JP2005342350A - Illumination optical system for endoscope - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an illumination optical system for an endoscope capable of guiding light for measurement to the distal end of an insertion part and simultaneously guiding light obtained from an object by the light to the outside of the insertion part for the measurement. <P>SOLUTION: The proximal end of a light guide 16 incorporated in a fluorescent observation endoscope 10 is branched into two. Inside a light source block 21, converging lenses and lamps are arranged respectively along the extension line of the center axes of the respective branching parts 16a and 16b of the light guide 16. A first lamp 214 emits the light for object observation and a second lamp 218 emits the light for spectrometry. Between the respective branching parts and the respective converging lenses, a half mirror 221 for partially reflecting the light from the first lamp 214 and a first total reflection mirror 222 for reflecting the reflected light to a second branching part 21b are inserted only under an observation mode, and a second total reflection mirror 220 for reflecting the light emitted from a first branching part 16a toward a spectroscope 219 is inserted only under a spectroscopic mode. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an illumination optical system for an endoscope that guides light toward a distal end of an insertion portion of the endoscope and irradiates the light toward a subject.

  Endoscopes have an insertion part that is inserted into a dark hole regardless of whether it is a rigid endoscope or a flexible endoscope, and whether it is a medical endoscope or an industrial endoscope. An objective optical system for forming an image of a subject in the hole is fitted at the distal end of the insertion portion, and an imaging device for capturing the image is incorporated in the insertion portion. Yes. Further, a light guide for guiding illumination light from the base portion of the insertion portion to the tip is led through, and the illumination light guided by the light guide and emitted from the tip is transmitted to the tip of the insertion portion. The light is irradiated toward the subject (field of view by the objective optical system) through the formed illumination window. Since a part of the reflected light of the illumination light irradiated on the subject in this way enters the objective optical system, an image of the subject is formed, and this image is transmitted to the outside of the endoscope. is there.

  In the case of a medical endoscope, excitation light having a wavelength that excites living tissue and emits fluorescence is guided by the light guide to irradiate the subject (inside the body cavity) and is generated by the excitation light. In some cases, a configuration is adopted in which an image formed by the objective optical system is picked up by the fluorescent light, and a lesion site is specified based on image data obtained thereby.

As described above, the light guide for guiding the illumination light and the excitation light is made by bundling a large number of light guide fibers (quartz fiber, glass fiber, ultraviolet transmissive glass fiber, etc.) and mutually connecting them at both ends. It has a fixed fiber bundle structure. As a special example, as shown in Patent Document 1 below, one fiber bundle is branched into two at the base end side, and one branch is connected to the illumination light source, and the other branch is connected to the excitation light source. In addition, a configuration has also been proposed in which light from both light sources is alternately introduced into the light guide and an image is captured alternately by reflected light of illumination light and an image is captured by fluorescence.
Japanese Patent Application No. 10-243915

  By the way, in a conventional endoscope, light from a subject irradiated with illumination light or excitation light through a light guide is basically detected only by an objective optical system and an image sensor. Although the spectral spectrum of such light may indicate the state of the subject (particularly in the case of fluorescence), the spectral information cannot be obtained depending on the imaging device. Therefore, an optical probe is inserted into the forceps channel passed through the insertion part of the endoscope, and the spectrum of the light incident on the tip of the optical probe is detected by a spectrometer connected to the base end of the optical probe. In some cases, a method is used.

  However, since the optical probe is useless at times other than the spectroscopic measurement, the optical probe must be inserted into and removed from the forceps channel each time spectroscopic measurement is performed. Moreover, since the light (excitation light) necessary for the spectroscopic measurement is guided through the light guide of the endoscope, the light source device connected to the light guide and the spectroscope connected to the optical probe are Must be synchronized through means. Therefore, it is impossible to instantaneously switch between spectroscopic measurement and normal observation (image capturing by reflected light of illumination light or image capturing by fluorescence).

  Therefore, the present invention can guide the observation light to the distal end of the insertion portion of the endoscope using the entire observation light, and at the same time guides the measurement light to the distal end of the insertion portion. An object of the present invention is to provide an illumination optical system for an endoscope that can guide the light obtained from the above to the outside of the insertion portion for measurement.

