JP2012205624A - Endoscope device - Google Patents

Abstract

In an endoscope apparatus provided with an insertion portion that is inserted into a body and irradiates special light to a portion to be observed in the body, the safety of the portion to be observed with respect to the special light is ensured and the white light is irradiated. An image with sufficient brightness is also obtained for the visible image.
An oversheath that is inserted into a body and that irradiates special light to a portion to be observed in the body and that can be attached to and detached from an insertion portion 30Y that receives light emitted from the portion to be observed by the special light irradiation. 35 is provided, and a diffusion part 36 for diffusing the special light emitted from the insertion part 30Y is provided in the oversheath 35.
[Selection] Figure 5

Description

  The present invention relates to an endoscope apparatus that includes an insertion portion that is inserted into a body and that irradiates special light to an observed portion within the body by the insertion portion.

  Conventionally, endoscope systems for observing tissue in a body cavity are widely known, and a normal image is obtained by imaging a portion to be observed in a body cavity by irradiation with white light, and this normal image is displayed on a monitor screen. Electronic endoscope systems have been widely put into practical use.

  In addition, as one of such endoscope systems, for example, in order to observe blood vessels running under fat and blood flow, lymph vessels, lymph flow, bile duct running, bile flow, etc. that do not normally appear on the image, An endoscope system has been proposed in which ICG (Indocyanine Green) is previously introduced into an observation part and an ICG fluorescence image is acquired by irradiating the observation part with excitation light of near infrared light.

  Here, in the endoscope system that performs near-infrared fluorescence observation as described above, the near-infrared laser light is irradiated on the irradiation surface of the observation part in order to irradiate the near-infrared laser light over a wide range. In order to avoid concentration, usually coherent laser light is often diffused and used.

  On the other hand, for example, in Patent Document 1 and Patent Document 2, it is proposed to provide a diffusing portion for diffusing light in a distal end cover or the like that is bonded and fixed to the distal end portion of the endoscope for the purpose of expanding the irradiation range of the irradiation light. Has been.

JP 2008-237790 A JP-A-4-244130

  Here, for example, in an endoscope system that captures a fluorescent image as described above and also captures a visible image by irradiation with white light, as in Patent Document 1 and Patent Document 2, When a diffusing unit is provided at the distal end of the endoscope itself, not only the excitation light but also the white light irradiated when capturing a visible image is diffused by the diffusing unit. There are cases where the brightness of the visible image is insufficient due to a decrease in illuminance. In particular, when an endoscope system is used in surgery or the like, a visible image with sufficient brightness is required.

  In addition, when a high-power laser light source is used as the excitation light source, the provision of a diffusing portion in the endoscope itself limits the area of the diffusing portion. It is difficult to perform, and safety against irradiation with high-power laser light cannot be ensured.

  The present invention has been made in view of the above problems, and can ensure the safety of the observed portion against special light such as the excitation light described above, and is sufficient for a visible image by irradiation with white light. An object of the present invention is to provide an endoscope apparatus that can pick up an image with high brightness.

  An endoscope apparatus according to the present invention includes an insertion unit that is inserted into a body, irradiates special light to an observation part in the body, and receives light emitted from the observation part by irradiation of the special light, and an insertion part And an oversheath provided in a removable manner, the oversheath having a diffusion part for diffusing the special light emitted from the insertion part.

  In the endoscope apparatus of the present invention, a cleaning mechanism that discharges cleaning liquid or gas can be provided at the tip of the oversheath.

  Moreover, a watertight member can be provided around the diffusion portion.

  Further, the oversheath can be formed in a cylindrical shape into which the insertion portion is inserted and can be configured not to rotate in the circumferential direction of the cylindrical shape.

  Further, the diffusion portion can be provided concentrically on the distal end surface of the oversheath.

  In addition, the insertion part shall irradiate the observed part with white light emitted from a white light source, and shall receive light emitted from the observed part due to the irradiation of the white light, and an oversheath is inserted. And a white light amount control for increasing the amount of white light emitted from the white light source when the attachment detection unit detects that the oversheath is attached to the insertion portion. A portion can be provided.

  Moreover, while detecting that the oversheath is attached to the insertion part by the attachment detection part, and detecting that the oversheath is attached to the insertion part, special light is emitted from the insertion part, It is possible to provide a special light emission control unit that performs control so that special light is not emitted from the insertion portion while it is not detected that the oversheath is attached to the insertion portion.

