JPWO2017047141A1 - Endoscope apparatus and endoscope system - Google Patents

Abstract

An endoscope apparatus can perform observation using fluorescence generated in response to irradiation of excitation light to a fluorescent dye administered into a subject and reference light that is light in a wavelength band different from fluorescence. The objective optical system into which the insertion part that can be inserted into the subject, the fluorescence, the reflected light of the reference light, and the reflected light of the excitation light are incident, and the light emitted through the objective optical system are mutually connected. A spectral element that separates light into a plurality of different wavelength bands, an imaging unit that includes an imaging element for imaging fluorescence separated by the spectral element, and light that enters from the objective optical system reaches the imaging element. And a filter unit that blocks the reflected light of the excitation light and blocks the reflected light of the reference light before the light emitted through the spectroscopic element reaches the imaging device.

Description

  The present invention relates to an endoscope apparatus and an endoscope system, and more particularly to an endoscope apparatus and an endoscope system used for fluorescence observation.

  In endoscopic observation in the medical field, for example, excitation light for exciting either a fluorescent dye administered into a subject or a predetermined fluorescent substance present in a cell of the subject is applied to a desired observation site. Conventionally, fluorescence observation, which is an observation method for diagnosing whether or not a lesion site is included in the desired observation site based on the generation state of fluorescence upon irradiation, has been performed. Further, in the above-described fluorescence observation, for example, based on the reflected light of the reference light that is emitted in response to the irradiation of the reference light that is light in a wavelength band different from that of the fluorescence, the peripheral region of the fluorescence generation location is visualized. Such a method is conventionally used. For example, Japanese Patent Application Laid-Open No. 2003-79567 discloses a configuration for performing fluorescence observation using the reflected light of the reference light described above.

  Specifically, Japanese Patent Application Laid-Open No. 2003-79567 discloses fluorescence L3 emitted in response to irradiation with excitation light L2 of 410 nm and reference light that is near-infrared light having a wavelength of 750 nm to 900 nm. The structure for displaying the fluorescence diagnostic image produced | generated based on the reflected light L6 emitted according to irradiation of L5 is disclosed. Japanese Laid-Open Patent Publication No. 2003-79567 discloses a configuration in which fluorescence L3 and reflected light L6 are propagated through an image fiber, separated by a dichroic mirror, and then captured by separate image sensors. ing.

  By the way, many spectroscopic elements such as dichroic mirrors generally do not have spectroscopic accuracy capable of separating weak light such as fluorescence contained in incident light with high accuracy.

  Therefore, for example, in the above-described fluorescence observation, when incident light including fluorescence and reference light is dispersed by a spectroscopic element such as a dichroic mirror, the reference light included in the post-spectral light emitted through the spectroscopic element As a result, a part of the image is imaged at the same time as the fluorescence, resulting in a problem that the contrast at the time of rendering the generation state of the fluorescence is lowered.

  However, Japanese Patent Application Laid-Open No. 2003-79567 does not particularly mention a method that can solve the above-described problems, that is, there are still problems corresponding to the above-described problems.

  The present invention has been made in view of the above-described circumstances, and provides an endoscope apparatus and an endoscope system capable of improving the contrast when rendering the generation state of fluorescence in fluorescence observation as compared with the conventional art. The purpose is to do.

  An endoscope apparatus according to one embodiment of the present invention includes fluorescence generated in response to irradiation of excitation light with respect to a fluorescent dye administered into a subject, and reference light that is light in a wavelength band different from the fluorescence. An endoscope apparatus capable of performing the observation used, provided at an insertion portion that can be inserted into the subject, and at a distal end portion of the insertion portion, in accordance with irradiation of the fluorescence and the reference light An objective optical system configured such that the reflected light of the reference light generated in response to the reflected light of the excitation light generated in response to irradiation of the excitation light is incident as return light, and the objective optical system A spectroscopic element configured to separate and emit the return light emitted via the light into a plurality of mutually different wavelength bands, and for imaging the fluorescence separated from the return light by the spectroscopic element An imaging unit configured to include one imaging element; and The reflected light of the excitation light is blocked before the return light incident from the object optical system passes through the spectroscopic element and reaches the one image sensor, and the light emitted through the spectroscopic element is the one image sensor. And a filter unit configured to include one or more optical filters that block the reflected light of the reference light.

  An endoscope system according to an aspect of the present invention includes excitation light for exciting a fluorescent dye administered into a subject to generate fluorescence, reference light that is light in a wavelength band different from the fluorescence, A light source device capable of supplying the reference light, an insertion part that can be inserted into the subject, a distal end of the insertion part, and the reflected light of the reference light generated in response to the irradiation of the reference light And an objective optical system configured such that reflected light of the excitation light generated in response to irradiation of the excitation light is incident as return light, and the return light emitted through the objective optical system. A spectroscopic element configured to separate and emit light in a plurality of different wavelength bands; and an image sensor for imaging the fluorescence separated from the return light by the spectroscopic element. The configured imaging unit and incident from the objective optical system The reflected light blocks the reflected light of the excitation light before reaching the one image sensor through the spectroscopic element, and the reference is made until the light emitted through the spectroscopic element reaches the one image sensor. And a filter unit including at least one optical filter that blocks reflected light.

The figure which shows the structure of the principal part of the endoscope system which concerns on a 1st Example. The figure for demonstrating an example of the specific structure of the endoscope system which concerns on a 1st Example. The figure which shows an example of the optical characteristic of the excitation light cut filter provided in the endoscope apparatus which concerns on a 1st Example. The figure which shows an example of the optical characteristic of the optical filter provided in the endoscope apparatus which concerns on a 1st Example. The figure which shows an example of the wavelength range | band of the light emitted from each light source provided in the light source device which concerns on a 1st Example. The figure which shows an example of the optical characteristic of the optical filter which concerns on the modification of a 1st Example. The figure which shows the example different from FIG. 2 of the structure of the light source device which concerns on a 1st Example. The figure which shows an example of a structure of the rotation filter provided in the light source device of FIG. The figure which shows an example of the transmission characteristic of the filter for white light observation provided in the rotation filter of FIG. The figure which shows an example of the transmission characteristic of the filter for fluorescence observation provided in the rotation filter of FIG. The figure which shows the structure of the principal part of the endoscope system which concerns on a 2nd Example. The figure which shows an example of the optical characteristic of the optical filter provided in the endoscope apparatus which concerns on a 2nd Example. The figure which shows an example of the optical characteristic of the optical filter which concerns on the modification of a 2nd Example.