  The endoscope illumination optical system according to the present invention devised to solve the above problems supplies light through the inside of the elongated insertion portion and emits the light outward from the distal end of the insertion portion. An illumination optical system for an endoscope, which is used by being pulled through the insertion portion and is bundled into one at its distal end and divided into two forks at its proximal end, respectively. A fiber bundle composed of a large number of optical fibers bundled as two branch portions, a first light source that emits observation light, and the light emitted from the first light source is condensed on the base end surface of the first branch portion. A first condensing lens, a second light source that emits light for spectroscopic measurement, a second condensing lens that condenses the light emitted from the second light source on the base end surface of the second branch portion, and a first In the mode, the optical path between the first branching unit and the first light source A half mirror that partially reflects light emitted from one light source is inserted, and light reflected by the half mirror is inserted into the first branch portion in an optical path between the second branch portion and the second light source. In the second mode, light emitted from the first branch portion instead of the half mirror is inserted in the optical path between the first branch portion and the first light source in the second mode. And an optical path switching device that inserts a second reflecting mirror that reflects the light and removes the first reflecting mirror from an optical path between the second branching unit and the second light source.

  When configured in this manner, in the first mode, the optical path switching device inserts a half mirror in the optical path between the first branching unit and the first light source, and between the second branching unit and the second light source. A first reflecting mirror is inserted in the optical path between. As a result, since the light emitted from the first light source is divided and introduced into the first branching portion and the second branching portion, all the optical fibers constituting the fiber bundle can be used to transmit this light. it can. As a result, the light guiding ability (light guiding efficiency) of the fiber bundle can be maximized, and a larger amount of light can be emitted from the distal end of the endoscope insertion portion. On the other hand, in the second mode, the optical path switching device inserts the second reflecting mirror instead of the half mirror in the optical path between the first branching unit and the first light source, and the second branching unit, the second light source, The first reflecting mirror is removed from the optical path between. As a result, the light emitted from the second light source is introduced into the base end face of the second branch portion, guided by the optical fiber group that constitutes the second branch portion, and emitted from the distal end of the endoscope insertion portion. . The light generated by the subject by this light is guided by another optical fiber constituting the fiber bundle, and emitted from the base end face of the first branch portion. The light emitted from the base end face of the first branch portion in this way is reflected by the second reflecting mirror and guided to various measuring instruments.

  According to the endoscope illumination optical system configured as described above, the observation light can be guided to the distal end of the insertion portion of the endoscope using the whole, while the light for measurement is used. Can be guided to the tip of the insertion portion, and at the same time, the light obtained from the subject by this light can be guided to the outside of the insertion portion for measurement.

  Hereinafter, an embodiment for carrying out the present invention will be described with reference to the drawings.

Embodiment 1

  FIG. 1 is a schematic configuration diagram showing a configuration of an endoscope system according to the first embodiment of the present invention. As shown in FIG. 1, the endoscope system includes a fluorescence observation endoscope 10, a light source processor device 20, and a monitor 60.

  FIG. 2 is an external view of the fluorescence observation endoscope 10 used in this endoscope system. As shown in FIG. 2, this fluorescence observation endoscope 10 includes an insertion portion 11 formed in an elongated shape for insertion into a body cavity, and an operation portion provided with an angle knob 12a and various buttons 12b. 12, a cable part 13 extending from the side surface of the operation part 12, and a connector part 14 for connecting the tip of the cable part 13 to the light source processor device 20.

  The insertion portion 11 has a tubular inner skeleton structure covered with a resin-made cladding tube, and the inner skeleton structure includes a soft portion 11a occupying most of the proximal end side, and the soft portion 11a. It is divided into a curved portion 11b located on the distal end side and a distal end rigid portion 11c located on the distal end.

  The flexible part 11a is configured by a round tube formed by spirally winding a long flat metal plate, or a metal knitted tube covering the round tube. With such a configuration, the flexible portion 11a can bend flexibly in accordance with an applied external force and can have rigidity capable of maintaining a bent state to such an extent that the body cavity wall is not damaged.

  The bending portion 11b is configured by a bending tube formed into a tubular shape that can be bent by connecting a plurality of so-called node rings. Four wires are attached to the most distal node of the bending tube, and when one of the four wires is pulled to the proximal side, the bending tube is pulled. The wire is bent so that it falls down toward the side where the wire is.

