JP5790190B2 - Endoscope - Google Patents

Description

  The present invention relates to an endoscope.

  Endoscopes are widely used for diagnosis and surgery of digestive organs (see, for example, Patent Document 1 and Non-Patent Document 1). An endoscope is used for the purpose of observing an affected part by inserting it into the digestive tract of a patient. Therefore, the endoscope includes an elongated insertion portion, and a camera and illumination provided on the distal end surface of the insertion portion. The optical axis of the camera and the illumination extends in the longitudinal direction of the insertion portion, and the photographing range by the camera and the illumination range by the illumination are ahead of the distal end surface of the insertion portion. To observe the wall of an elongated lumen such as the esophagus, it is necessary to bend the distal end of the insertion part of the endoscope and point the distal end surface of the insertion part toward the affected part, which requires high operating skills and overlooks the disease. Will also increase.

  Endoscopes aimed at observing the walls of elongated lumens have been developed (see, for example, Patent Document 2 and Non-Patent Document 2). Such an endoscope is provided with a camera and illumination on the side surface of the insertion portion, and is suitable for observing elongated organs such as the esophagus and duodenum, but it is possible to secure a visual field in the insertion direction. difficult.

  A technique for making a diagnosis or observation by using a forceps channel provided in an endoscope and causing a small-diameter probe to approach an affected area has been developed (see Patent Documents 3 and 4). The techniques described in Patent Documents 3 and 4 are for observing an affected area using light of a different type from the illumination light of an endoscope. Diagnosis of an area that cannot be observed with illumination light and early detection of diseases It is an object. However, the image measured by the small-diameter probe and the image photographed by the camera in a state illuminated by the illumination light are different in appearance. Therefore, it is difficult to use the endoscope illumination and camera in combination with the small-diameter probe. In addition, since it is necessary to specify the position of the affected area to be observed with the small-diameter probe in advance using an endoscope camera, the diagnostic observation method using the small-diameter probe is performed when the endoscope camera is observed. It cannot be said that this technology is highly accurate in finding diseases that have been overlooked.

  Furthermore, as described in Patent Document 5, a technique of using auxiliary illumination through an endoscope channel has been developed. However, the illumination range by the technique described in Patent Document 5 is also limited, and it is necessary to point the camera of the endoscope toward the observation site, so that a complicated operation is required and there is a risk of overlooking the disease.

Japanese Patent No. 4610970 JP 2004-305770 A JP-A-11-56772 JP 2002-200037 A Japanese Utility Model Publication No. 58-115201

"Endoscope system", [online], FUJIFILM Holdings Corporation, [May 16, 2011 search], Internet (URL: http://fujifilm.jp/business/healthcare/endoscope/index.html) “Duodenoscope”, [online], FUJIFILM Holdings, Inc. [searched May 16, 2011], Internet (URL: http://fujifilm.jp/business/healthcare/endoscope/advancia/duodenum_scope/index .html)

  Therefore, a problem to be solved by the present invention is to enable observation of diseases / affected areas that may be overlooked by conventional endoscope illumination.

The invention according to claim 1 for solving the above-described problems includes an elongated insertion portion that can be inserted into a body cavity, an imaging portion provided at a distal end portion of the insertion portion, and a distal side from the distal end surface of the insertion portion. A first illuminating portion that irradiates light laterally and rearward in the extending direction from the distal end portion of the insertion portion, and provided at the distal end portion of the insertion portion. a second illumination section for illuminating the other party, the first illumination unit may have a shade for shielding the portion from the tip portion of the extending direction of the light irradiated to the rear of the first illumination unit, the shade Projecting radially outward from the outer peripheral surface of the first illumination part, the shade is located closer to the proximal end than the distal end part of the first illumination part and located further forward than the distal end face of the insertion part, The first illuminating portion is a tube extending in the longitudinal direction of the insertion portion inside the insertion portion. A hood attached to the distal end of the tube and projecting forward from the distal end surface of the insertion portion; and an optical fiber that is passed through the tube and the distal end portion is disposed in the hood. Transmits or diffuses and transmits the light emitted from the front end surface of the optical fiber, and the first illuminating unit transmits the optical fiber for light projecting and receiving optical fiber passed through the tube, the optical fiber for projecting light and the light receiving light an optical system provided in the tube or the hood so as to face the front end surface of the use optical fiber, an endoscope, characterized in Rukoto further having a.

