitivity indicated by the line 330 in FIG. 3 and the spectral reflectance of the subject indicated by the line 720 over the wavelength region, The relative light receiving intensity of the first light receiving element 251 is calculated. Similarly, for the second light receiving element 252, a value obtained by integrating the relative light receiving intensity indicating a value obtained by multiplying the spectral sensitivity indicated by the line 310 in FIG. 3 and the spectral reflectance of the subject indicated by the line 720 over the wavelength region is expressed as follows: The relative light receiving intensity of the second light receiving element 252 is calculated. Similarly, with respect to the third light receiving element 253, a value obtained by integrating the relative light receiving intensity indicating a value obtained by multiplying the spectral sensitivity indicated by the line 320 in FIG. 3 and the spectral reflectance of the subject indicated by the line 720 over the wavelength region, The relative light receiving intensity of the third light receiving element 253 is calculated.

  The number of the first light receiving elements 251, the number of the second light receiving elements 252, and the number of the third light receiving elements 253 are such that the ratio of the number of the third light receiving elements 253 to the number of the first light receiving elements 251 is the second light receiving element. The ratio of the relative light receiving intensity of the first light receiving element 251 to the relative light receiving intensity of 252 is substantially the same, and the ratio of the number of the third light receiving elements 253 to the number of the first light receiving elements 251 is relative to the third light receiving element 253. It is determined to be substantially the same as the ratio of the relative light receiving intensity of the first light receiving element 251 to the light receiving intensity. Thus, the ratio of the number of the second light receiving elements 252 to the number of the first light receiving elements 251 is determined according to the ratio of the spectral reflectance in the first wavelength region to the spectral reflectance in the second wavelength region.

  The ratio of the number of the second light receiving elements 252 to the number of the first light receiving elements 251 and the ratio of the number of the third light receiving elements 253 to the number of the first light receiving elements 251 are the light emitted from the light irradiation unit 150 to the subject. May be determined according to the emission spectrum. For example, the value obtained by integrating the spectral sensitivity of each light receiving element, the spectral reflectance of the subject, and the spectral intensity of the light emitted from the light emitting unit 410 onto the subject is integrated over the wavelength region as the relative light receiving intensity of each light receiving element. To do. The ratio of the number of the second light receiving elements 252 to the number of the first light receiving elements 251 and the number of the first light receiving elements 251 according to the above-described method using the relative light receiving intensity weighted by the spectral intensity of the light emitted from the light irradiation unit 150 to the subject. The ratio of the number of third light receiving elements 253 to the number of first light receiving elements 251 is determined.

  Thus, the ratio of the number of the second light receiving elements 252 to the number of the first light receiving elements 251, the spectral reflectance in the second wavelength region, the spectral intensity of the light emitted to the subject by the light emitting unit 410, and the second The ratio of the product of the spectral reflectance in the first wavelength region, the spectral intensity of the light emitted from the light emitting unit 410 to the subject, and the light receiving sensitivity of the first light receiving element 251 with respect to the product of the light receiving sensitivity of the light receiving element 252 and the approximate value. Make the same.

  According to the spectral sensitivity illustrated in FIG. 3 and the spectral reflectance illustrated in FIG. 6, the relative light reception intensity of the first light receiving element 251, the relative light reception intensity of the second light receiving element 252, and the relative light reception intensity of the third light receiving element 253. Is approximately 2: 1: 1. Therefore, in the present embodiment, the light receiving elements are arranged in the imaging device 210 so that the number of the first light receiving elements 251, the number of the second light receiving elements 252, and the number of the third light receiving elements 253 are 2: 2: 1. .

  When the first light receiving element 251, the second light receiving element 252, and the third light receiving element 253 receive reflected light from a living body such as a human body containing a red blood component such as hemoglobin, the wavelength region of the B component The number of the second light receiving elements 252 that receive the light of λ and the number of the third light receiving elements 253 that receive the light in the wavelength region of the G component are the number of the first light receiving elements 251 that respectively receive the light in the wavelength region of the R component Do more. Note that the ratio of the number of second light receiving elements 252 to the number of first light receiving elements 251 may be substantially the same as the ratio of the spectral reflectance in the first wavelength region to the spectral reflectance in the second wavelength region. .

