JP2015173737A - biological observation system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a biological observation system capable of improving efficiency in performing a surgical treatment for a lesioned part.SOLUTION: A biological observation system 101 includes: an illumination part for generating first illumination light whose absorption coefficient changes according to a degree of hemoglobin oxygen saturation in the blood in a predetermined wavelength band, second illumination light including a wavelength in which an absorption coefficient of oxyhemoglobin is equal to an absorption coefficient of deoxyhemoglobin in the predetermined wavelength, and third illumination light having one or more wavelength bands in a wavelength band longer than the predetermined wavelength band; an image pickup part 12; an information acquisition part for acquiring the information related to a degree of oxygen saturation of a subject in the predetermined wavelength band by an inter-image computation of an image signal at a time when the first illumination light is radiated and an image signal at a time when the second illumination light is radiated; and an image information generation part for generating image information that reflects the information related to the degree of oxygen saturation of the subject in the predetermined wavelength band.

Description

  The present invention relates to a living body observation system, and more particularly to a living body observation system used for observation of living tissue.

  As a technique related to endoscopic observation in the medical field, for example, a subject including a biological mucous membrane is irradiated with narrowband light having a predetermined wavelength band, and the return light from the subject irradiated with the narrowband light is used. Blood vessel information for enabling identification of a normal site and a lesion site included in the subject based on an image or a signal obtained by imaging the return light, and the acquired blood vessel information A technique for presenting visual information generated based on the information to an operator is conventionally known.

  Specifically, for example, Patent Document 1 discloses a first narrowband light set in a wavelength band of 440 ± 10 nm, a second narrowband light set in a wavelength band of 470 ± 10 nm, and 400 The subject tissue is sequentially irradiated with the third narrowband light set in the wavelength band of ± 10 nm, the subject tissue that is sequentially irradiated with the first to third narrowband light is imaged by the imaging device, and the subject A technique is disclosed in which blood vessel information such as oxygen saturation information is acquired based on three types of imaging signals obtained by imaging a tissue, and an image generated based on the acquired blood vessel information is displayed on a monitor. ing.

  By the way, in the case of a surgical treatment under endoscopic observation, the middle surface to the distant view observation in which the distal end surface of the elongated insertion portion inserted into the body cavity is observed away from the surface of the subject (for example, 10 mm or more), After specifying the approximate position of the lesion site included in the subject, the lesion site is treated by close-up magnification observation in which the distal end surface is observed close to the surface of the subject (for example, up to 4 mm or less). Such a procedure is performed.

  However, Patent Document 1 does not particularly disclose a technique for changing information to be presented to the surgeon according to the observation distance at the time of endoscopic observation in consideration of the above-described technique. As a result, according to the configuration disclosed in Patent Document 1, for example, information regarding an observation target that is different from the operator's desired observation target may be displayed on the monitor. As a result, there is a problem that the efficiency of performing a surgical procedure is reduced.

  The present invention has been made in view of the above-described circumstances, and an object of the present invention is to provide a living body observation system capable of improving the efficiency when a surgical treatment is performed on a lesion site.

  The living body observation system of one embodiment of the present invention includes a first illumination light whose extinction coefficient changes in accordance with oxygen saturation of blood hemoglobin in a predetermined wavelength band, and an absorption coefficient of oxyhemoglobin in the predetermined wavelength band. A second illumination light including a first isosbestic point wavelength which is a wavelength at which the absorption coefficient of deoxyhemoglobin becomes equal; and a first wavelength band having one or more wavelength bands in a wavelength band longer than the predetermined wavelength band. An illumination unit configured to generate the illumination light, an imaging unit configured to image the return light from the subject irradiated with the illumination light emitted from the illumination unit, and predetermined observation In the state, the image signal of the subject when the first illumination light is irradiated and the image signal of the subject when the second illumination light is irradiated to the predetermined wavelength band by the inter-image calculation Oh An information acquisition unit configured to acquire information on oxygen saturation of the subject, and generating image information reflecting information on oxygen saturation of the subject in the predetermined wavelength band in the predetermined observation state And an image configured to generate image information based on an image signal of the subject when the third illumination light is irradiated when observing the subject in an enlarged manner from the predetermined observation state. An information generation unit.

  According to the living body observation system of the present invention, it is possible to improve the efficiency when a surgical treatment is performed on a lesion site.

The figure which shows the structure of the principal part of the biological observation system which concerns on a 1st Example. FIG. 6 is a diagram illustrating an example of spectral characteristics of a primary color filter. The figure for demonstrating an example of the wavelength of the light emitted from a light source device at the time of special light observation mode in 1st Example. The figure for demonstrating the specific example of the wavelength band of NB1 light emitted from a light source device at the time of special light observation mode in 1st Example. The figure for demonstrating the specific example of the wavelength band of NR1 light emitted from a light source device at the time of special light observation mode in 1st Example. The figure for demonstrating an example of the luminance value of the pixel contained in the observation image produced | generated at the time of 1st display mode in 1st Example. The figure for demonstrating an example of the luminance value of the pixel different from FIG. 6 contained in the observation image produced | generated at the time of 1st display mode in 1st Example. The figure for demonstrating an example of the luminance value of the pixel contained in the observation image produced | generated at the time of a 2nd display mode in 1st Example. The figure for demonstrating an example of the luminance value of the pixel different from FIG. 8 contained in the observation image produced | generated at the time of a 2nd display mode in 1st Example. The figure which shows the structure of the principal part of the biological observation system which concerns on a 2nd Example. The figure for demonstrating an example of the wavelength of the light emitted from a light source device at the time of special light observation mode in 2nd Example. The figure for demonstrating an example of the luminance value of the pixel contained in the observation image produced | generated at the time of 1st display mode in 2nd Example. The figure for demonstrating an example of the luminance value of the pixel different from FIG. 12 contained in the observation image produced | generated at the time of 1st display mode in 2nd Example. The figure for demonstrating an example of the luminance value of the pixel contained in the observation image produced | generated at the time of a 2nd display mode in 2nd Example. The figure for demonstrating an example of the luminance value of the pixel different from FIG. 14 contained in the observation image produced | generated at the time of a 2nd display mode in 2nd Example.

  Embodiments of the present invention will be described below with reference to the drawings.

(First embodiment)
1 to 9 relate to a first embodiment of the present invention. FIG. 1 is a diagram illustrating a configuration of a main part of the living body observation system according to the first embodiment.

  As shown in FIG. 1, the living body observation system 101 includes an elongated insertion portion that can be inserted into a subject that is a living body, and also captures an imaging signal by imaging a subject such as a living tissue in the subject. An output endoscope 1, a light source device 2 that supplies light used for observing the subject via a light guide 6 inserted and disposed inside the endoscope 1, and an image output from the endoscope 1 A processor 3 that generates and outputs an observation image according to a signal, a display device 4 that displays an observation image and the like output from the processor 3, and an instruction according to a user input operation are given to the processor 3. And an input device 5 having a switch and / or a button capable of being configured.