According to the present invention, since the first illumination unit extends forward from the distal end surface of the insertion unit, the light emitted from the distal end of the first illumination unit reflects the wall of the body cavity and efficiently captures the imaging unit. Is received. That is, the light emitted from the front end portion of the first illuminating section is directed rearward, and the area ahead of the imaging section is brightened. Therefore, the image that is illuminated by the distal end of the first illumination unit and captured by the imaging unit is different from the image that is illuminated by the second illumination unit provided at the distal end of the insertion unit and captured by the imaging unit. It becomes. For example, in the case of illumination of the distal end portion of the first illumination portion, the shadow of the projection at the tip of the insertion portion is formed to extend from the root of the projection toward the distal end surface of the insertion portion, whereas the second illumination When illuminated by the part, the shadow of the protrusion at the tip of the insertion part is formed to extend from the base of the protrusion toward the opposite end surface of the insertion part. Therefore, it is possible to prevent oversight of the disease / affected part of the body cavity.

It is explanatory drawing which showed schematic structure of the endoscope. It is sectional drawing which showed schematic structure of the front-end | tip part of an endoscope. It is sectional drawing which showed schematic structure of the front-end | tip part of an endoscope. It is sectional drawing which showed schematic structure of the front-end | tip part of an endoscope. It is sectional drawing which showed schematic structure of the front-end | tip part of a 1st illumination part. It is sectional drawing which showed schematic structure of the front-end | tip part of a 1st illumination part. It is sectional drawing which showed schematic structure of the front-end | tip part of a 1st illumination part. It is sectional drawing which showed schematic structure of the front-end | tip part of a 1st illumination part. It is sectional drawing which showed schematic structure of the front-end | tip part of a 1st illumination part. It is sectional drawing which showed schematic structure of the front-end | tip part of a 1st illumination part.

  EMBODIMENT OF THE INVENTION Below, the form for implementing this invention is demonstrated using drawing. However, the embodiments described below are given various technically preferable limitations for carrying out the present invention, but the scope of the present invention is not limited to the following embodiments and illustrated examples.

FIG. 1 is an explanatory diagram showing a schematic configuration of the endoscope 1. FIG. 2 is a cross-sectional view showing a schematic configuration of the distal end portion of the endoscope 1.
As shown in FIG. 1, the endoscope 1 includes an operation unit 2, an insertion unit 3, a channel 4, a transmission cable 5, an imaging unit 7, a first illumination unit 20, a second illumination unit 8, and the like.

  The insertion portion 3 is formed in an elongated shape, and is inserted into the body cavity 99 as shown in FIG. The insertion portion 3 is flexible and performs a bending operation. A proximal end portion of the insertion portion 3 is connected to the operation portion 2, and the insertion portion 3 extends from the operation portion 2. By bending the insertion portion 3 with the operation portion 2, the insertion portion 3 can be bent freely.

  The transmission cable 5 extends in the axial direction of the insertion portion 3 inside the insertion portion 3 and the operation portion 2. The axial direction is the longitudinal direction of the insertion portion 3 and the direction in which the insertion portion 3 extends. The transmission cable 5 extends from the operation unit 2 and is connected to the endoscope processor.

  The imaging unit 7 is provided at the distal end 3 a of the insertion unit 3 and photographs the tip of the distal end surface 3 b of the insertion unit 3. A distal end portion of the transmission cable 5 is connected to the imaging unit 7 in the insertion unit 3, and an image captured by the imaging unit 7 is transmitted to the endoscope processor through the transmission cable 5. As shown in FIG. 2, the imaging unit 7 includes an imaging sensor (for example, a CCD image sensor or a CMOS image sensor) 7a and an objective lens 7b. The objective lens 7 b is attached to the distal end surface 3 b of the insertion portion 3 so that its optical axis is along the axial direction of the insertion portion 3. The imaging sensor 7 a is provided in the insertion portion 3 so as to face the objective lens 7 b near the tip inside the insertion portion 3. The imaging sensor 7 a is connected to the distal end portion of the transmission cable 5. A video scope is configured by the transmission cable 5 and the imaging unit 7, but a fiber scope may be employed instead of the video scope. In the case of a fiberscope, as shown in FIG. 1, an optical fiber bundle (a bundle of a plurality of optical fibers) instead of the transmission cable 5 extends in the axial direction of the insertion portion 3 inside the insertion portion 3 and the operation portion 2. Then, instead of the image sensor, the tip surface of the optical fiber bundle faces the objective lens 7b near the tip inside the insertion portion 3. In the case of a fiberscope, the combination of the tip of the optical fiber bundle and the objective lens 7b corresponds to the imaging unit.