  Further, the diffusion portion can be formed from a resin.

  In addition, a lens diffusion plate can be used as the diffusion unit.

  Further, near infrared light can be used as the special light.

  Further, the insertion portion can include a light guide member that guides both the special light and the white light.

  The insertion portion may include a special light guide member that guides special light and a white light guide member that guides white light.

  According to the endoscope apparatus of the present invention, an oversheath that is inserted into the body and is detachable from the insertion part that irradiates special light to the observed part in the body is provided, and the oversheath is provided from the insertion part. Since a diffusion unit that diffuses the emitted special light is provided, when taking an image by irradiating the special light, it is possible to increase the safety against high-output special light by attaching an oversheath. In addition, it is possible to obtain a fluorescent image in a sufficient near-infrared light irradiation range, and when a bright visible image needs to be imaged, remove the oversheath to obtain sufficient brightness. A visible image can be obtained.

  Further, as compared with the case where the diffusing portion is provided in the insertion portion itself, a diffusing portion having a large area can be used, so that high-efficiency luminance dispersion is possible, and safety against special light can be sufficiently secured.

  In addition, when providing the diffusing part in the insertion part itself, it is necessary to newly design and produce a special endoscope, but if an oversheath provided with a diffusing part as in the present invention is used, A general-purpose endoscope that is not provided with a diffusing portion, particularly a rigid endoscope, can be used.

  Further, in the endoscope apparatus of the present invention, when a cleaning mechanism for discharging cleaning liquid or gas is provided at the tip of the oversheath, even if dirt is attached to the surface of the diffusion portion, this is cleaned. be able to.

  Further, when a watertight member is provided around the diffusion portion, it is possible to prevent the diffusion effect from being reduced due to adhesion of cleaning liquid or the like to the diffusion surface of the diffusion portion.

  Further, when the oversheath is configured not to rotate with respect to the insertion portion, it is possible to prevent the position of the special light emission end of the insertion portion and the position of the diffusion portion from being displaced due to rotation. .

  Further, when the diffusing portion is provided concentrically on the distal end surface of the oversheath, even if the oversheath rotates with respect to the insertion portion, the emission end of the special light and the diffusion portion of the insertion portion Therefore, the special light can be appropriately diffused.

  In addition, when the attachment detection unit detects that the oversheath is attached to the insertion unit and detects that the oversheath is attached to the insertion unit, the amount of white light emitted from the white light source is increased. In this case, a visible image with sufficient brightness can be taken without removing the oversheath from the insertion portion.

Schematic configuration diagram of a rigid endoscope system using an embodiment of an endoscope apparatus of the present invention Schematic configuration diagram of body cavity insertion part Schematic configuration diagram of the distal end of the body cavity insertion part 4-4 'sectional view of FIG. The figure which shows the structure of the front-end | tip part of an oversheath 6 is a cross-sectional view of the oversheath shown in FIG. The figure which shows schematic structure of an imaging unit The figure which shows schematic structure of a processor and a light source device The figure which shows an example of the structure which prevented the oversheath with respect to the body cavity insertion part The figure which shows an example which provided the concentric diffusion part with respect to the oversheath The figure which shows an example of the structure which changes the light quantity of white light according to attachment or detachment of an oversheath

  Hereinafter, a rigid endoscope system using an embodiment of an endoscope apparatus of the present invention will be described in detail with reference to the drawings. The present embodiment has a feature in the configuration for irradiating special light to the observed part. First, the configuration of the entire system will be described. FIG. 1 is an external view showing a schematic configuration of a rigid endoscope system 1 of the present embodiment.

  As shown in FIG. 1, the rigid endoscope system 1 of the present embodiment includes a light source device 2 that emits near-infrared light that is normal light and excitation light, and normal light and near-infrared light emitted from the light source device 2. A visible image based on the reflected light reflected from the observed part by the normal light irradiation and a fluorescent image based on the fluorescence emitted from the observed part by the near-infrared light irradiation. Rigid endoscope imaging device 10 that performs imaging, processor 3 that performs predetermined processing on image signals representing a visible image and a fluorescent image captured by rigid endoscope imaging device 10, and outputs a control signal to light source device 2, and processor 3 A monitor 4 that displays a visible image and a fluorescent image of the observed portion based on the display control signal generated in step S1, and a physiological saline in an oversheath 35 that will be described later according to a control signal from the processor 3 And a gas supply water-supply unit 6 for supplying carbon dioxide and.