  FIG. 7 shows an example of the imaging timing by the imaging unit 110 and an image generated by the image generation unit 140. The imaging control unit 160 causes the imaging unit 110 to capture images at times t600, t601, t602, t603,. In addition, the light emission control unit 170 causes the light emitted from the light emitting unit 410 to irradiate the subject through the excitation light cut filter unit 510 at the first timing including the times t600, t601, and t603 by the timing control by the imaging control unit 160. . In this way, the light emission control unit 170 irradiates the subject with light in a wavelength region including the first wavelength region, the second wavelength region, and the third wavelength region at the first timing.

  The imaging control unit 160 irradiates the subject with light in the wavelength region including the first wavelength region, the second wavelength region, and the second wavelength region at the first timing, and reflects the reflected light from the subject. The first light receiving element 251 receives light in the first wavelength region, the second light receiving element 252 receives light in the second wavelength region of the reflected light, and the third light receiving light in the third wavelength region in the reflected light. The element 253 receives light. In this way, the imaging control unit 160 causes the first light receiving element 251 to receive the light in the first wavelength region from the subject at the first timing, and the second light receiving element 252 to receive the light in the second wavelength region from the subject. The third light receiving element 253 receives light in the third wavelength region from the subject.

  Further, at the second timing including time t <b> 602, the light emission control unit 170 irradiates the subject with the light emitted from the light emitting unit 410 through the irradiation light cut filter unit 520 by the timing control by the imaging control unit 160. In this manner, the light emission control unit 170 irradiates the subject with light in a wavelength region including the excitation light, the second wavelength region, and the third wavelength region at the second timing.

  Then, at the second timing, the imaging control unit 160 causes the first light receiving element 251 to receive the light in the specific wavelength region emitted from the subject. That is, the imaging control unit 160 causes the first light receiving element 251 to receive light in a specific wavelength region from the subject at the second timing.

  In this way, the control unit 105 irradiates the subject with the excitation light, the light of the second wavelength region, and the light of the third wavelength region without irradiating the subject with the light of the first wavelength region at the second timing. Then, the light of the specific wavelength region emitted from the subject is received by the first light receiving element 251, and the light of the second wavelength region among the reflected light reflected from the subject is received by the second light receiving element 252. Of these, the third light receiving element 253 receives light in the third wavelength region. The wavelength region of the excitation light is a wavelength region different from any of the first wavelength region, the second wavelength region, and the third wavelength region, and is in the first wavelength region, the second wavelength region, and the third wavelength region. Includes wavelength ranges not included.

  As described above, the control unit 105 controls the wavelength region of light received by the first light receiving element 251, the second light receiving element 252, and the third light receiving element 253. Then, the image generation unit 140 generates an image of the subject based on the amount of light received by the light receiving element at each timing.

  The image generation unit 140 generates a visible light image 620a, a visible light image 620b, and a visible light image 620d based on the amount of light received by the light receiving element at timings represented by time t600, time t601, and time t603. Generate. The visible light image 620a includes a blood vessel image 622a and a blood vessel image 624a, the visible light image 620b includes a blood vessel image 622b and a blood vessel image 624b, and the visible light image 620d includes a blood vessel image 622d and a blood vessel image 624d.

  Note that the visible light image 620a, the visible light image 620b, and the visible light image 620d include a surface image that is an image of the surface of the substance in addition to the blood vessel image. As described above, the image generation unit 140 receives the light in the first wavelength region received by the first light receiving element 251 at the first timing and the light in the second wavelength region received by the second light receiving element 252 at the first timing. Thus, a subject image at the first timing is generated.

  Further, the image generation unit 140 generates a luminescence light image 620c including a blood vessel image 622c, a blood vessel image 624c, and a blood vessel image 626c based on the amount of light received by the light receiving element at the timing represented by time t602. In addition, the image generation unit 140 receives the amount of light received by the first light receiving element 251 at the timing represented by time t601, and receives the light received by the second light receiving element 252 and the third light receiving element 253 at the timing represented by time t602. Based on the quantity, a visible light image 630c is generated. In this way, the image generation unit 140 generates an image of the human body based on the amount of light received by the first light receiving element 251, the second light receiving element 252, and the third light receiving element 253.

  As described above, the image generation unit 140 uses the light in the second wavelength region received by the second light receiving element 252 at the second timing, and the light in the first wavelength region received by the first light receiving element 251 at the first timing. And a subject image at the second timing. Therefore, the image generation unit 140 can generate a visible light image even at the timing when the luminescence light image is captured. The output unit 180 can provide a video without frame dropping by continuously displaying the visible light images 620a, 620b, 630c, 620d,.