  As shown in FIG. 1, the second illumination unit 8 is provided at the distal end portion 3 a of the insertion portion 3 and illuminates the tip of the distal end surface 3 b of the insertion portion 3. As shown in FIG. 2, the second illumination unit 8 includes a light emitting element (for example, a light emitting diode or an electroluminescence element) 8 a and an illumination lens 8 b. The illumination lens 8b is attached to the distal end surface 3b of the insertion section 3, and the optical axis of the illumination lens 8b is parallel to or inclined with respect to the axial direction of the insertion section 3. The light emitting element 8 a is provided in the insertion portion 3 so as to face the illumination lens 8 b near the tip inside the insertion portion 3. The light emitting element 8a is connected to a lead wire. When electric power is supplied to the light emitting element 8a through the lead wire, the light emitting element 8a emits light, and the light emitted from the light emitting element 8a is emitted from the distal end surface of the insertion portion 3 by the illumination lens 8b. Projected 3b ahead. The light emitted from the light emitting element 8a is visible light, specifically, white light. The lead wire extends in the axial direction of the insertion portion 3 inside the transmission cable 5 or inside the insertion portion 3. Note that a light source device and a light guide may be employed instead of the lead wire and the light emitting element 8a. In that case, the light guide extends in the axial direction of the insertion portion 3 inside the transmission cable 5 or inside the insertion portion 3, and the tip surface of the light guide faces the illumination lens 8 b near the tip inside the insertion portion 3. The base end portion of the light guide is connected to the light source device. The light source device is installed outside the insertion portion 3 and around the insertion portion 3, and visible light (preferably white light) emitted from the light source device is guided to the distal end portion 3a of the insertion portion 3 by a light guide. Then, the light emitted from the distal end surface of the light guide is projected toward the distal end surface 3b of the insertion portion 3 by the illumination lens 8b.

  The channel 4 is a hollow formed inside the insertion portion 3. The channel 4 extends in the axial direction of the insertion portion 3 inside the insertion portion 3. When the insertion part 3 is a tubular member, the channel 4 is hollow in the tube. When the insertion portion 3 has a double tube structure, the hollow of the inner tube is the channel 4. The channel 4 may be a hollow of the insertion portion 3 in which the transmission cable 5 is inserted, or may be a hollow different from the hollow of the insertion portion 3 in which the transmission cable 5 is inserted. When a hollow other than the hollow of the insertion portion 3 in which the transmission cable 5 is inserted is a channel 4, the channel 4 may be a forceps channel.

  One end 4a in the extending direction of the channel 4 opens at the distal end surface 3b of the insertion portion 3, the other end 4b in the extending direction of the channel 4 opens at the outer surface of the operating portion 2, and the channel 4 communicates with both the openings 4a and 4b. ing.

  As shown in FIG.1 and FIG.2, the 1st illumination part 20 is provided in the shape of a cable. Specifically, the 1st illumination part 20 has the cable part 20b and the front-end | tip part 20a, and the front-end | tip part 20a is provided in the front-end | tip of the cable part 20b.

  The first illumination unit 20 extends forward from the distal end surface 3 b of the insertion unit 3 and irradiates light from the distal end 20 a of the first illumination unit 20. Specifically, the first illumination unit 20 is inserted in the channel 4 and extends in the longitudinal direction of the insertion unit 3 along the channel 4. Then, a portion closer to the tip of the first illuminating unit 20 protrudes from the opening 4a of the channel 4 to the tip of the tip surface 3b of the insertion unit 3, and the tip 20a of the first illuminating unit 20 points away from the tip surface 3b of the insertion unit 3. Away. When the channel 4 is a forceps channel, the diameter of the first illumination unit 20 is not particularly limited, but is smaller than 2.8 mm, more preferably 2.6 mm or less.

  As shown in FIG. 2, the first illuminating unit 20 irradiates light from the distal end portion 20a to the side (radially outward) and rearward in the extending direction (axial direction), and preferably further to the front in the extending direction. Irradiate. By irradiating light sideward and rearward in the extending direction from the distal end portion of the first illuminating unit 20, a shadow of a portion of the wall of the body cavity 99 closer to the distal end surface 3b of the insertion portion 3 than to the distal end portion 20a. It is formed to extend rearward in the extending direction. Therefore, when the illumination of the second illumination unit 8 and the illumination of the first illumination unit 20 are compared, the wall of the body cavity 99 looks different. Therefore, the oversight of the lesion on the wall of the body cavity 99 can be prevented.

  It is preferable that the position of the imaging unit 7 is out of the illumination range of the distal end portion 20 a of the first illumination unit 20. The direct light emitted from the distal end portion 20a of the first illumination unit 20 does not enter the imaging unit 7, and the intensity of the light incident on the imaging unit 7 tends to be less than the maximum value of the dynamic range (latitude) of the imaging unit 7. So-called whiteout can be prevented.