  As shown in FIG. 1, the rigid endoscope imaging apparatus 10 is an imaging unit that captures a visible image of a body cavity insertion unit 30 that is inserted into a body such as an abdominal cavity or a chest cavity, and a portion to be observed guided by the body cavity insertion unit 30. 20.

  As shown in FIG. 2, the rigid endoscope imaging apparatus 10 has a body cavity insertion unit 30 and an imaging unit 20 that are detachably connected. The body cavity insertion portion 30 includes a connection member 30a, an insertion member 30b, and a cable connection port 30c.

  The connection member 30a is provided at one end 30X of the body cavity insertion part 30 (insertion member 30b). For example, the connection member 30a is fitted into an opening 20a formed on the imaging unit 20 side, whereby the imaging unit 20 and the body cavity insertion part 30 are connected. Are detachably connected.

  The insertion member 30b is inserted into the body cavity when photographing inside the body cavity, and is formed of a hard material and has, for example, a cylindrical shape with a diameter of about 5 mm. A relay lens (to be described later) for forming an image of the observed portion is accommodated inside the insertion member 30b, and the visible image of the observed portion incident from the distal end portion 30Y passes through the relay lens. The light is emitted to the imaging unit 20 side of the one end 30X.

  A cable connection port 30c is provided on the side surface of the insertion member 30b, and the optical cable LC is mechanically connected to the cable connection port 30c. Thereby, the light source device 2 and the insertion member 30b are optically connected via the optical cable LC.

  Further, as shown in FIGS. 2 and 3, an imaging lens 30d that forms a visible image reflecting the observed portion is provided at the distal end surface of the distal end portion 30Y of the insertion member 30b. Irradiation windows 30e and 30f for irradiating normal light and near infrared light substantially symmetrically with the lens 30d interposed therebetween are provided. The irradiation windows 30e and 30f are formed by polishing the tip of a bundled optical fiber to be described later.

  FIG. 4 is a sectional view taken along line 4-4 ′ of the distal end portion 30Y of the insertion member 30b shown in FIG. As shown in FIG. 4, a relay lens 32 for guiding a visible image incident on the imaging lens 30 d to the imaging unit 20 is provided in the center of the insertion member 30 b. Two light guides LG1 and LG2 in which a large number of multi-mode optical fibers 31 are bundled are extended at substantially symmetrical positions. The light guides LG1 and LG2 are bundled so that the tip surfaces thereof form crescent-shaped irradiation windows 30e and 30f as shown in FIGS.

  As shown in FIG. 1, an oversheath 35 formed in a cylindrical shape into which the distal end portion of the insertion member 30b is fitted is provided in the vicinity of the distal end portion of the insertion member 30b. The oversheath 35 is formed from, for example, a resin.

  FIG. 5 shows the configuration of the distal end portion of the oversheath 35. As shown in FIG. 5, normal light and near-infrared light emitted from the irradiation window 30e and irradiation window 30f at the distal end of the insertion member 30b are diffused and irradiated to the observed portion at the distal end portion of the oversheath 35. A diffusion unit 36 is provided. As the diffusing unit 36, for example, a lens diffusing plate (LSD: Light shaping Diffusers), a diffusing film, a diffusing sheet, a diffusing filter, or the like can be used, and any diffusing incident light can be used. It may be a thing. However, when the oversheath 35 is made disposable, it is desirable that the oversheath 35 be made of resin. The diffusing portion 36 may be insert-formed with respect to the oversheath 35 or may be bonded with an adhesive or the like.

  Further, a cleaning nozzle 37 for injecting cleaning liquid such as physiological saline supplied from the air / water supply device 6 or gas is provided at the tip of the insertion member 30b. The opening 37a of the cleaning nozzle 37 is directed to the imaging lens 30d and the diffusing unit 36, and the cleaning liquid and the gas are emitted from the opening 37a toward the imaging lens 30d and the diffusing unit 36. . In the oversheath 35, it is assumed that a pipe for guiding the cleaning liquid or gas ejected from the air / water supply device 6 to the cleaning nozzle 37 is formed. Further, the gas is used for removing water droplets after jetting dirt or cleaning liquid, and for example, carbon dioxide gas or air can be used.