  When the specimen 20 is a living body including red blood such as a human body, the spatial frequency component of the R component in the visible light image is often smaller than the spatial frequency components of the G component and the B component. For this reason, the degree of deterioration of the video due to the drop of the R component is often smaller than when the G component and the B component are dropped. For this reason, it is possible to reduce the tingling sensation in the video as compared with the case where the G component and the B component are dropped. Therefore, the imaging system 10 may be able to provide a visible light image that is substantially free of frames as the video content.

  As described above, according to the imaging system 10, the luminescence light image 620c can be captured by the luminescence light in the infrared region generated from the specimen 20 by the excitation light in the infrared region. Excitation light having a wavelength longer than that of visible light is less likely to be absorbed by the substance than visible light. Therefore, the excitation light penetrates deeper into the substance (for example, about 1 cm) than visible light and causes luminescence light to be generated in the specimen 20. In addition, since the luminescence light has a longer wavelength than the excitation light, it easily reaches the material surface. For this reason, according to the imaging system 10, the luminescence light image 620c including the deep blood vessel image 626d that is not included in the visible light images 620a, 620b, and 620d obtained by the visible light can be obtained.

  The output unit 180 generates a composite image obtained by combining the luminescent light image 620c and the visible light image 620b or the visible light image 620d captured at a timing near the timing at which the luminescent light image 620c is captured. May be output. For example, the output unit 180 may display a composite image. The output unit 180 may record the luminescence light image 620c in association with the visible light image 620b or the visible light image 620d.

  In addition, at the timing of capturing a visible light image, the control unit 105 cuts light in the wavelength region of the excitation light and the wavelength region of the luminescence light out of the light from the light emitting unit 410 and irradiates the subject. For this reason, according to the imaging system 10, the image of the substance surface suitable for observation of the substance surface which does not include the blood vessel image inside the substance in the visible light image can be provided.

  FIG. 8 shows an example of a block configuration of the image generation unit 140. In FIG. 7, for the sake of simplicity, it is assumed that there are no factors that cause temporal changes in the image such as the movement of the distal end portion 102 of the endoscope 100 and the movement of the specimen 20. The visible light image 630c is generated by multiplexing the R signal corresponding to the amount of received light 251 and the B signal and G signal corresponding to the amounts of received light of the second light receiving element 252 and the third light receiving element 253 at the time t602, respectively. An example of the processing to be performed has been described. In this process, there may be a deviation between the R signal and other color signals in the visible light image due to the movement of the distal end portion 102 of the endoscope 100, the movement of the specimen 20, and the like.

  In this figure, the operation and function of the image generation unit 140 for correcting the influence on the visible light image due to the above-described movement and the configuration of the image generation unit 140 will be described. The image generation unit 140 includes a motion identification unit 712 and a subject image generation unit 722.

  The movement specifying unit 712 specifies the movement of the object in the image based on the image based on the B signal at a plurality of timings. Here, the movement of the object includes a movement that causes a temporal change in the image, such as a movement of the specimen 20 itself, a movement of the distal end portion 102 of the endoscope 100, and a temporal change in the zoom value of the imaging unit 110. In addition, the movement of the distal end portion 102 of the endoscope 100 is a time change in the position of the distal end portion 102 that causes a time change in the imaging position of the imaging unit 110 and a direction of the distal end portion 102 that causes a time change in the imaging direction of the imaging unit 110. Including time changes.

  Here, the movement specifying unit 712 specifies the movement of the object based on the images of the B signal at time t601 and time t602. For example, the motion specifying unit 712 may specify the motion of the object by matching the objects extracted from the plurality of images.

  The subject image generation unit 722 corrects the R signal at the timing of time t601 based on the movement, and generates an R signal to be obtained at the timing of time t602. Then, the subject image generation unit 722 multiplexes the R signal generated by the correction, the B signal at the timing of time t602, and the G signal at the timing of time t602 to generate a subject image at time t602.

  FIG. 9 is a diagram for explaining generation of a subject image whose motion is corrected. The image 821b is an R signal image from the first light receiving element 251 at time t601. The images 822b and 822c are images of the B signal from the second light receiving element 252 at time t601 and time t602, respectively. The image 823b and the image 823c are images of the G signal from the third light receiving element 253 at time t601 and time t602, respectively.

  Here, the movement specifying unit 712 specifies the movement based on the image contents of the images 822b and 822c. Specifically, the movement identifying unit 712 extracts an object indicating the same subject from the images 822b and 822c. In the example of this figure, the motion identification part 712 extracts the object 852b and the object 852c from the image 822b and the image 822c, respectively.