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

(First embodiment)
1 to 10 relate to a first embodiment and a modification of the present invention.

  As shown in FIG. 1, the endoscope system 1A is inserted into a subject and is configured to output an image obtained by imaging a subject such as a living tissue in the subject. Predetermined image processing is performed on the endoscope apparatus 2A, the light source apparatus 3 configured to supply the light emitted to the subject to the endoscope apparatus 2A, and the image output from the endoscope apparatus 2A. A video processor 4 configured to generate and output an observation image and the like, and a display device 5 configured to display the observation image output from the video processor 4 on the screen. doing. FIG. 1 is a diagram illustrating a configuration of a main part of an endoscope system according to the first embodiment.

  The endoscope apparatus 2A performs observation using fluorescence generated in response to irradiation of excitation light to a fluorescent dye administered into the subject and reference light that is light in a wavelength band different from the fluorescence. It is configured to be able to. The endoscope apparatus 2 </ b> A includes an optical viewing tube 21 having an elongated insertion portion 6, and a camera unit 22 </ b> A that can be attached to and detached from the eyepiece 7 of the optical viewing tube 21. Yes.

  The optical viewing tube 21 includes an elongated insertion portion 6 that can be inserted into a subject, a gripping portion 8 provided at the proximal end portion of the insertion portion 6, and an eyepiece portion provided at the proximal end portion of the gripping portion 8. 7.

  As shown in FIG. 2, a light guide 11 for transmitting light supplied through the cable 13 a is inserted into the insertion portion 6. FIG. 2 is a diagram for explaining an example of a specific configuration of the endoscope system according to the first embodiment.

  As shown in FIG. 2, the emission end of the light guide 11 is disposed in the vicinity of the illumination lens 15 at the distal end of the insertion portion 6. Further, the incident end portion of the light guide 11 is disposed in a light guide base 12 provided in the grip portion 8.

  As shown in FIG. 2, a light guide 13 for transmitting light supplied from the light source device 3 is inserted into the cable 13a. A connection member (not shown) that can be attached to and detached from the light guide base 12 is provided at one end of the cable 13a. A light guide connector 14 that can be attached to and detached from the light source device 3 is provided at the other end of the cable 13a.

  At the distal end of the insertion portion 6, there are an illumination lens 15 for emitting the light transmitted by the light guide 11 to the outside, and an objective lens 17 for obtaining an optical image corresponding to the light incident from the outside. Is provided. In addition, an illumination window (not shown) in which the illumination lens 15 is arranged and an objective window (not shown) in which the objective lens 17 is arranged are provided adjacent to each other on the distal end surface of the insertion portion 6. Yes.

  As shown in FIG. 2, a relay lens 18 having a plurality of lenses LE for transmitting an optical image obtained by the objective lens 17 to the eyepiece unit 7 is provided inside the insertion unit 6. That is, the relay lens 18 has a function as a transmission optical system that transmits light incident from the objective lens 17.

  As shown in FIG. 2, an eyepiece lens 19 is provided inside the eyepiece unit 7 so that the optical image transmitted by the relay lens 18 can be observed with the naked eye.

  The camera unit 22A includes an excitation light cut filter 23, a dichroic prism 24A, an optical filter 25A, imaging elements 26A, 26B, and 26C, and a signal processing circuit 27. The imaging unit of the camera unit 22A is configured to include imaging elements 26A, 26B, and 26C.

  The excitation light cut filter 23 is disposed in front of the dichroic prism 24A, and is configured as an optical filter that removes reflected light of excitation light from light emitted through the eyepiece lens 19. Specifically, for example, as shown in FIG. 3, the excitation light cut filter 23 uses a wavelength Wd that belongs to the vicinity of the boundary between the red region and the near-infrared region of the light emitted through the eyepiece lens 19. The filter is formed as an optical filter having an optical characteristic of transmitting light other than the wavelength band Be while blocking light included in the wavelength band Be corresponding to the wavelength We longer than the wavelength Wd, which belongs to the infrared region. FIG. 3 is a diagram illustrating an example of optical characteristics of the excitation light cut filter provided in the endoscope apparatus according to the first embodiment.

  The dichroic prism 24A separates the light emitted through the excitation light cut filter 23 into light in three wavelength bands, that is, light in the red region to near infrared region, light in the green region, and light in the blue region. It is comprised as a spectroscopic element which radiate | emits.

  The optical filter 25A is disposed between the dichroic prism 24A and the image sensor 26A, and transmits light in a predetermined wavelength band belonging to the red region to the near infrared region among the light emitted through the dichroic prism 24A. On the other hand, it is formed with an optical characteristic that blocks light outside the predetermined wavelength band. Specifically, for example, as shown in FIG. 4, the optical filter 25A has a wavelength belonging to the vicinity of the boundary between the green region and the red region and shorter than the wavelength Wd to a wavelength belonging to the near infrared region and longer than the wavelength We. It is formed with optical characteristics that transmit light included in the wavelength band Bp corresponding to Wf while blocking light other than the wavelength band Bp. FIG. 4 is a diagram illustrating an example of optical characteristics of an optical filter provided in the endoscope apparatus according to the first embodiment.

  The image sensor 26A is configured by an image sensor such as a monochrome CCD, for example. Further, the image sensor 26 </ b> A is configured to perform an imaging operation according to an image sensor drive signal output from the video processor 4. The image sensor 26A captures red light to near-infrared light emitted via the dichroic prism 24A and the optical filter 25A, and generates an image corresponding to the captured red light to near-infrared light. It is configured to output.