  As described above, the cleaning nozzle 37 also cleans the surface of the diffusing portion 36. Therefore, when a lens diffusing plate is used as the diffusing portion 36, for example, the diffusing surface on which the surface, relief, and hologram pattern are formed. Is placed on the inner side, that is, on the side of the irradiation windows 30e and 30f of the insertion member 30b, to suppress the adhesion of liquid to the diffusion surface and the reduction of the diffusion effect. Further, in order to prevent the liquid ejected from the cleaning nozzle 37 from entering the diffusion surface side from the outer surface of the diffusion portion 36, a watertight member 36 a is provided around the diffusion portion 36. As a material of the watertight member 36a, for example, a rubber member can be used as used in underwater glasses.

  6 is a cross-sectional view taken along line 6-6 'of the oversheath 35 and the distal end portion 30Y of the insertion member 30b shown in FIG. As shown in FIG. 6, the watertight member 36a is formed so as to slightly wrap around the diffusion portion 36 toward the diffusion surface 36b, and the watertight member 36a thus formed and the distal end surface of the insertion member 30b By adhering to each other, a sealed space can be formed between the diffusion surface 36b of the diffusion portion 36 and the irradiation windows 30e and 30f, and the liquid can be prevented from flowing around the diffusion surface 36b side of the diffusion portion 36. it can.

  FIG. 7 is a diagram illustrating a schematic configuration of the imaging unit 20. The imaging unit 20 includes a first imaging system that captures a fluorescence image of the observed part imaged by the relay lens 32 in the body cavity insertion unit 30 and generates a fluorescence image signal of the observed part, and the body cavity insertion unit 30. And a second imaging system that generates a normal image signal by capturing a visible image of the observed portion formed by the relay lens 32 therein. These imaging systems are divided into two optical axes orthogonal to each other by a dichroic prism 21 having a spectral characteristic that reflects a visible image and transmits a fluorescent image.

  The first imaging system cuts light having a wavelength equal to or less than the wavelength of the excitation light reflected by the observed portion and transmitted through the dichroic prism 21 and an excitation light cut filter 22 that transmits fluorescent wavelength region illumination light, which will be described later, and a body cavity A first imaging optical system 23 that forms a fluorescent image L4 emitted from the insertion unit 30 and transmitted through the dichroic prism 21 and the excitation light cut filter 22, and a fluorescent image L4 formed by the first imaging optical system 23 And a high-sensitivity image pickup device 24 for picking up images.

  The high-sensitivity imaging element 24 detects light in the wavelength band of the fluorescent image L4 with high sensitivity, converts it into a fluorescent image signal, and outputs it. As the high sensitivity image sensor 24, for example, a monochrome image sensor can be used.

  The second imaging system is imaged by the second imaging optical system 25 and the second imaging optical system 25 that form a visible image L3 that is emitted from the body cavity insertion unit 30 and reflected by the dichroic prism 21. An image sensor 26 that captures the visible image L3 is provided.

  The image sensor 26 detects light in the visible image wavelength band, converts it into a normal image signal, and outputs it. On the image pickup surface of the image pickup element 26, color filters of three primary colors red (R), green (G) and blue (B), or cyan (C), magenta (M) and yellow (Y) are arranged in a Bayer array or a honeycomb. It is provided in an array.

  In addition, the imaging unit 20 includes an imaging control unit 27. The imaging control unit 27 performs CDS / AGC (correlated double sampling / automatic gain control) processing and A / A processing on the fluorescence image signal output from the high-sensitivity imaging device 24 and the normal image signal output from the imaging device 26. A D-conversion process is performed and output to the processor 3 via the cable 5 (see FIG. 1).

  FIG. 8 is a diagram showing a schematic configuration of the light source device 2 and the processor 3. As shown in FIG. 8, the processor 3 includes a normal image input controller 41, a fluorescence image input controller 42, an image processing unit 43, a memory 44, a video output unit 45, an operation unit 46, a TG (timing generator) 47, and a CPU 48. ing.