  The movement specifying unit 712 calculates the difference between the positions of the object 852b and the object 852c. In the example of this figure, for the sake of simplicity, it is assumed that the difference in the position occurs in the y direction on the image. The motion specifying unit 712 calculates the position difference Δy1 between the position of the object 852b and the position of the object 852c. calculate.

  The subject image generation unit 722 generates the image 821c by shifting the image 821b in the y direction by an amount corresponding to the calculated positional difference Δy1. The subject image generation unit 722 generates the subject image 830c by combining the image 821c, the image 822c, and the image 823c. Note that the composition here includes a process of multiplexing the R signal indicating the image 821c, the B signal indicating the image 822c, and the G signal indicating the image 823c with a predetermined weight.

  In the above description, the case where the motion is specified using the B signal image 822 has been described. Similarly, the motion can be specified using the G signal image 823. Which wavelength image is used by the motion specifying unit 712 to specify the motion may be determined based on the contrast of the captured image. For example, the motion identifying unit 712 may identify motion by using an image with higher contrast more preferentially. When an image of a fine structure can be used as an object for motion identification, such as when the image of the fine structure of the surface is clear, the motion may be more accurately identified using the B signal image. is there. In addition, if the image of the concavo-convex structure can be used as an object for motion identification, such as when the image of the larger concavo-convex structure on the surface is clear, the motion can be more accurately identified using the G signal image. May be possible.

  In addition, the subject image generation unit 722 may vary the amount of motion correction for the image of the R signal for each image region. For example, if the imaging direction of the imaging unit 110 is perpendicular to the subject surface and the distal end portion 102 of the endoscope 100 is moved horizontally to the subject surface, the amount of movement of the object is considered to be equal in any image region. Can do. On the other hand, for example, when the imaging direction of the imaging unit 110 is not perpendicular to the subject surface, the amount of motion in the image region in which the region far from the tip 102 is imaged is greater than that in the image region in which the region near the tip 102 is imaged. The amount of movement may be small.

  In order for the subject image generation unit 722 to calculate the motion correction amount for the image of the R signal for each image region, if the positional relationship between the subject surface and the imaging unit 110 is known or can be estimated, the positional relationship and the image Based on the position of the region, the motion correction amount can be calculated. Note that the subject image generation unit 722 controls the endoscope 100 that causes temporal changes in the image, such as a control value for controlling the position / orientation of the distal end portion 102 and a control value for controlling the zoom value of the imaging unit 110. And the amount of motion correction for the image of the R signal may be calculated based on the control value.

  In addition, the movement specifying unit 712 may calculate the movement of the object for each image area. The subject image generation unit 722 may calculate a motion correction amount for the image of each image region based on the motion of the object for each image region.

  In addition, when specifying the motion for each image region, the motion specifying unit 712 may determine for each image region which image of which wavelength is used to specify the motion. For example, the motion identifying unit 712 calculates the contrast of each image for each image region. Then, for each image region, the motion specifying unit 712 selects an image with a wavelength for which a greater contrast has been calculated in preference to an image with another wavelength, and specifies the motion of the object using the selected plurality of images. You can do it.

  As described above with reference to FIGS. 8 and 9, the movement identifying unit 712 performs the image by the light in the second wavelength region received by the second light receiving element 252 at the first timing, and the second timing. The movement of the object on the image between the first timing and the second timing is specified based on the image of the light in the second wavelength region received by the plurality of second light receiving elements 252. Then, the subject image generation unit 722 receives light in the first wavelength region received by the first light receiving element 251 at the first timing, light in the second wavelength region received by the second light receiving element 252 at the second timing, and A subject image at the second timing is generated based on the movement.

  FIG. 10 is a diagram for explaining another example of generation of a subject image with corrected motion. In the example described in this figure, the motion identifying unit 712 identifies an object motion using the R signal image 921a obtained at time t600 and the R signal image 921b obtained at time t601. To do. Similar to the method described with reference to FIG. 9, the motion identifying unit 712 extracts an object indicating the same subject from the image 921 a and the image 921 b. In the example of this figure, the movement identification part 712 extracts the object 951a and the object 951b from the image 921a and the image 921b, respectively.