  The distal end rigid portion 11c is configured by a cylindrical tube fixed coaxially with respect to the node ring on the most distal end side of the bending tube. In the cylindrical tube, as shown in FIG. 1, an objective lens 12 that forms an image of a subject that faces the tip of the insertion portion 11, and an image sensor 30 that captures an image formed by the objective lens 12, It has been incorporated. In the optical path between the objective optical system 12 and the image sensor 30, an excitation light cut filter 19 for blocking only a light beam having a specific wavelength band used as excitation light is interposed.

  The image sensor 30 is connected to the tip of the signal line 18. The signal line 18 is sequentially passed through the distal end rigid portion 11c, the bending portion 11b, and the flexible portion 11a, and further to the connector portion 14 through the operation portion 12 and the cable portion 13. , Have been taken over. The base end of the signal line 18 is connected to a large number of terminals constituting an electrical connector 14a projecting from the end surface of the connector portion 14, and when the connector portion 14 is attached to the connector receiver of the processor device. Is connected to the video signal processing unit 27 in the light source processor device 20. The video signal processing unit 27 controls the driving of the image sensor in the distal end rigid portion 11c of the insertion unit 11, performs predetermined processing on the image data output from the image sensor, and based on the processed image data. Display the subject image on the monitor.

  Further, together with the signal line 18, the above four wires are sequentially passed through the inside of the bending tube of the bending portion 11b and the inside of the round tube of the flexible portion 11a, and the base ends thereof are The angle knob 12a of the operation unit 12 is attached. When the angle knob 12a is operated, one of the wires is pulled toward the operation portion 12 and the bending portion 11b of the insertion portion 11 is bent. The bending amount of the bending portion 11b is proportional to the operation amount of the angle knob 12a.

  Similarly to the signal line and the four wires, the thin tube functioning as the air / water supply channel and the thin tube functioning as the forceps channel 10a are curved inside the cylindrical tube of the distal end rigid portion 11c and the bending portion 11b. The tube is drawn through the tube and the round tube of the soft part 11a in order. In any of the thin tubes, the opening formed in the distal end surface of the distal end rigid portion 11c and the opening formed in the operation portion 12 are penetrated. 2 shows a forceps port 12c which is an opening of the forceps channel 10a, and a hose joint 12d for connecting a hose extending from an air / water supply device (not shown) and an air / water supply channel. .

  Further, a light guide 16 is incorporated in the flexible endoscope 10. As shown in FIG. 3, the light guide 16 bundles a large number of optical fibers (quartz fiber, glass fiber, ultraviolet transmissive glass fiber) into a single optical cable in almost the entire length thereof, and at the proximal end side. It is a fiber bundle that is only split into two forks. Then, the bundled part is drawn from the distal end of the insertion portion 11 to the connector portion 14 through the insertion portion 11, the operation portion 12, and the cable portion 13. Further, the base ends of the respective branches (first branch portion 16a and second branch portion 16b) at the base end portion are inserted and fixed into a pair of metal pipes 14b and 14c provided so as to protrude from the end face of the connector 14, respectively. Has been. Specifically, a large number of optical fibers constituting the light guide 16 are bundled together at the tip and bonded to each other, and are unraveled at the rear. Then, a group of optical fibers (shaded portions in FIG. 5a) located in the central portion on the front end face are arranged in the vicinity of the base end as a first branch portion 16a around the second branch portion 16b. Separated from the optical fiber. 5c, the base ends of the optical fibers forming the first branch portion 16a are bundled and bonded together, and as shown in FIG. 5b, the base ends of the optical fibers forming the second branch portion 16b are Bundled and bonded together. The bundle of optical fibers constituting the light guide 16 is protected from external force by being covered with a bifurcated silicon tube (not shown).