  The normal image input controller 41 and the fluorescence image input controller 42 include a line buffer having a predetermined capacity, and the normal image input controller 41 receives a normal image signal for each frame output from the imaging control unit 27 of the imaging unit 20. The fluorescent image input controller 42 temporarily stores a fluorescent image signal. The normal image signal stored in the normal image input controller 41 and the fluorescent image signal stored in the fluorescent image input controller 42 are stored in the memory 44 via the bus.

  The image processing unit 43 receives the normal image signal and the fluorescence image signal for each frame read from the memory 44, performs predetermined image processing on these image signals, and outputs them to the bus.

  The video output unit 45 receives the normal image signal and the fluorescence image signal output from the image processing unit 43 via the bus, performs predetermined processing to generate a display control signal, and outputs the display control signal to the monitor 4. Output.

  The operation unit 46 receives input by the operator such as various operation instructions including air / water supply instructions and control parameters. The TG 47 outputs a drive pulse signal for driving the high-sensitivity image pickup device 24, the image pickup device 26 of the image pickup unit 20, and an LD driver 55 of the light source device 2 described later. The CPU 48 controls the entire apparatus.

  The light source device 2 includes a normal light source 50 that emits normal light L1 having a broadband wavelength of about 400 to 700 nm, a condensing lens 52 that condenses the normal light L1 emitted from the normal light source 50, and a condensing lens 52. And a dichroic mirror 53 that reflects the near-infrared light L2 and causes the ordinary light L1 and the near-infrared light L2 to enter the optical fiber splitter 59. For example, a xenon lamp is used as the normal light source 50. A diaphragm 51 is provided between the normal light source 50 and the condenser lens 52, and the amount of the diaphragm is controlled based on a control signal from an ALC (Automatic light control) 58.

  The light source device 2 includes a near-infrared LD light source 54 that emits 750 to 790 nm of near-infrared light L2 as excitation light, an LD driver 55 that drives the near-infrared LD light source 54, and a near-infrared LD light source 54. A condensing lens 56 that condenses the near-infrared light L2 emitted from the light source, and a mirror 57 that reflects the near-infrared light L2 collected by the condensing lens 56 toward the dichroic mirror 53.

  As the excitation light, a narrower wavelength than that of normal light having a broadband wavelength is used. And the wavelength of excitation light is not limited to the light of the said wavelength range, It determines suitably with the kind of fluorescent pigment | dye, or the kind of biological tissue made to autofluoresce.

  The optical fiber splitter 59 allows the normal light L1 and near-infrared light L2 incident by the dichroic mirror 53 to be incident on both the first optical cable LC1 and the second optical cable LC2 at the same time. The optical cable LC shown in FIG. 1 is a combination of the first optical cable LC1 and the second optical cable LC2 shown in FIG.

  The first optical cable LC1 is optically connected to the light guide LG1 in the insertion member 30b via the cable connection port 30c, and the second optical cable LC2 is optically connected to the light guide in the insertion member 30b via the cable connection port 30c. It is optically connected to LG2.

  Next, the operation of the rigid endoscope system of this embodiment will be described.

  First, a case will be described in which both the above-described fluorescence image of ICG by irradiation with near-infrared light and a visible image by irradiation with normal light are captured. When acquiring a fluorescence image of ICG, the above-described oversheath 35 is attached to the insertion member 30 b of the body cavity insertion portion 30. Then, the body cavity insertion portion 30 with the oversheath 35 attached is inserted into the body cavity of the subject, and the distal end of the body cavity insertion portion 30 is installed in the vicinity of the observation portion (lesioned portion).

  Then, the normal light L1 emitted from the normal light source 50 of the light source device 2 and the near infrared light L2 emitted from the near infrared LD light source 54 are connected to the first optical cable LC1 and the second optical cable LC1 connected to the light source device 2. Both lights are incident on each of the light guides LG1, LG2 guided by the optical cable LC2 and extended into the body cavity insertion portion 30.

  Then, the normal light L1 and the near-infrared light L2 guided by the light guides LG1 and LG2 in the insertion member 30b are emitted from the irradiation windows 30e and 30f provided at the distal end portion 30Y of the insertion member 30b, and are oversheathed. After being diffused by the diffusion part 36 provided at the tip of 35, the part to be observed is irradiated. Since the luminance can be dispersed by the diffusion by the diffusion unit 36, the safety against the high-power near-infrared light L2 can be ensured. Further, the irradiation range of the near-infrared light L2 can be sufficiently ensured by the diffusion by the diffusion unit 36.