  Then, the movement specifying unit 712 calculates the difference between the positions of the object 951a and the object 951b. Also in the example of this figure, assuming that the positional difference is generated in the y direction on the image for the sake of simplicity, the motion identifying unit 712 calculates the positional difference Δy2 between the position of the object 951a and the position of the object 951b. . Similar to the method described with reference to FIG. 9, the subject image generation unit 722 generates the image 921c by shifting the image 921b in the y direction by an amount corresponding to the calculated positional difference Δy2.

  In the above description, the motion is specified using the image 921a and the image 921b. However, the motion specifying unit 712 may specify the motion using the image 921b and the image of the R signal obtained at time t603. . As described above, the motion specifying unit 712 specifies the motion from the images obtained at a plurality of timings including the timings before and after the time t601 that is the target time for generating the image of the R signal whose motion is corrected. It's okay. In the case where it is acceptable to delay the display of the visible light image to some extent, it may be possible to further increase the motion identification accuracy by using an image at a later timing.

  As described above with reference to FIG. 10, the motion specifying unit 712 includes a plurality of light beams in the first wavelength region received by the first light receiving element 251 at a plurality of timings other than the second timing including the first timing. Based on the image, the movement of the object on the image during a plurality of timings is specified. Then, the subject image generation unit 722 receives light in the first wavelength region received by the first light receiving element 251 at the first timing, light in the second wavelength region received by the second light receiving element 252 at the second timing, and A subject image at the second timing is generated based on the movement.

  9 and 10, as an example of the movement specifying process, the process in which the movement specifying unit 712 uses the image captured at the timing of 2 to specify the movement has been described. The movement may be specified using images captured at three or more timings. In addition to the B signal image and the G signal image, the motion specifying unit 712 can further select an image for specifying the motion for each image area from the R signal image.

  FIG. 11 shows an example of a spectrum of light irradiated on the subject. A line 1010 indicates a spectrum of substantially white light emitted at the first timing such as the timings t600, t601, and t603 described with reference to FIG.

  On the other hand, a line 1020 indicates the spectrum of light emitted at the second timing such as time t601 described in FIG. As indicated by the spectrum, the irradiation light having substantially the spectral intensity in the first wavelength region may be irradiated also at the second timing. At the first timing and the second timing, the spectrum of the irradiation light is different in a specific wavelength region that is a wavelength region of the excitation light. As shown in the figure, the light irradiation unit 150 emits light that can increase the ratio of the spectral intensity in the specific wavelength region to the spectral intensity in the first wavelength region at the second timing than at the first timing. It's okay. More specifically, the light irradiation unit 150 emits light whose spectral intensity in the first wavelength region is larger than the spectral intensity in the specific wavelength region at the first timing, and in the specific wavelength region at the second timing. You may irradiate the light whose spectral intensity becomes larger than the spectral intensity of the 1st wavelength range.

  Although the embodiment in which the irradiation light cut filter unit 520 cuts the light in the first wavelength region has been described with reference to FIGS. 4 and 5 and the like, the irradiation light cut filter unit 520 transmits the light in the first wavelength region. It is not necessary to cut completely. Even if light having spectral intensity is irradiated to the first wavelength region at the second timing, if the irradiation light has sufficient spectral intensity in the specific wavelength region so that a luminescence image can be clearly obtained. The image of the specific wavelength region can be substantially obtained at the second timing.

  As described above with reference to FIG. 11, the control unit 105 controls the spectrum of light received by the first light receiving element. Specifically, at the first timing, the control unit causes the first light receiving element 251 to receive light in the wavelength region including the first wavelength region from the subject, and the second light receiving element 252 to receive light in the second wavelength region. To receive light. Then, at the second timing, the control unit 105 causes the first light receiving element 251 to receive light in the wavelength region including the specific wavelength region from the subject, and receives light in the second wavelength region to the second light receiving element 252. Let Here, the light in the wavelength region including the first wavelength region from the subject may be light mainly including light in the first wavelength region. The light in the wavelength region including the specific wavelength region from the subject may be light mainly including light in the specific wavelength region.

  4 and 5 and the like, as the operation of the light irradiation unit 150, the operation of temporally controlling the spectrum of the irradiation light by rotating the light source side filter unit 420 with the light from the light emitting unit 410. explained. As another example of the light irradiation unit 150, the light irradiation unit 150 may not include the light source side filter unit 420. Specifically, the light emitting unit 410 may include a plurality of light emitting elements that respectively emit light having different spectra. And the control part 105 may control the spectrum of the light irradiated to the to-be-photographed object in a 1st timing and a 2nd timing by controlling each light emission intensity | strength of a several light emitting element.