  The endoscope 1 images an illumination optical system 11 that irradiates the subject with light transmitted by the light guide 6 and reflected light (return light) emitted from the subject in accordance with the light emitted from the illumination optical system 11. The imaging unit 12 that outputs the obtained imaging signal is provided at the distal end of the insertion unit. The endoscope 1 includes a scope switch 13 that can give various instructions to the processor 3 in accordance with user operations.

  The imaging unit 12 is configured to capture reflected light (return light) from a subject illuminated by illumination light emitted from the light source device 2 and output an imaging signal. Specifically, the imaging unit 12 matches the imaging surface of the objective optical system 12a with an objective optical system 12a that forms an image of reflected light (returned light) emitted from the subject and a primary color filter 121. The image pickup device 12b is arranged.

  The image pickup device 12b includes, for example, a CCD and is driven according to the image pickup device drive signal output from the processor 3, and images reflected light (return light) from the subject imaged on the image pickup surface. The obtained imaging signal is output.

  The primary color filter 121 has a spectral sensitivity as illustrated in FIG. 2 in each wavelength band of the red color range, the green color range, and the blue color range. FIG. 2 is a diagram illustrating an example of spectral characteristics of the primary color filter.

  That is, the imaging unit 12 according to the present exemplary embodiment captures a subject illuminated with NR1 light (described later) and a subject illuminated with NR2 light (described later) with a pixel group having sensitivity in a red region, and NB1 light (described later). The illuminating object and the illuminating object illuminated by NB2 light (described later) are imaged by a pixel group having sensitivity in the blue region.

  The scope switch 13 includes an observation mode switch 13a and a display mode switch 13b.

  The observation mode change-over switch 13a instructs the processor 3 to set (switch) the observation mode of the living body observation system 101 to either the white light observation mode or the special light observation mode in accordance with a user operation. It is configured to be able to.

  The display mode change-over switch 13b sets the display mode of the observation image displayed on the display device 4 to either the first display mode or the second display mode in the special light observation mode according to the user's operation. This instruction can be given to the processor 3.

  The light source device 2 includes an illumination control unit 21 and a light emitting unit 22 including a white light generation unit 22a and a special light generation unit 22b.

  The illumination control unit 21 includes, for example, a control circuit and the like. In addition, when the illumination control unit 21 detects that the observation mode of the living body observation system 101 is set to the white light observation mode based on the system control signal output from the processor 3, for example, the white light generation unit It is configured to generate white light from 22 a and generate an illumination control signal for quenching the special light generator 22 b and output the generated illumination control signal to the light emitting unit 22.

  For example, when the illumination control unit 21 detects that the observation mode of the living body observation system 101 is set to the special light observation mode based on the system control signal output from the processor 3, the illumination control unit 21 sets the white light generation unit 22a. In addition to extinction, the special light generator 22b generates an illumination control signal for generating NB1 light, NB2 light, NR1 light, and NR2 light, which will be described later, in a predetermined order, and sends the generated illumination control signal to the light emitting unit 22. It is configured to output.

  The white light generation unit 22a includes, for example, one or more LEDs (light emitting diodes), and is white light that is broadband light including a red region, a green region, and a blue region based on an illumination control signal output from the illumination control unit 21. It is comprised so that light can be generated.

  The special light generator 22b includes, for example, a plurality of LEDs or LDs (laser diodes), and is configured to have different wavelength bands based on the illumination control signal output from the illumination controller 21. Light, NB2 light, NR1 light, and NR2 light can be generated individually or simultaneously. FIG. 3 is a diagram for explaining an example of the wavelength of light emitted from the light source device in the special light observation mode in the first embodiment. FIG. 4 is a diagram for explaining a specific example of the wavelength band of the NB1 light emitted from the light source device in the special light observation mode in the first embodiment. FIG. 5 is a diagram for explaining a specific example of the wavelength band of the NR1 light emitted from the light source device in the special light observation mode in the first embodiment.

  For example, as shown in FIG. 3 and FIG. 4, the NB1 light has a wavelength at which the absorption coefficient of oxyhemoglobin and the absorption coefficient of reduced hemoglobin are equal, that is, the isosbestic point wavelengths of oxyhemoglobin and reduced hemoglobin as a peak wavelength λP1. It is set to have.

  The wavelength band of the NB1 light is, for example, as shown in FIGS. 3 and 4, a line segment Lb1 indicating a wavelength λb1 shorter than the peak wavelength λP1, a line segment LH1 indicating an absorption spectrum of oxyhemoglobin, and absorption of reduced hemoglobin. The area of the region Sb1 surrounded by the three line segments of the line segment LH2 indicating the spectrum, and the region surrounded by the three line segments of the line segment Lb2, the line segment LH1, and the line segment LH2 indicating the wavelength λb2 longer than the peak wavelength λP1 The wavelength band is set such that the area of Sb2 is substantially equal. Further, the wavelength band of the NB1 light is set on the shorter wavelength side than the wavelength band of the NB2 light.

  That is, the wavelength band of NB1 light includes the isosbestic point wavelengths of oxyhemoglobin and reduced hemoglobin in the visible range (blue range) and is set so as not to overlap with the wavelength band of NB2 light.

  In the present embodiment, preferably, the peak wavelength λP1 is set as 422 nm, the wavelength λb1 is set as 408 nm, and the wavelength λb2 is set as 432 nm.

  For example, as shown in FIG. 3, the NB2 light is set to have a peak wavelength λP2 having a wavelength at which the absorption coefficient of oxyhemoglobin is larger than the absorption coefficient of reduced hemoglobin.

  Further, for example, as shown in FIG. 3, the wavelength band of NB2 light does not overlap with the wavelength band of NB1 light in the blue region, and the absorption coefficient of oxyhemoglobin is always larger than the absorption coefficient of deoxyhemoglobin. It is set as such a wavelength band.

  That is, the wavelength band of NB2 light is set as a wavelength band in which the absorption coefficient changes in the visible region (blue region) according to the oxygen saturation of blood hemoglobin.

  In the present embodiment, the peak wavelength λP2 is preferably set to a predetermined wavelength of 460 nm to 470 nm.

  For example, as shown in FIGS. 3 and 5, the NR1 light has a wavelength at which the absorption coefficient of oxidized hemoglobin and the absorption coefficient of reduced hemoglobin are equal on the longer wavelength side than λP1, that is, oxidation on the longer wavelength side than λP1. It is set so that the isosbestic point wavelengths of hemoglobin and reduced hemoglobin are provided as the peak wavelength λP3.