  The image sensor 26B is configured by an image sensor such as a monochrome CCD, for example. In addition, the image sensor 26B is configured to perform an imaging operation according to an image sensor drive signal output from the video processor 4. The imaging element 26B is configured to capture green light emitted through the dichroic prism 24A, and generate and output an image corresponding to the captured green light.

  The image sensor 26C is configured by an image sensor such as a monochrome CCD, for example. The image sensor 26 </ b> C is configured to perform an imaging operation according to an image sensor drive signal output from the video processor 4. The image sensor 26C is configured to image blue light emitted through the dichroic prism 24A, and generate and output an image corresponding to the captured blue light.

  The signal processing circuit 27 performs predetermined signal processing such as correlated double sampling processing, gain adjustment processing, and A / D conversion processing on each image output from the image sensors 26A, 26B, and 26C. It is configured to apply. Further, the signal processing circuit 27 is configured to output the image subjected to the predetermined signal processing described above to the video processor 4 to which the signal cable 28 is connected.

  The light source device 3 can supply excitation light for exciting the fluorescent dye administered in the subject to generate fluorescence and reference light that is light in a wavelength band different from the fluorescence. It is configured. The light source device 3 includes a light emitting unit 31, a multiplexer 32, a condenser lens 33, and a light source control unit 34.

  The light emitting unit 31 includes a red light source 31A, a green light source 31B, a blue light source 31C, and an excitation light source 31D.

  The red light source 31A includes, for example, a lamp or an LED, and is configured to emit R light (see FIG. 5) that is red light in a wavelength band Br corresponding to the wavelength Wc to the wavelength Wd. The red light source 31 </ b> A is configured to switch between a lighting state and a light-off state according to the control of the light source control unit 34. Further, the red light source 31A is configured to generate R light having an intensity or a light amount according to the control of the light source control unit 34 in the lighting state. FIG. 5 is a diagram illustrating an example of a wavelength band of light emitted from each light source provided in the light source device according to the first embodiment.

  The green light source 31B includes, for example, a lamp or an LED, and G light that is green light in a wavelength band Bg corresponding to the wavelength Wb to the wavelength Wc belonging to the vicinity of the boundary between the blue color region and the green color region (see FIG. 5). Is configured to emit. Further, the green light source 31B is configured to be switched between a lighting state and a light-off state according to the control of the light source control unit 34. Further, the green light source 31B is configured to generate G light having an intensity or a light amount according to the control of the light source control unit 34 in the lighting state.

  The blue light source 31C includes, for example, a lamp or an LED, and is configured to emit B light (see FIG. 5) that is blue light in a wavelength band Bb corresponding to the wavelength Wa to the wavelength Wb belonging to the blue region. Yes. The blue light source 31 </ b> C is configured to switch between a lighting state and a light-off state according to the control of the light source control unit 34. Further, the blue light source 31 </ b> C is configured to generate B light having an intensity or a light amount according to the control of the light source control unit 34 in the lighting state.

  The excitation light source 31D includes, for example, a lamp or an LED, and is configured to emit EX light (see FIG. 5) that is excitation light in a wavelength band Be corresponding to the wavelength Wd to the wavelength We. Further, the excitation light source 31D is configured to be switched between a lighting state and a light-off state according to the control of the light source control unit 34. In addition, the excitation light source 31D is configured to generate EX light having an intensity or a light amount according to the control of the light source control unit 34 in the lighting state.

  The multiplexer 32 is configured to be able to multiplex each light emitted from the light emitting unit 31 and to enter the condenser lens 33.

  The condenser lens 33 is configured to collect the light incident through the multiplexer 32 and output it to the light guide 13.

  The light source control unit 34 is configured to control each light source of the light emitting unit 31 based on an illumination control signal output from the video processor 4.

  The video processor 4 includes an image sensor driving unit 41, an image processing unit 42, an input I / F (interface) 43, and a control unit 44.

  The image sensor driving unit 41 includes, for example, a driver circuit. The image sensor driving unit 41 is configured to generate and output an image sensor driving signal for driving the image sensors 26A, 26B, and 26C, respectively.

  The image processing unit 42 includes, for example, an image processing circuit. The image processing unit 42 performs white light observation by performing predetermined image processing on the image output from the endoscope apparatus 2A when the white light observation mode is set in accordance with the control of the control unit 44. An image is generated, and the generated white light observation image is output to the display device 5. Further, the image processing unit 42 performs a predetermined image processing on the image output from the endoscope apparatus 2A when the fluorescence observation mode is set in accordance with the control of the control unit 44, thereby obtaining the fluorescence observation image. The generated fluorescence observation image is output to the display device 5.

  The input I / F 43 includes one or more switches and / or buttons that can give instructions according to user operations. Specifically, the input I / F 43 gives an instruction to set (switch) the observation mode of the endoscope system 1A to either the white light observation mode or the fluorescence observation mode, for example, in accordance with a user operation. And an observation mode changeover switch (not shown) that can be used.

  The control unit 44 includes, for example, a control circuit such as a CPU or an FPGA (Field Programmable Gate Array). In addition, the control unit 44 generates an illumination control signal for emitting light according to the observation mode of the endoscope system 1A based on an instruction given in the observation mode changeover switch of the input I / F 43, and the light source control unit It is configured to output to 34. Also, the control unit 44 performs control for causing the image processing unit 42 to perform an operation according to the observation mode of the endoscope system 1A based on an instruction given by the observation mode changeover switch of the input I / F 43. It is configured as follows.

  The display device 5 includes, for example, an LCD (liquid crystal display) and the like, and is configured to display an observation image output from the video processor 4.

  Next, operations and the like of the endoscope system 1A according to the present embodiment will be described. In the present embodiment, a fluorescent dye FLP having a fluorescence characteristic that emits FL light that is fluorescence (in the near-infrared region) in the wavelength band Bf corresponding to the wavelength We to the wavelength Wf in response to the irradiation with EX light. A case where is administered into a subject will be described as an example.