  For example, the light emitting unit 410 includes a light emitting element that emits light in a red wavelength region, a light emitting element that emits light in a blue wavelength region, a light emitting element that emits light in a green wavelength region, and a wavelength region of excitation light. A light emitting element that emits light may be included. Examples of light emitting elements that emit light in the visible light region include semiconductor elements such as LEDs. Moreover, as a light emitting element which emits excitation light, semiconductor elements, such as a semiconductor laser, can be illustrated. The light emitting element may be a phosphor that emits luminescence light such as fluorescence when excited.

  The control unit 105 can control the spectrum of light emitted to the subject by controlling the emission intensity of each of the plurality of light emitting elements at each timing. Note that “controlling the light emission intensity of each of the plurality of light emitting elements” includes controlling the combination of the light emitting elements to emit light at each timing. The light-emitting element may include a filter that transmits light in a specific wavelength region and a light emitter. If the spectrum of the light after the illuminant emits light and passes through the filter is different, these light-emitting elements can be regarded as a plurality of light-emitting elements that respectively emit light having different spectra in the present invention.

  Note that the light emitting element may be provided at the distal end portion 102 of the endoscope 100. Note that the light emitting element may be a light emitting element that emits light by electrical excitation or a light emitting element that emits light by optical excitation. When the light emitting element is a light emitting element that emits light by light excitation, the light irradiation unit 150 includes an excitation unit that emits excitation light for exciting the light emitting element, and the light emitting element. Here, the light-emitting element may emit light having a different spectrum depending on the wavelength of the excitation light. In this case, the control unit 105 can control the spectrum of the irradiation light by controlling the wavelength of the excitation light emitted from the light emitting unit at each timing. Further, the spectrum of light emitted from each light emitting element by the excitation light may be different among the plurality of light emitting elements. Further, the light that has passed through the light emitting element among the excitation light may be irradiated to the subject as irradiation light.

  As described above with reference to FIGS. 1 to 11, in the imaging device 210, the second light receiving element 252 that receives light in the blue wavelength region and the third light receiving element 253 that receives light in the green wavelength region. Are arranged at a higher density than the first light receiving elements 251. In the above description, the density of each light receiving element is defined according to the spectral intensity of the wavelength region received by each light receiving element, but the density of each light receiving element is the depth of light received by each light receiving element to the subject. It may be defined according to the achievement.

  In the following, differences between the embodiment in which the density of each light receiving element is defined in accordance with the depth of light reaching the subject and the above embodiment described with reference to FIGS. 1 to 11 will be described. Other points are the same as the above-described embodiment described in relation to FIGS. For example, the first light receiving element 251 receives light in the red wavelength region, the second light receiving element 252 receives light in the blue wavelength region, and the third light receiving element 253 receives light in the green wavelength region. FIG. 1 to FIG. 11 show the points where each light receiving element receives reflected light from a living body such as a human body containing blood components, and the functions and operations of each component of the imaging system 10 such as the image generation unit 140. This is the same as the above-described embodiment. The same points as those in the above embodiment will be omitted in the following description.

  The light in the red wavelength region received by the first light receiving element 251 and the light in the green wavelength region received by the third light receiving element 253 are compared to the light in the blue wavelength region received by the second light receiving element 252. The depth of light to the living body is large. Therefore, the first light receiving element 251 and the third light receiving element 253 receive light reflected or scattered at a deeper position in the living body than the second light receiving element 252. For this reason, the second light receiving element 252 can receive light that more reflects the fine structure of the subject surface than the light received by the first light receiving element 251 and the third light receiving element 253.

  Therefore, in this embodiment, the number of second light receiving elements 252 that receive light in a wavelength region that has a smaller depth of penetration to the subject than the light in the first wavelength region is made larger than the number of first light receiving elements 251. Thereby, it is possible to provide an image in which the fine structure of the living body surface is projected.

  Specifically, the ratio of the number of the second light receiving elements 252 to the number of the first light receiving elements 251 depends on the ratio of the depth of light in the first wavelength region to the depth of light in the second wavelength region. May be defined. More specifically, the ratio of the number of the second light receiving elements 252 to the number of the first light receiving elements 251 is substantially equal to the ratio of the depth of light in the first wavelength region to the depth of light in the second wavelength region. May be identical.