  Further, for example, as shown in FIGS. 3 and 5, the wavelength band of the NR1 light is surrounded by three line segments of a line segment Lr1, a line segment LH1, and a line segment LH2 indicating a wavelength λr1 shorter than the peak wavelength λP3. A wavelength band in which the area of the region Sr1 and the area of the region Sr2 surrounded by the three line segments Lr2, line segment LH1, and line segment LH2 indicating the wavelength λr2 longer than the peak wavelength λP3 are substantially equal. Is set. Further, the wavelength band of the NR1 light is set on the shorter wavelength side than the wavelength band of the NR2 light.

  That is, the wavelength band of NR1 light includes the isosbestic point wavelengths of oxyhemoglobin and reduced hemoglobin in the visible range (yellow range) and is set so as not to overlap with the wavelength band of NR2 light.

  In the present embodiment, preferably, the peak wavelength λP3 is set as 584 nm, the wavelength λr1 is set as 576 nm, and the wavelength λr2 is set as 592 nm.

  For example, as shown in FIG. 3, the NR2 light is set to have a peak wavelength λP4 having a wavelength at which the absorption coefficient of reduced hemoglobin is larger than the absorption coefficient of oxyhemoglobin.

  Further, for example, as shown in FIG. 3, the wavelength band of NB2 light does not overlap with the wavelength band of NR1 light in the red region, and the absorption coefficient of reduced hemoglobin is always larger than that of oxyhemoglobin. It is set as such a wavelength band.

  That is, the wavelength band of NR2 light is set as a wavelength band in which the absorption coefficient changes in accordance with the oxygen saturation level of blood hemoglobin within the visible range (red range).

  In the present embodiment, the peak wavelength λP4 is preferably set to either 650 nm or a predetermined wavelength near 650 nm.

  The processor 3 includes a preprocessing unit 31, an image signal processing unit 32, an observation image generation unit 33, and a control unit 34.

  The preprocessing unit 31 includes, for example, a noise reduction circuit, an A / D conversion circuit, and the like, and performs digital processing by performing processing such as noise removal and A / D conversion on the imaging signal output from the endoscope 1. An image signal is generated, and the generated image signal is output to the image signal processing unit 32.

  The image signal processing unit 32 includes, for example, a signal processing circuit. Further, the image signal processing unit 32 performs preprocessing when detecting that the observation mode of the biological observation system 101 is set to the white light observation mode based on the system control signal output from the control unit 34, for example. The image signal output from the unit 31 is separated for each color component of R (red) component, G (green) component, and B (blue) component obtained by imaging reflected light (returned light) of white light. It is configured to output to the observation image generation unit 33.

  For example, when the image signal processing unit 32 detects that the observation mode of the living body observation system 101 is set to the special light observation mode based on the system control signal output from the control unit 34, the preprocessing unit 31. The NB1 component obtained by imaging the reflected light (returned light) of the NB1 light, the NB2 component obtained by imaging the reflected light (returned light) of the NB2 light, and the reflected light of the NR1 light ( Processing is performed to separate the NR1 component obtained by imaging the return light) and the color component of the NR2 component obtained by imaging the reflected light (return light) of the NR2 light.

  When the image signal processing unit 32 detects that the setting for displaying the observation image in the first display mode has been made based on the system control signal output from the control unit 34, for example, A coefficient C1 is calculated by performing an inter-image calculation using the NB1 component and the NB2 component of the color components separated as described above, and the calculated coefficient C1 is multiplied by the NR1 component and output to the observation image generation unit 33. It is configured as follows.

  Further, when the image signal processing unit 32 detects that the setting for displaying the observation image in the second display mode has been made based on the system control signal output from the control unit 34, for example, The coefficient C2 is calculated by performing an inter-image calculation using the NR1 component and the NR2 component among the color components separated in this way, and the calculated coefficient C2 is multiplied by the NR2 component and output to the observation image generation unit 33. It is configured as follows.

  The observation image generation unit 33 includes, for example, an image processing circuit. Further, based on the system control signal output from the control unit 34, for example, the observation image generation unit 33 detects that the observation mode of the living body observation system 101 is set to the white light observation mode. The luminance value of the R component output from the processing unit 32 is assigned to the R channel corresponding to the red color of the display device 4, and the luminance value of the G component output from the image signal processing unit 32 is set to G corresponding to the green color of the display device 4. An observation image is generated by allocating the luminance value of the B component output from the image signal processing unit 32 to the B channel corresponding to the blue color of the display device 4 and assigning the generated observation image to the display device 4. Is configured to do.

  Based on the system control signal output from the control unit 34, the observation image generation unit 33 is output from the image signal processing unit 32, for example, when the observation mode of the living body observation system 101 is set to the special light observation mode. The luminance value of the NR2 component is assigned to the R channel, the luminance value of the NR1 component output from the image signal processing unit 32 is assigned to the G channel, and the NB1 component and NB2 component output from the image signal processing unit 32 are added. An observation image is generated by assigning the luminance value obtained in this way to the B channel, and the generated observation image is output to the display device 4.

  The control unit 34 is configured to generate and output an image sensor driving signal for driving the image sensor 12b.

  The control unit 34 includes, for example, a CPU or a control circuit, generates a system control signal for performing an operation corresponding to the observation mode set in the observation mode changeover switch 13a, and generates the illumination control unit 21 and the image signal. It is configured to output to the processing unit 32 and the observation image generation unit 33.

  The control unit 34 is configured to generate a system control signal for causing the operation corresponding to the display mode set in the display mode changeover switch 13b to be output to the image signal processing unit 32. That is, the control unit 34 is configured to control the image signal processing unit 32 to switch the display mode when displaying the observation image on the display device 4 to the first display mode or the second display mode. Has been.

  Then, the effect | action of the biological observation system 101 which concerns on a present Example is demonstrated. In the following, for the sake of simplicity, description of specific operations when the observation mode of the living body observation system 101 is set to the white light observation mode is omitted. In the following, for the sake of simplicity, processing based on the NB1 image, NB2 image, NR1 image, and NR2 image corresponding to each color component obtained by separating the image signal from the preprocessing unit 31 is performed by the image signal processing unit 32. It will be described as being performed in

  The user turns on the power of each part of the living body observation system 101, sets the observation mode of the living body observation system 101 to the white light observation mode, and then confirms the observation image (white light image) displayed on the display device 4. Then, the insertion portion of the endoscope 1 is inserted into the subject.

  And a user is a position where the distance between the front-end | tip surface of the front-end | tip part of the insertion part of the endoscope 1 and the surface of the biological tissue which is a subject turns into observation distance L1 equivalent to a mid-ground to distant view observation. In the state where the distal end portion is disposed, the observation mode switching switch 13a and the display mode switching switch 13b are operated to switch the observation mode of the living body observation system 101 to the special light observation mode and to observe the first display mode. An instruction for displaying an image is given. In the present embodiment, the distal end portion of the endoscope 1 is preferably arranged at a position where the observation distance L1 is 10 mm.