  Returning to FIG. 1, the light source processor 20 selectively introduces light (white light / excitation light / special light) into the end faces of the branch parts 16 a and 16 b of the light guide 16 of the fluorescence observation endoscope 10, Received from the image sensor 30 through the light source block 21 for spectroscopic measurement of light (autofluorescence, reflected light, scattered light) emitted from the subject emitted from the first branching unit 16a and the electrical connector 14a of the fluorescence observation endoscope 10. A video signal processing unit 27 that generates a video signal by performing image processing on the video signal, a system control unit 26 that integrally controls the light source block 21 and the video signal processing unit 27, and the system control unit 26 An operation panel 23 for inputting various instructions is mainly configured.

  Sockets 20a and 20b into which the metal pipes 14b and 14c protruding from the connector 14 of the fluorescence observation endoscope 10 are respectively inserted are provided on the side surface of the casing of the light source processor device 20. Behind each of the metal pipes 14b and 14c inserted into the sockets 20a and 20b, respectively, are a moving table 210 constituting the light source block 21, first and second condenser lenses 211 and 215, a filter wheel 212 and a motor 213. A shutter 216 and an actuator 217, and first and second lamps 214 and 218 are disposed. Specifically, the moving table 210 is placed on the extension line of the central axis of the first branch part 16a in the metal pipe 14b, and the first condenser lens 211, the filter wheel 212, the (shutter 216), and the first lamp. 214 are arranged in order. On the other hand, on the extension line of the central axis of the second branch portion 16b in the metal pipe 14c, the second condenser lens 215 (shutter 216) and the second lamp 218 are arranged with the moving table 210 placed. .

  Among these, the 1st lamp | ramp 214 as a 1st light source reflects the lamp | ramp which emits white light containing the light of the specific wavelength band used as excitation light, and the white light emitted as divergent light from this lamp | ramp as parallel light. It consists of a reflector. The filter wheel 212 includes a white light transmission filter that transmits components in the entire visible band and two excitation light transmission filters that transmit only excitation light at two positions offset by the same distance from the rotation center. Is inserted into the optical path of white light emitted as parallel light from the first lamp 214 by being driven to rotate by the motor 213. Moreover, the 1st condensing lens 211 is a lens which converges the white light and excitation light which each permeate | transmitted each filter of the filter wheel 212 to the base end surface of the 1st branch part 16a, respectively.

  On the other hand, the second lamp 218 as the second light source includes a lamp that emits light of a specific wavelength (special light) used for spectroscopic measurement, and a reflector that reflects the special light emitted from the lamp as divergent light as parallel light. And is composed of. The second condenser lens 215 is a lens that converges special light emitted as parallel light from the second lamp 218 on the base end surface of the second branching portion 16b.

  A moving table 210 as an optical path switching device installed between the branch portions 16a and 16b and the two condensing lenses 211 and 215 is a surface parallel to a plane including both optical axes of the two condensing lenses 211 and 215. The spectroscope 219, the second total reflection mirror 220, the half mirror 221, and the first total reflection mirror 222 are mounted on the optical axis of both the condenser lenses 211 and 215 by the drive motor 223. It is slid in the orthogonal direction.

  On the moving table 210, the spectroscope 219, the second total reflection mirror 220, the half mirror 221, and the first total reflection mirror 222 are arranged in order along the moving direction. Specifically, when the moving table 210 is at the position shown in FIG. 3 (hereinafter referred to as “observation mode position”), the light emitted from the first condenser lens 211 and the second condenser lens 215, respectively. The half mirror 221 and the first total reflection mirror 222 are respectively disposed at a pair of locations that are inserted into the optical path and at a certain distance between them. Further, as shown in FIG. 4, the light emitted from the second condenser lens 215 passes through a gap between the half mirror 221 and the first total reflection mirror 222 (hereinafter referred to as “spectral mode position”). The half mirror 220 is disposed at a position where the moving table 210 is inserted into the optical path of the light emitted from the first condenser lens 211 when the moving table 210 is present.