  If the position of the imaging unit 7 is within the illumination range of the distal end 20a of the first illumination unit 20, the position of the distal end 20a of the first illumination unit 20 is within the range of the angle of view of the imaging unit 7 as will be described later. It would be nice if you were off. Alternatively, the distal end portion 20a of the first illumination unit 20 is set so that the intensity of light directly incident on the imaging unit 7 from the distal end portion 20a of the first illumination unit 20 is equal to or less than the maximum value of the dynamic range (latitude) of the imaging unit 7. It is good if the light distribution characteristics are designed.

  It is preferable that the position of the distal end portion 20 a of the first illumination unit 20 is out of the range of the angle of view of the imaging unit 7. If it does so, the direct light emitted from the front-end | tip part 20a of the 1st illumination part 20 will not inject into the imaging part 7, but what is called a whiteout can be prevented.

  If the position of the distal end portion 20a of the first illumination unit 20 is within the range of the angle of view of the imaging unit 7, the position of the imaging unit 7 is the illumination range of the distal end portion 20a of the first illumination unit 20 as described above. It would be nice if you were off. Alternatively, the distal end portion 20a of the first illumination unit 20 is set so that the intensity of light directly incident on the imaging unit 7 from the distal end portion 20a of the first illumination unit 20 is equal to or less than the maximum value of the dynamic range (latitude) of the imaging unit 7. It is good if the light distribution characteristics are designed.

For example, as illustrated in FIG. 3, the extending direction of the first illumination unit 20 is parallel to the optical axis Ax of the imaging unit 7 and extends from the distal end surface 3 b of the insertion unit 3 to the distal end 20 a of the first illumination unit 20. The distance is a, the distance from the optical axis Ax of the imaging unit 7 to the center line of the first illumination unit 20 is b, and the tip 20a of the first illumination unit 20 is within the range of the angle of view θ1 of the imaging unit 7. Suppose that In that case, it is preferable that the maximum irradiation angle θmax of the first illumination unit 20 from the direction orthogonal to the center line of the first illumination unit 20 to the rear is less than tan ⁻¹ (b / a). For example, when a = 2 [mm], b = 4 [mm], and θ1 = 140 [deg], the maximum irradiation angle θmax is preferably less than 63.4 [deg]. For example, when a = 6 [mm], b = 4 [mm], and θ1 = 140 [deg], the maximum irradiation angle θmax is preferably less than 33.7 [deg].

  Further, the light emitted from the tip portion 20a of the first illumination unit 20 may be diffused light with low directivity. Then, so-called whiteout can be prevented.

  As shown in FIG. 4, the 1st illumination part 20 may have the shade 20d of a flange type (saddle type). The shade 20d is provided so as to protrude radially outward from the outer peripheral surface of the cable portion 20b of the first lighting unit 20. The shade 20d may be provided over the entire circumference of the cable portion 20b, or may be provided so as to surround a part of the periphery of the cable portion 20b. The position of the shade 20 d is closer to the proximal end than the distal end portion 20 a of the first illumination unit 20 and is further forward than the distal end surface 3 b of the insertion portion 3. Since the shade 20d is formed closer to the base end than the distal end portion 20a, a part of the light projected rearward from the distal end portion 20a in the extending direction is shielded by the shade 20d. Therefore, the direct light emitted from the front end 20a of the first illumination unit 20 does not enter the imaging unit 7, and so-called whiteout can be prevented.

  As shown in FIG. 1, the light source device 30 of the first illumination unit 20 is installed outside the insertion unit 3 and around the insertion unit 3. The light source device 30 emits visible light (preferably white light). For example, the light source device 30 is a xenon light source or a halogen light source.

  A portion near the base end of the first illumination unit 20 is extended from the opening 4 b of the channel 4, and a base end portion of the first illumination unit 20 is connected to the light source device 30. The first illumination unit 20 is a light guide. That is, the first illumination unit 20 captures visible light emitted from the light source device 30 at the base end, guides the captured visible light to the distal end 20a, and projects the guided visible light from the distal end 20a. .

  The first illumination unit 20 may not be a light guide. In that case, the 1st illumination part 20 has a light emitting element (for example, light emitting diode, electroluminescent element) and a lead wire, a light emitting element is incorporated in the front-end | tip part 20a of the 1st illumination part 20, and a lead wire is 1st illumination. Inside the part 20, it extends in the longitudinal direction of the first illumination part 20, and a lead wire is connected to the light emitting element. In that case, the light source device 30 may be omitted. If the first illumination unit 20 uses a light emitting element instead of a light guide, cost reduction can be achieved.