  When the control unit 34 detects that the observation mode of the living body observation system 101 is set to the special light observation mode, for example, timing for simultaneously generating NB1 light and NR1 light and timing for simultaneously generating NB2 light and NR2 light. Are set at timings different from each other, then a system control signal capable of specifying each of the set timings is generated and output to the illumination control unit 21, the image signal processing unit 32, and the observation image generation unit 33. In addition, the control unit 34 generates a system control signal for performing an operation corresponding to the first display mode, and outputs the system control signal to the image signal processing unit 32. According to such control of the control unit 34, when the primary color filter 121 is provided in the imaging device 12b, the frame rate of the observation image displayed on the display device 4 in the special light observation mode is optimized. can do.

  In addition, according to the present embodiment, in the special light observation mode, as long as the imaging signals corresponding to the NB1 light, the NB2 light, the NR1 light, and the NR2 light can be obtained individually, NB1 light, NB2 light, NR1 light, and NR2 light may be generated at different timings.

  Based on the system control signal output from the control unit 34, the illumination control unit 21 performs control for generating NB1 light and NR1 light at the same time and control for generating NB2 light and NR2 light at the same time as special light. An illumination control signal for sequentially repeating the generation unit 22 b is generated, and the generated illumination control signal is output to the light emitting unit 22. Then, according to the control of the illumination control unit 21, the NB1 light and the NR1 light, the NB2 light, and the NR2 light are sequentially irradiated to the subject through the illumination optical system 11, and the reflected light (return light) from the subject. ) Is output from the image sensor 12b, and an image signal generated based on the image signal from the image sensor 12b is output from the preprocessing unit 31.

  The image signal processing unit 32 separates the image signal output from the preprocessing unit 31 into an NB1 image, an NB2 image, an NR1 image, and an NR2 image, and uses the luminance values of the separated NB1 image and NB2 image to generate an inter-image signal. By performing the calculation, a coefficient C1 corresponding to each pixel position of the NB1 image and the NB2 image is calculated.

  Specifically, the image signal processing unit 32 performs a coefficient process corresponding to each pixel position of the NB1 image and the NB2 image, for example, by performing a calculation process that removes the luminance value of the NB1 image from the luminance value of the NB2 image. C1 is calculated.

  Alternatively, the image signal processing unit 32 performs, for example, arithmetic processing such as subtracting 1 from the value obtained by dividing the luminance value of the NB2 image from the luminance value of the NB2 image, thereby obtaining each pixel of the NB1 image and the NB2 image. A coefficient C1 corresponding to the position is calculated.

  The image signal processing unit 32 outputs the NB1 image, the NB2 image, and the NR2 image obtained by separating the image signal output from the preprocessing unit 31 to the observation image generation unit 33. In addition, the image signal processing unit 32 multiplies the luminance value at the corresponding pixel position in the NR1 image by the coefficient C1 calculated for each pixel position by the above-described inter-image calculation, and outputs the result to the observation image generation unit 33.

  The observation image generation unit 33 assigns the luminance value of the NR2 image output from the image signal processing unit 32 to the R channel, assigns the luminance value of the NR1 image output from the image signal processing unit 32 to the G channel, and performs image signal processing. An observation image is generated by assigning a luminance value obtained by adding the NB1 image and the NB2 image output from the unit 32 to the B channel, and the generated observation image is output to the display device 4.

  Here, the value of the coefficient C1 calculated by the above-described calculation between images increases as the amount of reduced hemoglobin contained in the blood increases as compared with the amount of oxidized hemoglobin, and the value of the oxidized hemoglobin contained in the blood. The amount decreases as the amount increases compared to the amount of reduced hemoglobin. That is, the coefficient C1 is calculated as a relatively large value when the oxygen saturation level in the blood is low, and is calculated as a relatively small value when the oxygen saturation level in the blood is high.

  Therefore, according to the processing in the first display mode in the present embodiment, an observation image in which the green luminance value varies according to the magnitude of oxygen saturation in the blood is generated. Specifically, according to the processing in the first display mode in the present embodiment, for example, the green luminance value in a pixel having a low level of oxygen saturation in blood is relatively large (see FIG. 6). ), An observation image is generated in which the luminance value of green at a pixel having a high oxygen saturation level in the blood is relatively small (see FIG. 7). FIG. 6 is a diagram for explaining an example of luminance values of pixels included in an observation image generated in the first display mode in the first embodiment. FIG. 7 is a diagram for explaining an example of luminance values of pixels different from those in FIG. 6 included in the observation image generated in the first display mode in the first embodiment.

  As a result, in the first display mode of the present embodiment, for example, the red intensity of pixels belonging to a region where a lesion site such as a venule or cancer is present is relatively lowered, and an arteriole is present. An observation image in which the red intensity of the pixels belonging to the region is relatively increased is displayed on the display device 4. In other words, in the first display mode of the present embodiment, an observation image having a color tone that can distinguish the capillaries and lesion sites on the mucosal surface layer with the intensity of red is displayed on the display device 4.

  Note that, according to the present embodiment, for example, the coefficient C1 is not limited to being directly multiplied by the NR1 image. For example, the coefficient C1 is selected from the look-up table configured such that the output value decreases as the oxygen saturation increases. May be extracted and the NR1 image may be multiplied by the extracted output value.

  On the other hand, the user, for example, sets the distance between the distal end surface of the distal end portion of the insertion portion of the endoscope 1 and the surface of the biological tissue as the subject to an observation distance L2 (<L1) corresponding to close-up magnification observation. In a state where the tip portion is arranged at such a position, an instruction for displaying an observation image in the second display mode is performed by operating the display mode changeover switch 13b. In the present embodiment, the distal end portion of the endoscope 1 is preferably arranged at a position where the observation distance L2 is 2 to 4 mm.

  The control unit 34 generates a system control signal for performing an operation corresponding to the second display mode, and outputs the system control signal to the image signal processing unit 32.

  The image signal processing unit 32 separates the image signal output from the preprocessing unit 31 into an NB1 image, an NB2 image, an NR1 image, and an NR2 image, and uses the luminance values of the separated NR1 image and NR2 image to generate an inter-image signal. By calculating, a coefficient C2 corresponding to each pixel position of the NR1 image and the NR2 image is calculated.

  Specifically, the image signal processing unit 32 performs a coefficient process corresponding to each pixel position of the NR1 image and the NR2 image, for example, by performing a calculation process that removes the luminance value of the NR1 image from the luminance value of the NR2 image. C2 is calculated.