  In addition, the third light receiving element 253 receives light in the third wavelength region whose depth of penetration to the subject is smaller than the light in the first wavelength region, but the number of the third light receiving elements 253 with respect to the number of the first light receiving elements 251. May be determined according to the ratio of the depth of light in the first wavelength region to the depth of light in the third wavelength region. The ratio of the number of second light receiving elements 252 to the number of third light receiving elements 253 is determined according to the ratio of the depth of light in the second wavelength region to the depth of light in the third wavelength region. Also good.

  For example, in the imaging system 10 as an endoscope system for observing a living body, it is desirable that the density of the second light receiving elements 252 is higher than the density of the third light receiving elements 253. Furthermore, it is desirable that the density of the third light receiving elements 253 is higher than the density of the first light receiving elements 251. As described above, in this embodiment, the light receiving elements are arranged at a density corresponding to the resolving power of the image obtained by the light received by the light receiving elements.

  If the imaging system 10 described above is applied to an actual system, for example, when a doctor performs an operation or the like while viewing an image displayed by the output unit 180, the doctor recognizes an internal blood vessel that cannot be visually recognized by surface observation. May be possible. In addition, the doctor can obtain an advantage of performing an operation or the like while referring to a visible light image that is substantially free of frames.

  As mentioned above, although this invention was demonstrated using embodiment, the technical scope of this invention is not limited to the range as described in the said embodiment. It will be apparent to those skilled in the art that various modifications or improvements can be added to the above-described embodiment. It is apparent from the scope of the claims that the embodiments added with such changes or improvements can be included in the technical scope of the present invention.

1 is a diagram illustrating an example of a configuration of an imaging system 10 according to an embodiment together with a sample 20. FIG. 2 is a diagram illustrating an example of a configuration of an imaging unit 110. FIG. 6 is a diagram illustrating an example of spectral sensitivity characteristics of a first light receiving element, a second light receiving element, and a third light receiving element. FIG. 2 is a diagram illustrating an example of a configuration of a light irradiation unit 150. FIG. 5 is a diagram illustrating an example of a configuration of a light source side filter unit 420. FIG. It is a figure which shows an example of the spectral intensity of the light irradiated from the light irradiation part 150, and the spectral reflectance of a to-be-photographed object. 3 is a diagram illustrating an example of an imaging timing by an imaging unit 110 and an image generated by an image generation unit 140. FIG. 3 is a diagram illustrating an example of a block configuration of an image generation unit 140. FIG. It is a figure explaining the production | generation of the to-be-photographed object image by which the motion was correct | amended. It is a figure explaining the other example of the production | generation of the to-be-photographed object image by which the motion was correct | amended. It is a figure which shows an example of the spectrum of the light irradiated to a to-be-photographed object.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Imaging system 20 Specimen 100 Endoscope 102 Front-end | tip part 105 Control part 110 Imaging part 112 Lens 120 Light guide 124 Output port 130 Forceps port 135 Forceps 138 Nozzle 140 Image generation part 150 Light irradiation part 160 Imaging control part 170 Light emission control part 180 Output unit 190 ICG injection unit 210 Imaging device 220 Spectral filter unit 230 Light receiving side excitation light cut filter unit 251 First light receiving element 252 Second light receiving element 253 Third light receiving elements 330, 310, 320 Line 410 Light emitting unit 420 Light source side filter unit 510 Excitation light cut filter unit 520 Irradiation light cut filter unit 712 Motion identification unit 722 Subject image generation unit

Claims (23)