  First, a user such as an operator connects each part of the endoscope system 1A and turns on the power, and then operates the input I / F 43 to change the observation mode of the endoscope system 1A to the white light observation mode. Give instructions for setting.

  When detecting that the white light observation mode is set, the control unit 44 generates an illumination control signal for emitting white light from the light source device 3 and outputs the illumination control signal to the light source control unit 34.

  The light source control unit 34 performs control for turning on the red light source 31A, the green light source 31B, and the blue light source 31C when the white light observation mode is set according to the illumination control signal output from the control unit 44. At the same time, control is performed to turn off the excitation light source 31D.

  Then, by performing the operation as described above in the light source control unit 34, the subject is irradiated with WL light that is white light including R light, G light, and B light, and according to the irradiation of the WL light. WLR light, which is reflected light emitted from the subject, enters from the objective lens 17 as return light. The WLR light incident from the objective lens 17 is emitted to the camera unit 22A through the relay lens 18 and the eyepiece lens 19.

  Here, according to the configuration of the camera unit 22A described above, the excitation light cut filter 23 has the optical characteristics as illustrated in FIG. 3, so that the WLR light emitted through the eyepiece lens 19 is excited. And enters the dichroic prism 24A. Then, the dichroic prism 24A separates the WLR light that is incident light into R light, G light, and B light, and emits them.

  Further, according to the configuration of the camera unit 22A described above, since the optical filter 25A has the optical characteristics illustrated in FIG. 4, the R light separated by the dichroic prism 24A passes through the optical filter 25A and is imaged. On the other hand, the G light and B light separated by the dichroic prism 24A can be blocked by the optical filter 25A so as not to be incident on the image sensor 26A.

  Therefore, when the observation mode of the endoscope system 1A is set to the white light observation mode, the R light included in the WLR light is imaged by the image sensor 26A, and the G light included in the WLR light is captured by the image sensor 26B. The B light included in the WLR light is imaged by the image sensor 26C. In addition, when the observation mode of the endoscope system 1A is set to the white light observation mode, the image RI that is an image obtained by imaging the R light included in the WLR light and the WLR light are included. An image GI that is an image obtained by imaging the G light and an image BI that is an image obtained by imaging the B light included in the WLR light are passed through the signal processing circuit 27 to the image processing unit 42. Is output.

  Under the control of the control unit 44, the image processing unit 42 performs, for example, image processing such as processing for superimposing the images RI, GI, and BI output from the signal processing circuit 27 one field at a time, and the white light observation image And the generated white light observation image is output to the display device 5. According to such an operation of the image processing unit 42, for example, a white light observation image having substantially the same color tone as that when a subject such as a living tissue is viewed with the naked eye is displayed on the display device 5.

  On the other hand, for example, the user administers the fluorescent dye FLP into the subject at a desired timing before setting the observation mode of the endoscope system 1A to the fluorescence observation mode.

  The user confirms the white light observation image displayed on the display device 5 and inserts the insertion portion 6 into the subject, and places the distal end portion of the insertion portion 6 in the vicinity of the desired observation site in the subject. In this state, by operating the input I / F 43, an instruction for setting the observation mode of the endoscope system 1A to the fluorescence observation mode is issued.

  When detecting that the fluorescence observation mode is set, the control unit 44 generates an illumination control signal for emitting excitation light and reference light from the light source device 3 and outputs the illumination control signal to the light source control unit 34.

  The light source control unit 34 performs control for turning on the green light source 31B, the blue light source 31C, and the excitation light source 31D when the fluorescent observation mode is set according to the illumination control signal output from the control unit 44. At the same time, control is performed to turn off the red light source 31A.

  Then, by performing the operation as described above in the light source control unit 34, the subject is irradiated with the EX light that is excitation light and the RFA light that is reference light including G light and B light. FL light emitted from the fluorescent dye FLP in response to irradiation with EX light, RLA light that is reflected light from the subject in response to irradiation with the RFA light, and the subject in response to irradiation with the EX light EXR light, which is reflected light emitted from, enters from the objective lens 17 as return light. Each light included in the return light incident from the objective lens 17 is emitted to the camera unit 22A via the relay lens 18 and the eyepiece lens 19.

  Here, according to the configuration of the camera unit 22A described above, the excitation light cut filter 23 has the optical characteristics illustrated in FIG. 3, and therefore, the EXR light emitted through the eyepiece 19 is converted into the excitation light cut filter 23. And the FL light and RLA light emitted through the eyepiece lens 19 pass through the excitation light cut filter 23 and enter the dichroic prism 24A. The dichroic prism 24A separates the FL light and RLA light included in the incident light, and further separates the RLA light into G light and B light and emits them.

  Further, according to the configuration of the camera unit 22A described above, since the optical filter 25A has the optical characteristics illustrated in FIG. 4, the FL light separated by the dichroic prism 24A passes through the optical filter 25A and is imaged. On the other hand, the G light and B light included in the RLA light separated by the dichroic prism 24A can be blocked by the optical filter 25A so as not to be incident on the image sensor 26A.

  That is, in the camera unit 22A of the present embodiment, it is possible to block the EXR light before the return light incident from the objective lens 17 passes through the relay lens 18 and the dichroic prism 24A and reaches the image pickup device 26A. A filter unit including an excitation light cut filter 23 and an optical filter 25A capable of blocking RLA light before the light emitted through the prism 24A reaches the image sensor 26A is provided.

  Therefore, when the observation mode of the endoscope system 1A is set to the fluorescence observation mode, the FL light is imaged by the image sensor 26A, the G light included in the RLA light is imaged by the image sensor 26B, and the RLA light The B light included in the image is captured by the image sensor 26C. Further, when the observation mode of the endoscope system 1A is set to the fluorescence observation mode, the image FLI which is an image obtained by imaging the FL light and the G light included in the RLA light are obtained. The image RGI that is the obtained image and the image RBI that is the image obtained by imaging the B light included in the RLA light are output to the image processing unit 42 via the signal processing circuit 27.