  Alternatively, the image signal processing unit 32 performs, for example, arithmetic processing such that 1 is subtracted from a value obtained by dividing the luminance value of the NR2 image from the luminance value of the NR2 image, whereby each pixel of the NR1 image and the NR2 image. A coefficient C2 corresponding to the position is calculated.

  The image signal processing unit 32 outputs the NB1 image, the NB2 image, and the NR1 image obtained by separating the image signal output from the preprocessing unit 31 to the observation image generation unit 33. Further, the image signal processing unit 32 multiplies the luminance value of the corresponding pixel position in the NR2 image by the coefficient C2 calculated for each pixel position by the above-described inter-image calculation, and outputs the result to the observation image generation unit 33.

  The observation image generation unit 33 assigns the luminance value of the NR2 image output from the image signal processing unit 32 to the R channel, assigns the luminance value of the NR1 image output from the image signal processing unit 32 to the G channel, and performs image signal processing. An observation image is generated by assigning a luminance value obtained by adding the NB1 image and the NB2 image output from the unit 32 to the B channel, and the generated observation image is output to the display device 4.

  Here, the value of the coefficient C2 calculated by the above-described inter-image calculation increases as the amount of oxygenated hemoglobin contained in the blood increases as compared with the amount of reduced hemoglobin, and the value of the reduced hemoglobin contained in the blood. The amount decreases as the amount of oxygenated hemoglobin increases. That is, the coefficient C2 is calculated as a relatively large value when the oxygen saturation level in the blood is high, and is calculated as a relatively small value when the oxygen saturation level in the blood is low.

  Therefore, according to the processing in the second display mode in the present embodiment, an observation image in which the red luminance value varies according to the level of oxygen saturation in the blood is generated. Specifically, according to the processing in the second display mode in the present embodiment, for example, the red luminance value in a pixel having a high oxygen saturation level in blood is relatively increased (see FIG. 8). ) And an observation image in which the red luminance value in the pixel having a low level of oxygen saturation in the blood is relatively small (see FIG. 9) is generated. FIG. 8 is a diagram for explaining an example of a luminance value of a pixel included in an observation image generated in the second display mode in the first embodiment. FIG. 9 is a diagram for explaining an example of luminance values of pixels different from those in FIG. 8 included in the observation image generated in the second display mode in the first embodiment.

  As a result, in the second display mode of the present embodiment, for example, the red intensity of the pixels belonging to the region where the thick vein is present is relatively reduced, and the pixels belonging to the region where the thick artery is present An observation image in which the intensity of red is relatively increased is displayed on the display device 4. That is, in the second display mode of the present embodiment, an observation image having a color tone capable of visually distinguishing the large-diameter artery and the large-diameter vein in the submucosa in the red to blue color gamut is displayed. It is displayed on the device 4.

  Note that, according to the present embodiment, for example, the coefficient C2 is not limited to the coefficient C2 directly multiplied by the NR2 image. For example, the coefficient C2 is selected from the look-up table configured such that the output value increases as the oxygen saturation increases. May be extracted and the NR2 image may be multiplied by the extracted one output value.

  As described above, according to the present embodiment, when the first display mode is set, the color tone that can easily visually identify the boundary between the normal site and the lesion site on the mucous membrane surface layer is provided. An observation image can be displayed on the display device 4. In addition, according to the present embodiment, when the second display mode is set, an observation image having a color tone that can visually distinguish a large vein and a large artery in the submucosal layer visually is displayed. 4 can be displayed. Therefore, according to the present Example, the efficiency at the time of performing surgical treatments, such as ESD (endoscopic submucosal dissection), etc. with respect to a lesion site | part can be improved.

  In addition, according to the present Example, it is not restricted to what has a structure which switches a 1st display mode and a 2nd display mode according to operation of the display mode switch 13b, For example, the endoscope 1 A distance measuring sensor configured to detect a distance between the distal end surface of the distal end portion of the insertion portion and the surface of the biological tissue that is the subject is provided in the insertion portion of the endoscope 1, and the distance measuring sensor Based on the detection result, a system control signal for switching the display mode for displaying the observation image on the display device 4 to the first display mode or the second display mode may be output from the control unit 34. Good.

  Further, according to the present embodiment, for example, when the second display mode is set, the luminance value of the NR2 image is multiplied by the coefficient C2 and output to the observation image generation unit 33, and the NB1 image and the NB2 image are also output. A process of multiplying the luminance value by the coefficient C2 and outputting the result to the observation image generation unit 33 may be performed. According to such processing, the observation image displayed on the display device 4 when the first display mode is set, and the display device 4 displayed when the second display mode is set. The color tone of the lesion site can be made substantially the same in the observation image.

  Further, according to the present embodiment, the processing for causing the display device 4 to simultaneously display the observation image generated in the first display mode and the observation image generated in the second display mode is performed. It may be.

  On the other hand, according to the present embodiment, instead of the NB2 light as described above, for example, the peak wavelength λP2 includes 440 nm, which is a wavelength at which the absorption coefficient of reduced hemoglobin is larger than the absorption coefficient of oxidized hemoglobin, A modification in which NB2 light having a wavelength band in which the absorption coefficient of reduced hemoglobin is always larger than the absorption coefficient of oxyhemoglobin is irradiated is conceivable. Then, in accordance with the irradiation of NB2 light according to such a modification, in the first display mode, the luminance value of the NR1 image multiplied by the coefficient C1 or the luminance value of the NR2 image multiplied by the coefficient C1 is used as the R channel. Assigning a luminance value obtained by assigning the NB1 image and the NB2 image to the G channel and assigning a luminance value obtained by adding the NB1 image and the NB2 image to the B channel 4 may be performed.

  Here, the value of the coefficient C1 calculated in the processing in the first display mode of the present modification increases or decreases with the same tendency as the coefficient C2.

  Therefore, according to the process in the first display mode of the present modification, an observation image in which the red luminance value varies according to the level of oxygen saturation in the blood is generated.

  As a result, in the first display mode of the present modification, for example, the red intensity of the pixels belonging to the region where a lesion site such as a venule or cancer is present is relatively lowered, and an arteriole is present. An observation image in which the red intensity of the pixels belonging to the region is relatively increased is displayed on the display device 4.

(Second embodiment)
10 to 15 relate to a second embodiment of the present invention.

  In the present embodiment, detailed description of portions having the same configuration as the first embodiment is omitted, and portions having different configurations from the first embodiment are mainly described. FIG. 10 is a diagram illustrating a configuration of a main part of the living body observation system according to the second embodiment.

  As shown in FIG. 10, the living body observation system 101 </ b> A is a light source device 2 </ b> A that supplies light used for observing the subject via an endoscope 1 and a light guide 6 inserted and disposed inside the endoscope 1. A processor 3, a display device 4, and an input device 5.