  The second total reflection mirror 220, the half mirror 221, and the first total reflection mirror 222 are configured by right-angle prisms having the same shape, and one normal line of a side surface that is in contact with the vertical is parallel to the central axis of each branch portion 16a, 16b. At the same time, they are arranged on the moving table 210 in such a posture that the side surfaces are flush with each other and the side surfaces forming the inclined surfaces are parallel to each other. The slopes of the second total reflection mirror (second reflection mirror) 220 and the first total reflection mirror (first reflection mirror) 222 are provided with a reflection coating that totally reflects light at right angles inside thereof. . Further, the inclined surface of the half mirror 221 is provided with a partial reflection coating that reflects part of the incident light and transmits the remaining part. In addition, the optical path length of the light emitted from the first lamp 214 and reaching the first branching portion 16a via the first condenser lens 211 and the half mirror 221, and the first condenser lens is emitted from the first lamp 214. The optical path length of the light reaching the second branching portion 16b via the 211, the half mirror 221, and the first total reflection mirror 222 is substantially equivalent. Therefore, the light emitted from the first lamp 214 can be condensed together at the base end surfaces of the first branch portion 16a and the second branch portion 16b.

  The spectroscope 219 is a device that performs spectrum analysis on the light totally reflected by the second total reflection mirror 220 and measures the amount of light for each spectrum.

  Note that the shutter 216 is a light shielding plate having an area larger than the cross section of the light emitted from each of the lamps 214 and 218 as parallel light, and is driven by the actuator 217 so that the moving table 210 is moved as shown in FIG. When it is in the observation mode position, it is inserted into the optical path of the special light emitted from the second lamp 218. As shown in FIG. 4, when the moving table 210 is in the spectral mode position, it is inserted into the optical path of the white light emitted from the first lamp 214. Is done.

  Returning to FIG. 1, the side surface of the housing of the light source processor device 20 is further electrically connected to each terminal constituting the electrical connector 14 a in a state where the metal pipes 14 b and 14 c are inserted into the sockets 20 a and 20 b described above. Electrodes are provided. The signal cable 18 that guides the video signal from the imaging device 30 is connected to the video signal processing unit 27 by the conduction of each terminal and each electrode, and each button (switch) 12b on the operation unit 12 is connected to the system. Connected to the control unit 26. Further, each switch constituting the operation panel 23 provided on the side surface of the casing of the light source processor device 20 is connected to the system control unit 26.

  Each time a specific switch (the button 12b on the operation unit 12 or the switch on the operation panel 23) is operated, the system control unit 26 changes the operation mode between the normal observation mode (first mode) and the fluorescence observation mode ( The mode is alternately switched between the first mode) and the spectroscopic mode (second mode). The system control unit 26 causes white light and special light to be emitted from both the lamps 214 and 218 of the light source block 21 in any of the operation modes.

  Further, in the normal observation mode, the system control unit 26 drives the drive motor 223 so that the moving table 210 of the light source block 21 moves to the observation mode position, and the shutter 216 is placed in the optical path of the special light emitted by the second lamp 218. The actuator 217 is driven so that the white light is inserted, and the motor 213 is controlled so that the white light transmission filter is inserted into the optical path of the white light emitted from the first lamp 214. As a result, the special light is blocked by the shutter 216, while the white light emitted from the first lamp 214 and transmitted through the white light transmission filter on the filter wheel 212 is divided by the half mirror 221, and one of the half lights The light passes through and enters the base end face of the first branching portion 16a as it is, and the other side is reflected by the half mirror 221, and then reflected again by the first total reflection mirror 222, and the base end face of the second branching portion 16b. Is incident on. As a result, all the optical fibers constituting the light guide 16 guide the white light to the tip of the insertion portion 11, so that the light guide efficiency of the white light as a whole of the light guide 16 does not drop unnecessarily. Part of the reflected light on the surface of the subject irradiated with the white light through the light distribution lens 17 enters the objective optical system 12 to form an image of the subject on the imaging surface of the image sensor 30. The video signal output by the imaging element 30 capturing this image is input to the video signal processing unit 27 through the electrical connector 14a.