An imaging system comprising an imaging device,
The imaging device is:
A first light receiving element that receives light in the first wavelength region;
A second light receiving element that receives light in a wavelength region having a smaller depth of penetration to the subject than the light in the first wavelength region;
The imaging system in which the number of the second light receiving elements is larger than the number of the first light receiving elements. The ratio of the number of the second light receiving elements to the number of the first light receiving elements is the ratio of the light in the first wavelength region to the depth of light in the second wavelength region that is the wavelength region received by the second light receiving element. The imaging system according to claim 1, which is determined according to a ratio of depth of penetration. The ratio of the number of the second light receiving elements to the number of the first light receiving elements is substantially the same as the ratio of the light penetration of the first wavelength region to the light penetration of the second wavelength region. Item 3. The imaging system according to Item 2. The first light receiving element and the second light receiving element receive reflected light from a living body,
The imaging system according to claim 1, wherein the second light receiving element receives light in a blue wavelength region, and the first light receiving element receives light in a red wavelength region. The first light receiving element and the second light receiving element receive reflected light from a human body,
The imaging system according to claim 4, wherein the second light receiving element receives light in a blue wavelength region, and the first light receiving element receives light in a red wavelength region. The first light receiving element and the second light receiving element receive reflected light from a living body,
4. The imaging system according to claim 1, wherein the second light receiving element receives light in a green wavelength region, and the first light receiving element receives light in a red wavelength region. 5. The imaging system according to claim 4, wherein the first light receiving element and the second light receiving element receive reflected light from a human body including blood components. The imaging system according to claim 5 or 7, further comprising an image generation unit configured to generate an image of a human body based on the amount of light received by the first light receiving element and the second light receiving element. The imaging device is light in a third wavelength region that is different from the first wavelength region and the second wavelength region and has a smaller depth of penetration to the subject than the light in the first wavelength region. A third light receiving element for receiving
The ratio of the number of the third light receiving elements to the number of the first light receiving elements is determined according to a ratio of the light penetration of the first wavelength region to the light penetration of the third wavelength region. Item 4. The imaging system according to Item 3. A first light receiving element that receives light in the first wavelength region;
A second light receiving element that receives light in a wavelength region having a smaller depth of penetration to the subject than the light in the first wavelength region;
The number of the second light receiving elements is an imaging device greater than the number of the first light receiving elements. An imaging system comprising an imaging device,
The imaging device is:
A first light receiving element that receives light in the first wavelength region;
A second light receiving element for receiving light in a wavelength region having a spectral intensity smaller than that in the first wavelength region;
The imaging system in which the number of the second light receiving elements is larger than the number of the first light receiving elements. The imaging system according to claim 11, wherein the second light receiving element receives light in a second wavelength region that is a wavelength region having a spectral reflectance smaller than a spectral reflectance of a subject in the first wavelength region. The ratio of the number of the second light receiving elements to the number of the first light receiving elements is determined according to a ratio of the spectral reflectance in the first wavelength region to the spectral reflectance in the second wavelength region. Imaging system. The ratio of the number of the second light receiving elements to the number of the first light receiving elements is substantially the same as the ratio of the spectral reflectance in the first wavelength region to the spectral reflectance in the second wavelength region. Imaging system. A light irradiator that irradiates the subject with light;
The ratio of the number of the second light receiving elements to the number of the first light receiving elements is the first of the product of the spectral reflectance in the second wavelength region and the spectral intensity of the light irradiated to the subject by the light irradiation unit. The imaging system according to claim 14, wherein the imaging system is substantially the same as a product ratio of a spectral reflectance in a wavelength region and a spectral intensity of light irradiated on the subject by the light irradiation unit. The ratio of the number of the second light receiving elements to the number of the first light receiving elements is the spectral reflectance in the second wavelength region, the spectral intensity of the light irradiated to the subject by the light irradiation unit, and the second light receiving elements. Is substantially the same as the ratio of the product of the spectral reflectance in the first wavelength region, the spectral intensity of the light irradiated to the subject by the light irradiation unit, and the light reception sensitivity of the first light receiving element. The imaging system according to claim 15. The first light receiving element and the second light receiving element receive reflected light from a living body,
The imaging system according to claim 11, wherein the second light receiving element receives light in a blue wavelength region, and the first light receiving element receives light in a red wavelength region. The first light receiving element and the second light receiving element receive reflected light from a human body,
The imaging system according to claim 17, wherein the second light receiving element receives light in a blue wavelength region, and the first light receiving element receives light in a red wavelength region. The first light receiving element and the second light receiving element receive reflected light from a living body,
The imaging system according to claim 11, wherein the second light receiving element receives light in a green wavelength region, and the first light receiving element receives light in a red wavelength region. The imaging system according to claim 17, wherein the first light receiving element and the second light receiving element receive reflected light from a human body including blood components. 21. The imaging system according to claim 18 or 20, further comprising an image generation unit that generates an image of a human body based on the amount of light received by the first light receiving element and the second light receiving element. The imaging device receives light in a third wavelength region, which is different from the first wavelength region and the second wavelength region, and has a spectral intensity smaller than a spectral intensity in the first wavelength region. A third light receiving element
The ratio of the number of the third light receiving elements to the number of the first light receiving elements is determined according to a ratio of the spectral reflectance in the first wavelength region to the spectral reflectance of the subject in the third wavelength region. The imaging system described in 1. A first light receiving element that receives light in the first wavelength region;
A second light receiving element that receives light in a wavelength region having a spectral intensity smaller than that in the first wavelength region,
The number of the second light receiving elements is an imaging device greater than the number of the first light receiving elements.

Images