  The light source device 2A includes an illumination control unit 21, and a light emitting unit 22A including a white light generation unit 22a and a special light generation unit 22c.

  For example, when the illumination control unit 21 detects that the observation mode of the living body observation system 101 is set to the special light observation mode based on the system control signal output from the processor 3, the illumination control unit 21 sets the white light generation unit 22a. In addition to extinction, the special light generator 22c generates an illumination control signal for generating NB1 light, NB2 light, NR1 light, NR2 light, and NG light (described later) in a predetermined order, and generates the generated illumination control signal. It is configured to output to the light emitting unit 22.

  The special light generation unit 22c includes, for example, a plurality of LEDs, and individually or NB1 light, NB2 light, NR1 light, NR2 light, and NG light based on the illumination control signal output from the illumination control unit 21. It is comprised so that it can generate | occur | produce simultaneously. FIG. 11 is a diagram for explaining an example of the wavelength of light emitted from the light source device in the special light observation mode in the second embodiment.

  For example, as shown in FIG. 11, the NG light has a wavelength in the green region as a peak wavelength λP5 and a wavelength band that does not overlap with the NB2 light and the NR1 light (in the green region). In the present embodiment, the peak wavelength λP5 is preferably set to either 540 nm or a predetermined wavelength near 540 nm.

  That is, the imaging unit 12 according to the present exemplary embodiment captures the subject illuminated with the NR1 light and the subject illuminated with the NR2 light with a pixel group having sensitivity in the red region, and the subject illuminated with the NG light in the green region. An image is picked up by a pixel group having sensitivity, and a subject illuminated by NB1 light and a subject illuminated by NB2 light are picked up by a pixel group having sensitivity in a blue region.

  For example, when the image signal processing unit 32 detects that the observation mode of the living body observation system 101 is set to the special light observation mode based on the system control signal output from the control unit 34, the preprocessing unit 31. The processing for separating the image signal output from the NB1 component, the NB2 component, the NR1 component, the NR2 component, and the color component of the NG component obtained by imaging the reflected light (return light) of the NG light Configured to do.

  When the image signal processing unit 32 detects that the setting for displaying the observation image in the first display mode has been made based on the system control signal output from the control unit 34, for example, A coefficient C3 is calculated by performing an inter-image calculation using the NB1 component and the NB2 component among the color components separated in this way, and the calculated coefficient C3 is multiplied by the NG component and output to the observation image generation unit 33. It is configured as follows.

  Further, when the image signal processing unit 32 detects that the setting for displaying the observation image in the second display mode has been made based on the system control signal output from the control unit 34, for example, The coefficient C4 is calculated by performing the inter-image calculation using the NR1 component and the NR2 component among the color components separated in this way, and the observed coefficient generator is multiplied by the calculated coefficient C4 and the NR1 component and the NR2 component, respectively. It is comprised so that it may output to 33.

  Based on the system control signal output from the control unit 34, the observation image generation unit 33 is output from the image signal processing unit 32, for example, when the observation mode of the living body observation system 101 is set to the special light observation mode. The luminance value obtained by adding the NR1 component and the NR2 component is assigned to the R channel, the luminance value of the NG component output from the image signal processing unit 32 is assigned to the G channel, and is output from the image signal processing unit 32. An observation image is generated by assigning a luminance value obtained by adding the NB1 component and the NB2 component to the B channel, and the generated observation image is output to the display device 4.

  Next, the operation of the living body observation system 101A according to the present embodiment will be described. Hereinafter, for the sake of simplicity, description of specific operations when the observation mode of the living body observation system 101A is set to the white light observation mode is omitted. In the following, for the sake of simplicity, processing based on the NB1 image, NB2 image, NR1 image, NR2 image, and NG image corresponding to each color component obtained by separating the image signal from the preprocessing unit 31 is performed on the image signal. A description will be given assuming that the processing is performed in the processing unit 32.

  The user turns on the power of each part of the living body observation system 101, sets the observation mode of the living body observation system 101 to the white light observation mode, and then confirms the observation image (white light image) displayed on the display device 4. Then, the insertion portion of the endoscope 1 is inserted into the subject.

  Then, the user, for example, makes the distance between the distal end surface of the distal end portion of the insertion portion of the endoscope 1 and the surface of the biological tissue that is the subject be an observation distance L1 corresponding to mid-range to far-field observation. In the state where the tip portion is arranged at a proper position, the observation mode of the living body observation system 101 is switched to the special light observation mode by operating the observation mode switch 13a and the display mode switch 13b, and the first display mode An instruction for displaying the observed image is given.

  When the control unit 34 detects that the observation mode of the living body observation system 101A is set to the special light observation mode, for example, the timing of simultaneously generating NB1 light, NR2 light, and NG light, and NB2 light and NR1 light simultaneously. After the generation timing is set to be different from each other, a system control signal that can specify each of the set timings is generated and output to the illumination control unit 21, the image signal processing unit 32, and the observation image generation unit 33. To do. In addition, the control unit 34 generates a system control signal for performing an operation corresponding to the first display mode, and outputs the system control signal to the image signal processing unit 32. According to such control of the control unit 34, when the primary color filter 121 is provided in the imaging device 12b, the frame rate of the observation image displayed on the display device 4 in the special light observation mode is optimized. can do. In addition, by performing control for simultaneously generating NB1 light, NR2 light, and NG light, it is possible to reduce color mixing in the same pixel.

  Note that, according to the present embodiment, in the special light observation mode, as long as it is the timing at which the imaging signals corresponding to the NB1 light, the NB2 light, the NR1 light, the NR2 light, and the NG light can be obtained individually, The NB1 light, the NB2 light, the NR1 light, the NR2 light, and the NG light may be generated at different timings.

  Based on the system control signal output from the control unit 34, the illumination control unit 21 performs control for simultaneously generating NB1 light, NR2 light, and NG light, and control for simultaneously generating NB2 light and NR1 light, Are sequentially repeated for the special light generator 22c. Then, in accordance with such control of the illumination control unit 21, NB1 light, NR2 light and NG light, NB2 light and NR1 light are sequentially irradiated through the illumination optical system 11, and reflected light from the subject (return) An imaging signal obtained by imaging (light) is output from the imaging element 12b, and an image signal generated based on the imaging signal from the imaging element 12b is output from the preprocessing unit 31.

  The image signal processing unit 32 separates the image signal output from the preprocessing unit 31 into an NB1 image, an NB2 image, an NR1 image, an NR2 image, and an NG image, and uses the luminance values of the separated NB1 image and NB2 image. Thus, the coefficient C3 corresponding to each pixel position of the NB1 image and the NB2 image is calculated by performing the inter-image calculation.