  On the other hand, in the fluorescence observation mode, the system control unit 26 drives the drive motor 223 so that the moving table 210 of the light source block 21 moves to the observation mode position, and the shutter 216 is placed in the optical path of the special light emitted by the second lamp 218. The motor 213 is controlled such that the excitation light transmission filter is inserted into the optical path of white light emitted from the first lamp 214. As a result, the special light is blocked by the shutter 216, while the excitation light that has passed through the excitation light transmission filter on the filter wheel 212 is divided by the half mirror 221, one of which passes through the half mirror 221, and remains as the first While being incident on the base end face of the branching portion 16a, the other side is reflected by the half mirror 221, then reflected again by the first total reflection mirror 222, and then enters the base end face of the second branching portion 16b. As a result, all the optical fibers constituting the light guide 16 guide the excitation light to the distal end of the insertion portion 11, so that the light guide efficiency of the entire light guide 16 does not drop unnecessarily. The biological tissue of the subject irradiated with the excitation light via the light distribution lens 17 is excited by the excitation light and emits fluorescence. A part of the fluorescence emitted in this way is incident on the objective optical system 12 and then the excitation light component is removed by the excitation light cut filter 19 so that the image of the subject on the imaging surface of the imaging element 30 due to fluorescence. Form. The video signal output by the imaging element 30 capturing this image is input to the video signal processing unit 27 through the electrical connector 14a.

  On the other hand, in the spectroscopic mode, the system control unit 26 drives the drive motor 223 so that the moving table 210 of the light source block 21 moves to the spectroscopic mode position, and the shutter 216 is placed in the optical path of white light emitted from the first lamp 214. The actuator 217 is driven so as to be inserted, and the motor 213 is controlled so that the white light transmission filter is inserted into the optical path of the white light emitted from the first lamp 214. As a result, white light is blocked by the shutter 216, while special light emitted from the second lamp 218 enters the base end surface of the second branch portion 16b and is guided by the optical fiber that constitutes the second branch portion 16b. Then, the light guide 16 is ejected from the peripheral portion on the front end surface. A part of the light (autofluorescence, reflected light, scattered light) emitted from the subject irradiated with the special light through the light distribution lens 17 based on the special light is transmitted through the light distribution lens 17 and then the light guide. It is incident on the central portion of the tip surface. Then, this light (autofluorescence, reflected light, scattered light) is guided by the optical fiber that forms the central portion (that is, the optical fiber that forms the first branch portion 16a), and exits from the base end face of the first branch portion 16a. Then, the light is reflected by the second total reflection mirror 220 and enters the spectroscope 219.

  As described above, according to the present embodiment, in the observation mode, the special light for spectroscopic measurement is transmitted to the tip of the insertion portion 11 using a part of the light guide used to guide white light or excitation light. And the light (autofluorescence, reflected light, scattered light) emitted from the subject based on the special light is guided to the spectroscope using the remaining part of the light guide. Therefore, not only is a dedicated optical probe useful only for guiding the light (autofluorescence, reflected light, scattered light), but the position of the shutter 216 and the moving table 210 is switched by only operating the switch. This makes it possible to instantaneously switch between the observation mode (normal observation mode and fluorescence observation mode) and the spectroscopic mode.

  The system control unit 26 is also connected to the video signal processing unit 27 and notifies the video signal processing unit 27 of the current operation mode. Further, the video signal processing unit 27 is connected to the spectroscope 219 of the light source block 21 described above, and the measurement result of the spectroscope 219 is input thereto. While the operation mode notified from the system control unit 26 is the normal observation mode, the video signal processing unit 27 converts the video signal input from the image sensor 30 into a video signal and outputs the video signal to the monitor 60 as it is. . On the other hand, while the operation mode notified from the system control unit 26 is the fluorescence observation mode, the video signal processing unit 27 amplifies the input video signal and compares it with a predetermined threshold value. A portion having low luminance is identified as a lesion, and a video signal indicating the identified lesion is generated and output to the monitor 60. On the other hand, while the operation mode notified from the system control unit 26 is the spectral mode, the video signal processing unit 27 converts the spectral measurement information input from the spectroscope 219 into a video signal indicated in a graph format or the like. And output to the monitor 60.

Embodiment 2

  FIG. 6 is a schematic configuration diagram showing an endoscope system according to the second embodiment of the present invention. As shown in FIG. 6, in the second embodiment, the fluorescence observation endoscope 100 is a normal fluorescence observation endoscope in which a normal light guide 160 having only a function of guiding white light is incorporated. 100, and the light source unit of the light source processor device 200 has only a function of introducing white light into the light guide of the fluorescence observation endoscope 100. That is, when the lamp 24 supplied with a drive current from the lamp power supply 25 controlled by the system control unit 26 emits white light as parallel light, the condenser lens 29 causes the white light to be emitted from the fluorescence observation endoscope 100. The light guide 160 converges and enters the base end face. The shutter 31 is inserted into the optical path of white light emitted from the lamp 24 only in the fluorescence observation mode and the spectroscopic observation mode by the motor 28 driven by the system control unit 26.