  Next, a visible image based on the reflected light reflected from the observed portion by the irradiation of the normal light L1 is captured, and a fluorescent image based on the fluorescence emitted from the observed portion by the irradiation of the near infrared light L2 is captured. Is done. It should be noted that ICG is administered to the observed part in advance, and fluorescence emitted from the ICG is imaged.

  Specifically, when the visible image is captured, the visible image L3 based on the reflected light reflected from the observed portion by the irradiation of the normal light L1 enters from the distal end portion 30Y of the insertion member 30b, and the insertion member The light is guided by the relay lens 32 in 30 b and emitted toward the imaging unit 20.

  The visible image L3 incident on the imaging unit 20 is reflected by the dichroic prism 21 in a direction perpendicular to the imaging element 26, and is imaged on the imaging surface of the imaging element 26 by the second imaging optical system 25, and imaging is performed. Images are sequentially taken by the element 26 at a predetermined frame rate.

  The normal image signals sequentially output from the image sensor 26 are subjected to CDS / AGC (correlated double sampling / automatic gain control) processing and A / D conversion processing in the imaging control unit 27, and then the processor via the cable 5. 3 are sequentially output.

  The normal image signal input to the processor 3 is temporarily stored in the normal image input controller 41 and then stored in the memory 44. Then, the normal image signal for each frame read from the memory 44 is subjected to gradation correction processing and sharpness correction processing in the image processing unit 43 and then sequentially output to the video output unit 45.

  Then, the video output unit 45 performs predetermined processing on the input normal image signal to generate a display control signal, and sequentially outputs the display control signal for each frame to the monitor 4. The monitor 4 displays a normal image based on the input display control signal.

  On the other hand, when capturing a fluorescent image, a fluorescent image L4 based on the fluorescence emitted from the observed portion by irradiation with near infrared light is incident from the distal end portion 30Y of the insertion member 30b, and the lens group in the insertion member 30b. Is guided toward the image pickup unit 20.

  The fluorescent image L4 incident on the imaging unit 20 passes through the dichroic prism 21 and the excitation light cut filter 22, and is then imaged on the imaging surface of the high-sensitivity imaging element 24 by the first imaging optical system 23, and has high sensitivity. Images are taken at a predetermined frame rate by the image sensor 24.

  The fluorescent image signals sequentially output from the high-sensitivity image sensor 24 are subjected to CDS / AGC (correlated double sampling / automatic gain control) processing and A / D conversion processing in the imaging control unit 27, and then passed through the cable 5. Are sequentially output to the processor 3.

  The fluorescence image signal input to the processor 3 is temporarily stored in the fluorescence image input controller 42 and then stored in the memory 44. Then, the fluorescence image signal for each frame read from the memory 44 is subjected to predetermined image processing in the image processing unit 43 and then sequentially output to the video output unit 45.

  Then, the video output unit 45 performs a predetermined process on the input fluorescent image signal to generate a display control signal, and sequentially outputs the display control signal for each frame to the monitor 4. The monitor 4 displays a fluorescent image based on the input display control signal.

  Further, as described above, when the surface of the imaging lens 30d or the diffusing unit 36 becomes dirty while the fluorescent image and the visible image are being captured, the operator uses the operation unit 46 to supply air or water. Is entered.

  The CPU 48 of the processor 3 outputs a control signal to the air / water supply device 6 in accordance with the input air / water supply instruction, and causes air or water to be supplied. As a result, a physiological saline solution or carbon dioxide gas is discharged from the cleaning nozzle 37 of the oversheath 35 toward the imaging lens 30d and the diffusing unit 36 to perform cleaning.

  Here, as described above, the oversheath 35 is attached to the body cavity insertion unit 30, and both the normal light and the near-infrared light are transmitted through the diffusing unit 36 to irradiate the observed portion. When both of the above are imaged, as for the imaging of the fluorescence image, a sufficient irradiation range can be ensured by the diffusion effect of the near infrared light by the diffusing unit 36 as described above, and safety against the near infrared light is ensured. However, when capturing a visible image, the illuminance of normal light may be reduced and the brightness may be insufficient as an adverse effect of the diffusion function of the diffusion unit 36. In particular, when a rigid endoscope system is used in surgery or the like, a visible image with sufficient brightness is required.