  Under the control of the control unit 44, for example, the image processing unit 42 performs image processing such as processing for superimposing the images FLI, RGI, and RBI output from the signal processing circuit 27 for each field, thereby generating a fluorescence observation image. The generated fluorescence observation image is output to the display device 5. According to such an operation of the image processing unit 42, for example, a fluorescence observation image capable of simultaneously confirming the generation state of the FL light and the state of the peripheral region of the generation point of the FL light is displayed. It is displayed on the device 5.

  As described above, according to the present embodiment, the return light generated in the fluorescence observation mode passes through the excitation light cut filter 23, the dichroic prism 24A, and the optical filter 25A in this order, and reaches the image sensor 26A. I have to. Therefore, according to the present embodiment, regardless of the spectral accuracy of the dichroic prism 24A, the FL light included in the return light is removed while the EXR light and the RLA light included in the return light generated in the fluorescence observation mode are removed. An image can be taken. Therefore, according to the present embodiment, it is possible to improve the contrast when rendering the generation state of fluorescence in fluorescence observation as compared with the conventional case.

  Note that the camera unit 22A of the present embodiment is not limited to the configuration in which the two filters, the excitation light cut filter 23 and the optical filter 25A, are arranged at the above-described positions to configure the filter unit. One integrated filter may be arranged between the dichroic prism 24A and the image sensor 26A to form a filter unit. Further, in such a configuration of the filter unit, for example, the one filter described above transmits light included in either the wavelength band Br or Bf as illustrated in FIG. 6, while the wavelength band Br and What is necessary is just to have the optical characteristic which interrupts | blocks the light which is not contained in any of Bf. FIG. 6 is a diagram illustrating an example of optical characteristics of an optical filter according to a modification of the first embodiment.

  In addition, by appropriately modifying the configuration of the present embodiment, for example, an insertion portion formed in an elongated shape that can be inserted into the body cavity of the subject is provided, and the objective lens 17 is provided at the distal end portion of the insertion portion, The endoscope apparatus 2A may be configured by providing the excitation light cut filter 23, the dichroic prism 24A, the optical filter 25A, and the imaging elements 26A to 26C. In such a case, the endoscope apparatus 2 </ b> A can be configured without using the relay lens 18 and the eyepiece lens 19.

  On the other hand, according to the present embodiment, instead of the light source device 3, for example, the endoscope system 1A may be configured using a light source device 3A having a configuration as shown in FIG. FIG. 7 is a diagram illustrating an example of the configuration of the light source device according to the first embodiment, which is different from FIG.

  As illustrated in FIG. 7, the light source device 3 </ b> A includes a xenon lamp 71, a filter switching device 72, a condenser lens 73, and a light source control unit 74.

  The xenon lamp 71 is configured to emit, for example, BL light that is broadband light including a band from the wavelength Wa to the wavelength We. Further, the xenon lamp 71 is configured to be switched between a lighting state and a light-off state according to the control of the light source control unit 74. Further, the xenon lamp 71 is configured to generate a quantity of BL light according to the control of the light source control unit 74 in the lighting state.

  The filter switching device 72 is emitted from the xenon lamp 71 by being rotationally driven in accordance with the control of the light source control unit 74 and a rotary filter 72A provided so as to cross the optical path of the light emitted from the xenon lamp 71 vertically. A motor 72B that switches a filter interposed on the optical path of light to one of the filters of the rotary filter 72A.

  The rotary filter 72A has, for example, a disk shape. Further, for example, as shown in FIG. 8, the rotary filter 72 </ b> A is provided with a white light observation filter 721 and a fluorescence observation filter 722. FIG. 8 is a diagram illustrating an example of a configuration of a rotary filter provided in the light source device of FIG.

  For example, as shown in FIG. 9, the white light observation filter 721 transmits light included in any one of the three wavelength bands of the wavelength band Br, the wavelength band Bg, and the wavelength band Bb. The optical characteristics are such that light contained in wavelength bands other than one wavelength band is blocked. FIG. 9 is a diagram illustrating an example of the transmission characteristics of the white light observation filter provided in the rotary filter of FIG.

  For example, as shown in FIG. 10, the fluorescence observation filter 722 transmits light included in any one of the three wavelength bands of the wavelength band Bg, the wavelength band Bb, and the wavelength band Be. It is formed with an optical characteristic that blocks light contained in a wavelength band other than the wavelength band. FIG. 10 is a diagram showing an example of transmission characteristics of the fluorescence observation filter provided in the rotary filter of FIG.

  That is, the filter switching device 72 emits one of the white light observation filter 721 and the fluorescence observation filter 722 from the xenon lamp 71 by rotationally driving the motor 72B according to the control of the light source control circuit 74. The other filter different from the one filter can be retracted from the optical path while being inserted on the optical path of the light to be transmitted.

  The condensing lens 73 is configured to condense the light incident through the filter switching device 72 and emit it to the light guide 13.

  The light source controller 74 is configured to control the xenon lamp 71 and the filter switching device 72 based on the illumination control signal output from the controller 44 of the video processor 4.

  Specifically, when the light source control unit 74 detects that the observation mode of the endoscope system 1A is set to the white light observation mode based on the illumination control signal output from the control unit 44, for example, Control for generating a predetermined amount of BL light is performed on the xenon lamp 71, and control for inserting the white light observation filter 721 on the optical path of the light emitted from the xenon lamp 71 is a filter switching device. 72 motors 72B. Further, based on the illumination control signal output from the control unit 44, for example, the light source control unit 74 detects a predetermined amount of light when detecting that the observation mode of the endoscope system 1A is set to the fluorescence observation mode. Control for generating BL light is performed on the xenon lamp 71, and control for inserting the fluorescence observation filter 722 on the optical path of the light emitted from the xenon lamp 71 is performed on the motor 72B of the filter switching device 72. It is comprised so that it may carry out with respect to.