  In the second embodiment, the probe P inserted into the forceps channel 10a of the fluorescence observation endoscope 100 has the same structure as the light guide 16 of the first embodiment, and each branch portion of the probe P is used. (The first branch portion P1 corresponding to the first branch portion 16a of the light guide 16 of the first embodiment, and the second branch portion P2 corresponding to the second branch portion 16b of the light guide 16 of the first embodiment). As the auxiliary light source / spectrometer 300, an apparatus having the same structure as the light source block 21 of the first embodiment is used.

  According to the second embodiment, the excitation light for fluorescence observation is emitted from the first lamp 214 of the auxiliary light source / spectrometer 300 and is probed from the base end surfaces of both branch parts P1 and P2 via the half mirror 221. It is injected from the distal end of the insertion portion 11 through the probe P introduced into the forceps channel 10a of the fluorescence observation endoscope 100. Therefore, according to the present embodiment, the probe P functions even in a time zone other than that in the spectroscopic mode, and is not useless. Therefore, it is not necessary to insert / remove the probe P every time the mode is switched, and in the second embodiment, the position of the shutter 216 and the moving table 210 is switched only by operating the switch. Mode, fluorescence observation mode) and spectral mode are instantaneously switched.

  The other configurations in the second embodiment are exactly the same as those in the first embodiment described above, and thus the same reference numerals are assigned to the corresponding configurations and the description thereof is omitted. In addition, since other operational effects according to the second embodiment are also the same as those of the first embodiment described above, description thereof is omitted.

Schematic which shows the internal structure of the endoscope system by the 1st Embodiment of this invention. External view of fluorescence observation endoscope Optical configuration diagram showing optical configuration of light guide and light source unit in observation mode Optical configuration diagram showing optical configuration of light guide and light source unit in spectral mode Schematic showing the configuration of each end of the light guide Schematic which shows the internal structure of the endoscope system by the 2nd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Fluorescence observation endoscope 11 Light distribution lens 12 Objective optical system 16 Light guide 16a 1st branch part 16b 2nd branch part 20 Light source processor apparatus 21 Light source block 26 System control part 30 Imaging element 210 Moving table 211 1st condensing lens 214 first lamp 215 second condenser lens 216 shutter 218 second lamp 219 spectroscope 220 first total reflection mirror 221 half mirror 222 second total reflection mirror 223 drive motor

Claims (3)

An illumination optical system for an endoscope that supplies light through the inside of a long insertion portion and emits outward from the distal end of the insertion portion,
It is used by being drawn through the insertion portion and bundled into one at its distal end, and is divided into two forks at its proximal end and bundled as a first branch portion and a second branch portion, respectively. A fiber bundle of optical fibers;
A first light source that emits light for observation;
A first condensing lens that condenses the light emitted from the first light source on the base end surface of the first branch portion;
A second light source that emits light for spectroscopic measurement;
A second condensing lens that condenses the light emitted from the second light source on the base end surface of the second branch portion;
In the first mode, a half mirror that partially reflects the light emitted from the first light source is inserted into the optical path between the first branch portion and the first light source, and the second branch portion and the first light source A first reflecting mirror that reflects the light reflected by the half mirror toward the second branch portion is inserted into the optical path between the second light source and the first branch portion and the first light source in the second mode. A second reflecting mirror that reflects the light emitted from the first branch portion instead of the half mirror is inserted in the optical path between the second light source and the second light source. An endoscope illumination optical system comprising: an optical path switching device that removes the first reflecting mirror from the optical path. 2. The internal view according to claim 1, wherein the optical path switching device includes a moving table on which at least the first reflecting mirror, the half mirror, and the second reflecting mirror are placed and moved together. Mirror illumination optics. On the moving table, there is a gap between the first reflecting mirror and the half mirror, and in the second mode, the gap between the first reflecting mirror and the half mirror is The illumination optical system for an endoscope according to claim 1, wherein an optical path between the second branch portion and the second light source passes.