  Therefore, in such a case, a visible image may be captured with the oversheath 35 removed from the body cavity insertion unit 30. The action of capturing a visible image is the same as described above.

  According to the present embodiment, the diffusing unit 36 for diffusing near-infrared light is provided in the oversheath 35. Therefore, when capturing a fluorescent image, the oversheath 35 is attached and imaged to achieve high output. In the case where it is possible to ensure safety against near-infrared light and to acquire a fluorescence image in a sufficient irradiation range of near-infrared light, and when it is necessary to capture a bright visible image, the oversheath 35 A visible image with sufficient brightness can be acquired by removing the image and removing the image.

  In the rigid endoscope system of the above-described embodiment, both normal light and near infrared light are incident on each of the two light guides LG1 and LG2 in the body cavity insertion unit 30, but the present invention is not limited thereto. For example, the configuration may be such that normal light is incident on the light guide LG1 and near-infrared light is incident on the light guide LG2. In such a configuration, it is only necessary to provide the oversheath 35 with the diffusing portion 36 corresponding to the irradiation window 30f of the light guide LG2 into which near-infrared light is incident, and irradiation with the light guide LG1 into which normal light is incident. You may make it not provide the spreading | diffusion part 36 corresponding to the window 30e. Thereby, even when the oversheath 35 is attached, a visible image with sufficient brightness can be acquired.

  In the rigid endoscope system of the above embodiment, the diffusion portion 36 is provided at a position corresponding to the irradiation window 30e and the irradiation window 30f at the tip of the insertion member 30b. When the sheath 35 is rotated, the positional relationship between the irradiation windows 30e and 30f and the diffusion portion 36 is shifted, and there is a possibility that normal light and near infrared light cannot be appropriately irradiated. .

  Therefore, a configuration may be adopted in which the oversheath 35 does not rotate with respect to the circumferential direction of the insertion member 30b. Specifically, as shown in FIG. 9, for example, a convex portion 35a is formed on the inner peripheral surface of the oversheath 35, and a groove 30g that fits the convex portion 35a is formed on the outer peripheral surface of the insertion member 30b. The oversheath 35 may be configured so that the oversheath 35 is not rotated with respect to the insertion member 30b by forming and fitting the oversheath 35. The configuration in which the oversheath 35 does not rotate is not limited to this, and other configurations may be adopted.

  Further, in the rigid endoscope system of the above embodiment, two rectangular portions are provided as the diffusing portion 36. However, the present invention is not limited to this. For example, as shown in FIG. The diffusing portion 38 may be formed concentrically around the center. By forming the concentric circles in this way, normal light and near-infrared light can be appropriately irradiated even if the oversheath 35 rotates with respect to the circumferential direction of the insertion member 30b as described above. Note that the concentric circle shape here does not necessarily have to be a complete circle shape, and includes a horseshoe shape or an elliptical shape in which a part of the circle is missing.

  Further, as described above, the oversheath 35 is attached to the body cavity insertion portion 30, and both the normal light and near infrared light are transmitted through the diffusion portion 36 to irradiate the observed portion, and both the fluorescent image and the visible image are displayed. When the image is picked up, the brightness of the visible image may be insufficient.

  Therefore, for example, as shown in FIG. 11, a mounting detection unit 39 that detects whether or not the oversheath 35 is mounted on the body cavity insertion unit 30 is provided, and the mounting detection unit 39 detects the mounting of the oversheath 35. If the oversheath 35 is not attached, the amount of normal light may be larger than when the oversheath 35 is not attached. Specifically, the CPU 48 of the processor 3 outputs a control signal to the ALC 58 of the light source device 2 according to the detection signal in the mounting detection unit 39, and the ALC 58 decreases the aperture amount of the aperture 51 to increase the amount of normal light. You may do it.

  As the attachment detection unit 39, for example, an optical sensor may be provided in the oversheath 35 or the body cavity insertion unit 30, or a piezoelectric element or the like is provided in the body cavity insertion unit 30 to electrically attach the oversheath 35. You may make it detect to.