  Specifically, the image signal processing unit 32 performs a coefficient process corresponding to each pixel position of the NB1 image and the NB2 image, for example, by performing a calculation process that removes the luminance value of the NB1 image from the luminance value of the NB2 image. C3 is calculated.

  Alternatively, the image signal processing unit 32 performs, for example, arithmetic processing such as subtracting 1 from the value obtained by dividing the luminance value of the NB2 image from the luminance value of the NB2 image, thereby obtaining each pixel of the NB1 image and the NB2 image. A coefficient C3 corresponding to the position is calculated.

  The image signal processing unit 32 outputs the NB1 image, the NB2 image, the NR1 image, and the NR2 image obtained by separating the image signal output from the preprocessing unit 31 to the observation image generation unit 33. In addition, the image signal processing unit 32 multiplies the luminance value of the corresponding pixel position in the NG image by the coefficient C3 calculated for each pixel position by the above-described inter-image calculation, and outputs the result to the observation image generation unit 33.

  The observation image generation unit 33 assigns the luminance value obtained by adding the NR1 image and the NR2 image output from the image signal processing unit 32 to the R channel, and the luminance value of the NG image output from the image signal processing unit 32 Is assigned to the G channel, the luminance value obtained by adding the NB1 image and the NB2 image output from the image signal processing unit 32 is assigned to the B channel, an observation image is generated, and the generated observation image is displayed on the display device. Output to 4.

  Here, the value of the coefficient C3 calculated by the above-described calculation between images increases or decreases in the same tendency as the coefficient C1 described in the first embodiment.

  Therefore, according to the processing in the first display mode in the present embodiment, an observation image in which the green luminance value varies according to the magnitude of oxygen saturation in the blood is generated. Specifically, according to the processing in the first display mode in the present embodiment, for example, the green luminance value in a pixel having a low oxygen saturation level in blood is relatively large (see FIG. 12). ) And an observation image in which the green luminance value at a pixel having a high oxygen saturation level in the blood is relatively small (see FIG. 13) is generated. FIG. 12 is a diagram for explaining an example of the luminance value of the pixel included in the observation image generated in the first display mode in the second embodiment. FIG. 13 is a diagram for explaining an example of luminance values of pixels different from those in FIG. 12 included in the observation image generated in the first display mode in the second embodiment.

  As a result, in the first display mode of this embodiment, for example, an observation image in which the red intensity of the pixels belonging to the region where the arteriole is present is increased is displayed on the display device 4. In other words, in the first display mode of the present embodiment, an observation image having a color tone that can distinguish the capillaries and lesion sites on the mucosal surface layer with the intensity of red is displayed on the display device 4.

  According to the present embodiment, for example, the coefficient C3 is not limited to being directly multiplied by the NG image. For example, the coefficient C3 is selected from the look-up table configured so that the output value decreases as the oxygen saturation increases. May be extracted and the NG image may be multiplied by the extracted output value.

  On the other hand, the user, for example, a position where the distance between the distal end surface of the distal end portion of the insertion portion of the endoscope 1 and the surface of the biological tissue that is the subject is an observation distance L2 corresponding to the close-up magnification observation. In the state where the distal end portion is arranged, an instruction for displaying an observation image in the second display mode is performed by operating the display mode changeover switch 13b.

  The control unit 34 generates a system control signal for performing an operation corresponding to the second display mode, and outputs the system control signal to the image signal processing unit 32.

  The image signal processing unit 32 separates the image signal output from the preprocessing unit 31 into an NB1 image, an NB2 image, an NR1 image, an NR2 image, and an NG image, and uses the luminance values of the separated NR1 image and NR2 image. Thus, the coefficient C4 corresponding to each pixel position of the NR1 image and the NR2 image is calculated by performing the inter-image calculation.

  Specifically, the image signal processing unit 32 performs a coefficient process corresponding to each pixel position of the NR1 image and the NR2 image, for example, by performing a calculation process that removes the luminance value of the NR1 image from the luminance value of the NR2 image. C4 is calculated.

  Alternatively, the image signal processing unit 32 performs, for example, arithmetic processing such that 1 is subtracted from a value obtained by dividing the luminance value of the NR2 image from the luminance value of the NR2 image, whereby each pixel of the NR1 image and the NR2 image. A coefficient C4 corresponding to the position is calculated.

  The image signal processing unit 32 outputs the NB1 image, the NB2 image, and the NG image obtained by separating the image signal output from the preprocessing unit 31 to the observation image generation unit 33. Further, the image signal processing unit 32 multiplies the luminance value at the corresponding pixel position in the NR1 image and the NR2 image by the coefficient C4 calculated for each pixel position by the above-described inter-image calculation, and outputs the result to the observation image generation unit 33. To do.

  The observation image generation unit 33 assigns the luminance value obtained by adding the NR1 image and the NR2 image output from the image signal processing unit 32 to the R channel, and the luminance value of the NG image output from the image signal processing unit 32 Is assigned to the G channel, the luminance value obtained by adding the NB1 image and the NB2 image output from the image signal processing unit 32 is assigned to the B channel, an observation image is generated, and the generated observation image is displayed on the display device. Output to 4.

  Here, the value of the coefficient C4 calculated by the above-described inter-image calculation increases or decreases in the same tendency as the coefficient C2 described in the first embodiment.

  Therefore, according to the processing in the second display mode in the present embodiment, an observation image in which the red luminance value varies according to the level of oxygen saturation in the blood is generated. Specifically, according to the processing in the second display mode in the present embodiment, for example, the red luminance value in a pixel having a high oxygen saturation level in blood is relatively increased (see FIG. 14). ) And an observation image in which the red luminance value in the pixel having a low oxygen saturation level in the blood is relatively small (see FIG. 15) is generated. FIG. 14 is a diagram for explaining an example of luminance values of pixels included in an observation image generated in the second display mode in the second embodiment. FIG. 15 is a diagram for explaining an example of luminance values of pixels different from those in FIG. 14 included in the observation image generated in the second display mode in the second embodiment.

  As a result, in the second display mode of the present embodiment, for example, an observation image in which the blue intensity of the pixels belonging to the region where the thick vein exists is displayed on the display device 4. That is, in the second display mode of the present embodiment, an observation image having a color tone capable of visually distinguishing the large-diameter artery and the large-diameter vein in the submucosa in the red to blue color gamut is displayed. It is displayed on the device 4.

  According to the present embodiment, for example, not only the coefficient C4 is directly multiplied by the NR1 image and the NR2 image, but, for example, in a look-up table configured such that the output value increases as the oxygen saturation increases. It is also possible to extract one output value corresponding to the coefficient C4 from the NR1 image and multiply the NR1 image and the NR2 image by the extracted one output value.