  According to the present embodiment, even when the endoscope system 1A is configured by using the light source device 3A having the above-described configuration instead of the light source device 3, the same as described above. The effect of can be obtained.

(Second embodiment)
11 to 13 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.

  As shown in FIG. 11, the endoscope system 1B is inserted into a subject and is configured to output an image obtained by imaging a subject such as a living tissue in the subject. A predetermined image processing is performed on the endoscope apparatus 2B, the light source apparatus 3 configured to supply light applied to the subject to the endoscope apparatus 2B, and an image output from the endoscope apparatus 2B. It has a video processor 4 and a display device 5 that are configured to generate and output an observation image or the like. FIG. 11 is a diagram illustrating a configuration of a main part of the endoscope system according to the second embodiment.

  The endoscope apparatus 2B performs observation using fluorescence generated in response to irradiation of excitation light with respect to a fluorescent dye administered into a subject and reference light that is light in a wavelength band different from the fluorescence. It is configured to be able to. In addition, the endoscope apparatus 2 </ b> B includes an optical tube 21 and a camera unit 22 </ b> B that can be attached to and detached from the eyepiece 7 of the optical tube 21.

  The camera unit 22B includes an excitation light cut filter 23, a dichroic mirror 24B, an optical filter 25B, imaging elements 26D and 26E, and a signal processing circuit 27. In addition, the imaging unit of the camera unit 22B includes imaging elements 26D and 26E.

  The dichroic mirror 24B transmits light having a wavelength longer than the wavelength Wc out of the light emitted through the excitation light cut filter 23 to the imaging element 26D side, and reflects light having a wavelength of Wc or less to the imaging element 26E side. It has a good optical characteristic. That is, the dichroic mirror 24B splits the light emitted through the excitation light cut filter 23 into light of two wavelength bands, that is, light having a wavelength shorter than the wavelength Wc and light having a wavelength longer than the wavelength Wb. It is configured as an element.

  The optical filter 25B is disposed between the dichroic mirror 24B and the image sensor 26D, and transmits light in a predetermined wavelength band belonging to the red region to the near infrared region among the light emitted through the dichroic mirror 24B. On the other hand, it is formed with an optical characteristic that blocks light outside the predetermined wavelength band. Specifically, for example, as shown in FIG. 12, the optical filter 25B transmits light included in the wavelength band Bq corresponding to the wavelength Wd to the wavelength Wf, while blocking light other than the wavelength band Bq. It is formed with optical properties. FIG. 12 is a diagram illustrating an example of the optical characteristics of the optical filter provided in the endoscope apparatus according to the second embodiment.

  The image sensor 26D is configured by, for example, a highly sensitive monochrome CCD. Further, the image pickup device 26D is configured to perform an image pickup operation in accordance with an image pickup device drive signal output from the video processor 4. The imaging element 26D is configured to capture light in the wavelength band Bq emitted through the dichroic mirror 24B and the optical filter 25B, and generate and output an image corresponding to the captured light.

  The image pickup element 26E is configured by, for example, a color CCD having a primary color or complementary color filter provided on the image pickup surface. In addition, the image sensor 26E is configured to perform an imaging operation according to an image sensor drive signal output from the video processor 4. The image sensor 26E is configured to image light having a wavelength equal to or shorter than the wavelength Wc emitted through the dichroic mirror 24B, and generate and output an image corresponding to the captured light.

  The signal processing circuit 27 of the present embodiment performs predetermined signal processing such as correlated double sampling processing, gain adjustment processing, A / D conversion processing, and the like on the images output from the image sensors 26D and 26E. It is comprised so that it may give. Further, the signal processing circuit 27 is configured to output the image subjected to the predetermined signal processing described above to the video processor 4 to which the signal cable 28 is connected.

  Next, operation | movement of the endoscope system 1B of a present Example is demonstrated. In this example, as in the first example, the case where the fluorescent dye FLP is administered to the subject will be described as an example.

  First, a user such as an operator connects each part of the endoscope system 1B and turns on the power, and then operates the input I / F 43 to change the observation mode of the endoscope system 1B to the white light observation mode. Give instructions for setting.

  When detecting that the white light observation mode is set, the control unit 44 generates an illumination control signal for emitting white light from the light source device 3 and outputs the illumination control signal to the light source control unit 34.

  The light source control unit 34 performs control for turning on the red light source 31A, the green light source 31B, and the blue light source 31C when the white light observation mode is set according to the illumination control signal output from the control unit 44. At the same time, control is performed to turn off the excitation light source 31D.

  Then, by performing the operation as described above in the light source control unit 34, the subject is irradiated with WL light that is white light including R light, G light, and B light, and according to the irradiation of the WL light. WLR light, which is reflected light emitted from the subject, enters from the objective lens 17 as return light. The WLR light incident from the objective lens 17 is emitted to the camera unit 22B through the relay lens 18 and the eyepiece lens 19.

  Here, according to the configuration of the camera unit 22B described above, the excitation light cut filter 23 has the optical characteristics illustrated in FIG. 3, so that the WLR light emitted through the eyepiece lens 19 is excited. And enters the dichroic mirror 24B. The dichroic mirror 24B reflects the WLR light, which is incident light, toward the image sensor 26E.

  Therefore, when the observation mode of the endoscope system 1B is set to the white light observation mode, the WLR light is imaged by the image sensor 26E. Further, when the observation mode of the endoscope system 1B is set to the white light observation mode, an image WRI that is an image obtained by imaging the WLR light is output to the image processing unit 42 via the signal processing circuit 27. Is done.

  The image processing unit 42 generates a white light observation image by performing predetermined image processing on the image WRI output from the signal processing circuit 27 in accordance with the control of the control unit 44, and the generated white light observation image. Is output to the display device 5. According to such an operation of the image processing unit 42, for example, a white light observation image having substantially the same color tone as that when a subject such as a living tissue is viewed with the naked eye is displayed on the display device 5.