  In the above description, the light amount of the normal light is controlled based on the detection signal in the mounting detection unit 39. However, the present invention is not limited to this, and the CPU 48 changes the LD driver 55 based on the detection signal of the mounting detection unit 39. A control signal may be output and the LD driver 55 may function as an interlock by controlling the emission of near infrared light from the near infrared LD light source 54. That is, while the attachment detection unit 39 detects the attachment of the oversheath 35, near infrared light is emitted from the near infrared LD light source 54, and the attachment detection unit 39 does not detect the attachment of the oversheath 35. May not emit near-infrared light from the near-infrared LD light source 54. In addition, as described above, instead of controlling the near-infrared light emission from the near-infrared LD light source 54, for example, a shutter or the like is provided on the optical path of the near-infrared light emitted from the near-infrared LD light source 54. The emission of near-infrared light from the body cavity insertion unit 30 may be controlled by opening and closing the shutter based on the detection signal of the mounting detection unit 39.

  In the rigid endoscope system of the above-described embodiment, two crescent-shaped light guides are provided in the body cavity insertion portion 30. However, the present invention is not limited to this, and three or more crescent-shaped light guides are provided. May be. The diffusion unit 36 may be provided for each light guide that receives near-infrared light.

  In the above embodiment, the fluorescent image is captured by the first imaging system. However, the present invention is not limited to this, and an image based on the light absorption characteristics of the observed part by irradiating special light to the observed part is captured. You may make it do.

  Moreover, although the said embodiment applies the endoscope apparatus of this invention to a rigid endoscope system, you may apply to an endoscope system which has not only this but a flexible endoscope, for example.

DESCRIPTION OF SYMBOLS 1 Rigid endoscope system 2 Light source device 3 Processor 4 Monitor 6 Air supply / water supply device 10 Rigid mirror imaging device 20 Imaging unit 30 Body cavity insertion part 30d Imaging lens 30e, 30f Irradiation window 31 Multimode optical fiber 32 Relay lens 35 Over sheath 36 Diffusion part 36a Watertight member 36b Diffusion surface 37 Cleaning nozzle 37a Opening 39 Mounting detector 50 Normal light source 54 Near-infrared LD light source

Claims (12)

An insertion part that is inserted into the body, irradiates the observation part in the body with special light, and receives light emitted from the observation part by irradiation of the special light;
An oversheath provided detachably on the insertion portion,
The endoscope apparatus, wherein the oversheath includes a diffusion portion that diffuses the special light emitted from the insertion portion.   The endoscope apparatus according to claim 1, wherein a cleaning mechanism that discharges cleaning liquid or gas is provided at a tip of the oversheath.   The endoscope apparatus according to claim 1, wherein a watertight member is provided around the diffusion portion.   2. The oversheath is formed in a cylindrical shape into which the insertion portion is inserted, and is configured not to rotate in the circumferential direction of the cylindrical shape. The endoscope apparatus according to any one of three.   The endoscope apparatus according to any one of claims 1 to 4, wherein the diffusing portion is provided concentrically on a distal end surface of the oversheath. The insertion part is for irradiating the observed part with white light emitted from a white light source, and for receiving light emitted from the observed part by irradiation of the white light,
An attachment detection unit for detecting that the oversheath is attached to the insertion unit;
A white light amount control unit configured to increase a light amount of white light emitted from the white light source when the attachment detection unit detects that the oversheath is attached to the insertion unit; The endoscope apparatus according to any one of claims 1 to 5. An attachment detection unit for detecting that the oversheath is attached to the insertion unit;
While the attachment detection unit detects that the oversheath is attached to the insertion unit, the special light is emitted from the insertion unit, and it is detected that the oversheath is attached to the insertion unit. The endoscope apparatus according to claim 1, further comprising: a special light emission control unit that performs control so that the special light is not emitted from the insertion unit while the insertion unit is not in operation.   The endoscope apparatus according to claim 1, wherein the diffusing portion is made of a resin.   The endoscope apparatus according to claim 1, wherein the diffusing unit is a lens diffusing plate.   The endoscope apparatus according to claim 1, wherein the special light is near infrared light.   The endoscope apparatus according to any one of claims 1 to 10, wherein the insertion portion includes a light guide member that guides both the special light and the white light.   The said insertion part is equipped with the light guide member for special lights which guides the said special light, and the light guide member for white lights which guides white light, The any one of Claim 1 to 10 characterized by the above-mentioned. The endoscope apparatus according to claim 1.

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