  As described above, according to the present embodiment, when the first display mode is set, the color tone that can easily visually identify the boundary between the normal site and the lesion site on the mucous membrane surface layer is provided. An observation image can be displayed on the display device 4. In addition, according to the present embodiment, when the second display mode is set, an observation image having a color tone that can visually distinguish a large vein and a large artery in the submucosal layer visually is displayed. 4 can be displayed. Furthermore, according to the present embodiment, in the first display mode and the second display mode, it is possible to cause the display device 4 to display an observation image in which the color tone of the entire image is similar to the white light observation mode.

  Therefore, according to the present Example, the efficiency at the time of performing surgical treatments, such as ESD (endoscopic submucosal dissection), etc. with respect to a lesion site | part can be improved.

  In addition, according to the present Example, the process for simultaneously displaying the observation image generated in the first display mode and the observation image generated in the second display mode on the display device 4 is performed. It may be.

  Further, according to the present embodiment, in the first display mode, for example, the luminance value of the NG image is assigned to the R channel, and the NB1 image multiplied by the coefficient C3 and the NB2 image multiplied by the coefficient C3 are added. The luminance value obtained in this way may be assigned to the G channel, and the observation image generated by assigning the luminance value obtained by adding the NB1 image and the NB2 image to the B channel may be displayed on the display device 4.

  On the other hand, according to the present embodiment, instead of the NB2 light as described above, for example, the peak wavelength λP2 includes 440 nm, which is a wavelength at which the absorption coefficient of reduced hemoglobin is larger than the absorption coefficient of oxidized hemoglobin, A modification in which NB2 light having a wavelength band in which the absorption coefficient of reduced hemoglobin is always larger than the absorption coefficient of oxyhemoglobin is irradiated is conceivable. Then, in accordance with the irradiation of NB2 light according to such a modification, the luminance value of the NR1 image multiplied by the coefficient C3 and the luminance value of the NR2 image multiplied by the coefficient C3 are added in the first display mode. A display device displays an observation image generated by assigning the brightness value obtained by assigning to the R channel, assigning the brightness value of the NG image to the G channel, and assigning the brightness value obtained by adding the NB1 image and the NB2 image to the B channel 4 may be performed.

  Here, the value of the coefficient C3 calculated in the processing in the first display mode of the present modification increases or decreases with the same tendency as the coefficient C2 described in the first embodiment.

  Therefore, according to the process in the first display mode of the present modification, an observation image in which the red luminance value varies according to the level of oxygen saturation in the blood is generated.

  As a result, in the first display mode of the present modification, for example, the red intensity of the pixels belonging to the region where a lesion site such as a venule or cancer is present is relatively lowered, and an arteriole is present. An observation image in which the red intensity of the pixels belonging to the region is relatively increased is displayed on the display device 4.

  The present invention is not limited to the above-described embodiments, and various modifications and applications can be made without departing from the spirit of the invention.

DESCRIPTION OF SYMBOLS 1 Endoscope 2,2A Light source device 3 Processor 4 Display apparatus 5 Input device 6 Light guide 12 Imaging part 13 Scope switch 13a Observation mode change switch 13b Display mode change switch 21 Illumination control part 22, 22A
22a White light generation units 22b and 22c Special light generation unit 32 Image signal processing unit 33 Observation image generation unit 34 Control units 101 and 101A Living body observation system

Japanese Unexamined Patent Publication No. 2012-66065

Claims (6)

The first illumination light whose extinction coefficient changes according to the oxygen saturation of blood hemoglobin in a predetermined wavelength band, and a wavelength at which the absorption coefficient of oxyhemoglobin and the absorption coefficient of reduced hemoglobin are equal in the predetermined wavelength band Second illumination light including a certain first isosbestic point wavelength and third illumination light having one or more wavelength bands in a wavelength band longer than the predetermined wavelength band are generated. A configured lighting unit;
An imaging unit configured to image return light from a subject irradiated with illumination light emitted from the illumination unit;
In a predetermined observation state, the predetermined image is calculated by performing an inter-image calculation between the image signal of the subject when the first illumination light is irradiated and the image signal of the subject when the second illumination light is irradiated. An information acquisition unit configured to acquire information on oxygen saturation of the subject in a wavelength band;
In the predetermined observation state, when generating image information reflecting information on the oxygen saturation of the subject in the predetermined wavelength band, and observing the subject in an enlarged manner than the predetermined observation state, the first An image information generation unit configured to generate image information based on an image signal of the subject when the illumination light of 3 is irradiated;
A living body observation system comprising: The illuminating unit includes, as the third illuminating light, fourth illuminating light in a wavelength band in which an extinction coefficient changes in accordance with oxygen saturation of blood hemoglobin in the long wavelength wavelength band, and the long wavelength wavelength. Generating a fifth illumination light which is a reference light used for comparison with the fourth illumination light in a band;
Furthermore, the information acquisition unit, when magnifying and observing the subject from the predetermined observation state, the image signal of the subject and the fifth illumination light when the fourth illumination light is irradiated. To obtain information on the oxygen saturation of the subject in the wavelength band of the long wavelength by an inter-image calculation with the image signal of the subject at the time of irradiation,
The image information generation unit obtains information on the oxygen saturation of the subject in the long-wavelength wavelength band acquired by the information acquisition unit when the subject is magnified and observed than the predetermined observation state. The living body observation system according to claim 1, wherein the reflected image information is generated. In the predetermined wavelength band, the illuminating unit includes the first and the like in which the extinction coefficients of oxyhemoglobin and reduced hemoglobin are shorter than the peak wavelength of the first illuminating light in the predetermined wavelength band. Light having a wavelength including an absorption point wavelength is generated, and the fifth illumination light is a first of oxyhemoglobin and reduced hemoglobin on the shorter wavelength side than the peak wavelength of the fourth illumination light in the long wavelength band. The living body observation system according to claim 2, wherein light having a wavelength including two isosbestic point wavelengths is generated. The predetermined wavelength band is a blue wavelength band;
The long wavelength band is a red wavelength band,
The imaging unit includes a pixel group having a sensitivity peak in the blue wavelength band, and a pixel group having a sensitivity peak in the red wavelength band,
Further, the timing for simultaneously generating the first illumination light and the fourth illumination light and the timing for simultaneously generating the second illumination light and the fifth illumination light are made different from each other. The living body observation system according to claim 2, further comprising a control unit configured to control the illumination unit. The image information is image information having red, green, and blue color components input to a display device that displays an image of the subject,
The image information generation unit generates image information in which information on oxygen saturation of the subject in the predetermined wavelength band is reflected in the green color component in the predetermined observation state. The living body observation system according to 4. The image information generation unit, when observing the subject in an enlarged manner than the predetermined observation state, the oxygen saturation of the subject in the wavelength band of the long wavelength to a color component different from the green color component The living body observation system according to claim 5, wherein the image information reflecting the information on is generated.

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