  On the other hand, for example, the user administers the fluorescent dye FLP into the subject at a desired timing before setting the observation mode of the endoscope system 1B to the fluorescence observation mode.

  The user confirms the white light observation image displayed on the display device 5 and inserts the insertion portion 6 into the subject, and places the distal end portion of the insertion portion 6 in the vicinity of the desired observation site in the subject. In this state, by operating the input I / F 43, an instruction for setting the observation mode of the endoscope system 1B to the fluorescence observation mode is given.

  When detecting that the fluorescence observation mode is set, the control unit 44 generates an illumination control signal for emitting excitation light and reference light from the light source device 3 and outputs the illumination control signal to the light source control unit 34.

  The light source control unit 34 turns on the red light source 31A, the green light source 31B, the blue light source 31C, and the excitation light source 31D when set to the fluorescence observation mode according to the illumination control signal output from the control unit 44. Control.

  Then, by performing the operation as described above in the light source controller 34, the subject is irradiated with the EX light that is the excitation light and the RFB light that is the reference light having the same wavelength band as the WL light. The FL light emitted from the fluorescent dye FLP in response to the irradiation of the EX light, the RLB light that is the reflected light emitted from the subject in response to the irradiation of the RFB light, and the irradiation of the EX light EXR light, which is reflected light emitted from the subject, enters from the objective lens 17 as return light. Each light included in the return light incident from the objective lens 17 is emitted to the camera unit 22A via the relay lens 18 and the eyepiece lens 19.

  Here, according to the configuration of the camera unit 22B described above, since the excitation light cut filter 23 has the optical characteristics illustrated in FIG. 3, the EXR light emitted through the eyepiece lens 19 is excited by the excitation light cut filter 23. And the FL light and RLB light emitted through the eyepiece lens 19 pass through the excitation light cut filter 23 and enter the dichroic mirror 24B. The dichroic mirror 24B transmits the FL light included in the incident light to the image sensor 26D side and reflects the RLB light included in the incident light to the image sensor 26E side.

  Further, according to the configuration of the camera unit 22B described above, since the optical filter 25B has the optical characteristics illustrated in FIG. 12, the FL light separated by the dichroic mirror 24B passes through the optical filter 25B and is imaged. On the other hand, the RLB light separated by the dichroic mirror 24B can be blocked by the optical filter 25B so as not to be incident on the image sensor 26D.

  That is, in the camera unit 22B of the present embodiment, it is possible to block the EXR light before the return light incident from the objective lens 17 passes through the relay lens 18 and the dichroic mirror 24B and reaches the image pickup device 26D, and dichroic. A filter unit including an excitation light cut filter 23 and an optical filter 25B capable of blocking RLB light before the light emitted through the mirror 24B reaches the image sensor 26D is provided.

  Therefore, when the observation mode of the endoscope system 1B is set to the fluorescence observation mode, FL light is imaged by the image sensor 26D and RLB light is imaged by the image sensor 26E. In addition, when the observation mode of the endoscope system 1A is set to the fluorescence observation mode, the image FLI is an image obtained by imaging the FL light and the image obtained by imaging the RLB light. The image RLI is output to the image processing unit 42 via the signal processing circuit 27.

  Under the control of the control unit 44, the image processing unit 42 generates a fluorescence observation image by performing image processing such as processing for superimposing the images FLI and RLI output from the signal processing circuit 27 for each field. The generated fluorescence observation image is output to the display device 5. According to such an operation of the image processing unit 42, for example, a fluorescence observation image capable of simultaneously confirming the generation state of the FL light and the state of the peripheral region of the generation point of the FL light is displayed. It is displayed on the device 5.

  As described above, according to the present embodiment, the return light generated in the fluorescence observation mode passes through the excitation light cut filter 23, the dichroic mirror 24B, and the optical filter 25B in this order, and reaches the image sensor 26D. I have to. Therefore, according to the present embodiment, regardless of the spectral accuracy of the dichroic mirror 24B, the FL light included in the return light is removed while the EXR light and the RLB light included in the return light generated in the fluorescence observation mode are removed. An image can be taken. Therefore, according to the present embodiment, it is possible to improve the contrast when rendering the generation state of fluorescence in fluorescence observation as compared with the conventional case.

  Note that the camera unit 22B of the present embodiment is not limited to the configuration in which the two filters, the excitation light cut filter 23 and the optical filter 25B, are arranged at the above-described positions, and the filter unit is configured. One integrated filter may be arranged between the dichroic mirror 24B and the image sensor 26D to constitute a filter unit. In the configuration of such a filter unit, for example, the one filter described above transmits light included in the wavelength band Bf as shown in FIG. 13, while blocking light other than the wavelength band Bf. What is necessary is just to have the optical characteristic. FIG. 13 is a diagram illustrating an example of optical characteristics of an optical filter according to a modification of the second embodiment.

  In addition, by appropriately modifying the configuration of the present embodiment, for example, an insertion portion formed in an elongated shape that can be inserted into the body cavity of the subject is provided, and the objective lens 17 is provided at the distal end portion of the insertion portion, The endoscope apparatus 2B may be configured by providing the excitation light cut filter 23, the dichroic mirror 24B, the optical filter 25B, the image sensor 26D, and the image sensor 26E. In such a case, the endoscope apparatus 2B can be configured without using the relay lens 18 and the eyepiece lens 19.

  On the other hand, according to the present embodiment, for example, while transmitting light included in any one of the four wavelength bands of the wavelength band Br, the wavelength band Bg, the wavelength band Bb, and the wavelength band Be, the four wavelengths By changing the optical characteristics of the fluorescence observation filter 722 so as to block light included in a wavelength band other than the band, the light source device 3A described above in the first embodiment is used instead of the light source device 3. The endoscope system 1B can be configured. And according to the present Example, even if it is a case where endoscope system 1B is comprised using light source device 3A instead of light source device 3, the same effect as the above-mentioned thing can be acquired.

  On the other hand, according to each of the embodiments and modifications described above, for example, the optical filter for setting the light amount ratio between the light amount of the excitation light supplied to the light guide 13 and the light amount of the reference light to about 15: 1. You may provide in the inside of the light source device 3. FIG. According to such a configuration, for example, the reference light generated in response to the reference light irradiation based on the exposure time of one image sensor for imaging the fluorescence generated in response to the excitation light irradiation. Even when the exposure time of another imaging device for imaging the reflected light of the other imaging device is adjusted, the saturation of the other imaging device can be prevented as much as possible.

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

  This application is filed on the basis of the priority claim of Japanese Patent Application No. 2015-180858 filed in Japan on September 14, 2015, and the above disclosed contents include the present specification, claims, It shall be cited in the drawing.

An endoscope apparatus according to one embodiment of the present invention includes fluorescence generated in response to irradiation of excitation light with respect to a fluorescent dye administered into a subject, and reference light that is light in a wavelength band different from the fluorescence. An endoscope apparatus capable of performing the observation used, provided at an insertion portion that can be inserted into the subject, and at a distal end portion of the insertion portion, in accordance with irradiation of the fluorescence and the reference light An objective optical system configured such that the reflected light of the reference light generated in response to the reflected light of the excitation light generated in response to irradiation of the excitation light is incident as return light, and the objective optical system A spectroscopic element configured to separate and emit the return light emitted via the light into a plurality of mutually different wavelength bands, and for imaging the fluorescence separated from the return light by the spectroscopic element An imaging unit configured to include one imaging element; and A first filter for blocking the reflected light of the excitation light before the return light incident reaches the front SL one imaging element from the object optical system, the first light emitted through the filter of the one A second filter that transmits the reflected light of the excitation light and the fluorescence before reaching the imaging element and blocks at least a part of the reflected light of the reference light .

An endoscope system according to an aspect of the present invention includes excitation light for exciting a fluorescent dye administered into a subject to generate fluorescence, reference light that is light in a wavelength band different from the fluorescence, A light source device capable of supplying the reference light, an insertion part that can be inserted into the subject, a distal end of the insertion part, and the reflected light of the reference light generated in response to the irradiation of the reference light And an objective optical system configured such that reflected light of the excitation light generated in response to irradiation of the excitation light is incident as return light, and the return light emitted through the objective optical system. A spectroscopic element configured to separate and emit light in a plurality of different wavelength bands; and an image sensor for imaging the fluorescence separated from the return light by the spectroscopic element. The configured imaging unit and incident from the objective optical system A first filter whose serial return light to block the reflected light of the excitation light before reaching the front SL one imaging element, by the first light emitted through the filter reaches to the one of the imaging device A second filter that transmits the reflected light of the excitation light and the fluorescence and blocks at least a part of the reflected light of the reference light .

Claims (6)

An endoscope capable of performing observation using fluorescence generated in response to irradiation of excitation light to a fluorescent dye administered into a subject and reference light having a wavelength band different from that of the fluorescence. A device,
An insertion portion that can be inserted into the subject;
Provided at the tip of the insertion portion, the fluorescence, the reflected light of the reference light generated in response to the irradiation of the reference light, the reflected light of the excitation light generated in response to the irradiation of the excitation light, An objective optical system configured to be incident as return light;
A spectroscopic element configured to separate and emit the return light emitted through the objective optical system into light of a plurality of different wavelength bands;
An imaging unit comprising one imaging element for imaging the fluorescence separated from the return light by the spectroscopic element;
The return light incident from the objective optical system blocks the reflected light of the excitation light before passing through the spectroscopic element and reaching the one image sensor, and the light emitted through the spectroscopic element is captured by the one image sensor. A filter unit configured to include one or more optical filters that block reflected light of the reference light before reaching an element;
An endoscope apparatus characterized by comprising: The filter unit is disposed in front of the spectroscopic element, and has a first optical filter having an optical characteristic that blocks the reflected light of the excitation light while transmitting the reflected light of the fluorescence and the reference light, A second optical filter that is disposed between the spectroscopic element and the one image sensor and has an optical characteristic that blocks the reflected light of the reference light while transmitting the fluorescence. The endoscope apparatus according to claim 1. The filter unit is disposed between the spectroscopic element and the one imaging element, and has an optical characteristic such that the reflected light of the excitation light and the reflected light of the reference light are blocked while transmitting the fluorescence. The endoscope apparatus according to claim 1, wherein the endoscope apparatus includes one optical filter. The spectroscopic element is configured to separate and emit the reference light included in the return light into light of a plurality of different colors,
The internal imaging according to claim 1, wherein the imaging unit further includes a plurality of other imaging elements for imaging the light of the plurality of colors emitted through the spectroscopic element. Mirror device. The endoscope according to claim 1, wherein the imaging unit further includes another imaging element for imaging the reference light separated from the return light by the spectroscopic element. apparatus. A light source device capable of supplying excitation light for generating fluorescence by exciting a fluorescent dye administered into a subject, and reference light that is light in a wavelength band different from the fluorescence;
An insertion portion that can be inserted into the subject;
Provided at the tip of the insertion portion, the fluorescence, the reflected light of the reference light generated in response to the irradiation of the reference light, the reflected light of the excitation light generated in response to the irradiation of the excitation light, An objective optical system configured to be incident as return light;
A spectroscopic element configured to separate and emit the return light emitted through the objective optical system into light of a plurality of different wavelength bands;
An imaging unit comprising one imaging element for imaging the fluorescence separated from the return light by the spectroscopic element;
The return light incident from the objective optical system blocks the reflected light of the excitation light before passing through the spectroscopic element and reaching the one image sensor, and the light emitted through the spectroscopic element is captured by the one image sensor. A filter unit configured to include one or more optical filters that block reflected light of the reference light before reaching an element;
An endoscope system comprising:

Images