  When the first illumination unit 20 and the second illumination unit 8 are both light guides, the light source device 30 of the first illumination unit 20 is also used as the light source device of the second illumination unit 8. Therefore, cost reduction can be achieved.

  The first lighting unit 20 may not be fixed to the insertion unit 3. If the 1st illumination part 20 is not being fixed to the insertion part 3, by projecting the 1st illumination part 20 to the axial direction along the channel 4, it protruded from the front end surface 3b of the insertion part 3 to the front-end | tip part 20a. The distance can be adjusted.

  Then, the specific example of the 1st illumination part 20 is demonstrated.

[Specific configuration 1 of the first illumination unit]
FIG. 5 is a cross-sectional view of the first illuminating unit 20 mainly showing the distal end portion 20 a of the first illuminating unit 20. As shown in FIG. 5, the cable portion 20b of the first illumination unit 20 includes a tube 21 and a plurality of optical fibers 22, and the distal end portion 20a of the first illumination unit 20 includes the distal end portion of the optical fiber 22, the holder 23, and A hood 24 is provided.

  The tube 21 is a flexible tube. The tube 21 is passed through the channel 4 (see FIG. 1) and extends in the longitudinal direction of the insertion portion 3 along the channel 4. The distal end portion of the tube 21 extends from the distal end opening of the channel 4.

  The optical fiber 22 is passed through the tube 21 and extends along the tube 21 in the axial direction. The optical fibers 22 are arranged in parallel in the circumferential direction with a predetermined interval therebetween. As for the material of the optical fiber 22, any of multi-component glass, quartz glass, and plastic may be selected according to the usage of transparency and color. In addition, the degree of the amount of light transmitted through the optical fiber 22 may be selected from the diameter, numerical aperture NA, and number of the optical fiber 22 within a range that can be mounted inside the tube 21.

  The hood 24 is provided in a cylindrical shape. The hood 24 is made of a transparent material that allows light to pass through. The hood 24 protrudes from the distal end opening of the channel 4 toward the distal end surface 3 b of the insertion portion 3. Note that minute irregularities may be formed on the outer peripheral surface of the hood 24, or a large number of minute cavities or fine particles may be dispersed inside the hood 24. Then, light passing from the hollow of the hood 24 to the outside or from the outside to the hollow of the hood 24 is diffused by the hood 24.

  The hood 24 is attached to the tip of the tube 21 so as to extend from the tip of the tube 21, and the hood 24 and the tube 21 are arranged concentrically. Specifically, the holder 23 is fitted into the distal end opening of the tube 21, and the holder 23 protrudes forward from the tube 21 and is fitted into the hood 24, whereby the tube 21 and the hood 24 are fixed.

  A portion near the tip of the optical fiber 22 penetrates the holder 23 in the axial direction. The distal end portion 22 a of the optical fiber 22 extends forward from the distal end surface of the holder 23 and is accommodated in the hood 24, but the distal end portion 22 a of the optical fiber 22 does not protrude out of the hood 24 from the distal end opening of the hood 24. In the hood 24, the front end portions 22a of the optical fibers 22 are juxtaposed in the circumferential direction with a predetermined interval therebetween. The optical axis of the front end surface (outgoing surface) 22b of the optical fiber 22 is parallel to the axial direction of the hood 24 and the tube 21, and the front end surface 22b of the optical fiber 22 faces the front side in the axial direction. In addition, if the front-end | tip parts 22a of the optical fiber 22 are arranged in parallel at equal intervals, since light is irradiated with respect to the perimeter direction of the hood 24, the light distribution which becomes uniform illumination intensity can be obtained.

  The proximal end portion of the optical fiber 22 is connected to a light source device 30 (shown in FIG. 1). When the light source device 30 is turned on, light emitted from the light source device 30 is taken into the optical fiber 22 by the proximal end surface of the optical fiber 22. The light taken into the optical fiber 22 is guided by the optical fiber 22 to the front end surface 22 b of the optical fiber 22. The light guided to the distal end surface 22 b of the optical fiber 22 is emitted by the distal end surface 22 b of the optical fiber 22. A part of the light emitted from the front end surface 22 b of the optical fiber 22 is emitted from the front end opening of the hood 24 without entering the hood 24. A part of the light emitted from the front end surface of the optical fiber 22 enters the inner surface of the hood 24, passes through the hood 24, and is emitted radially outward from the outer peripheral surface of the hood 24. If the hood 24 allows light to pass therethrough, the irradiation range of the light transmitted through the hood 24 is based on the numerical aperture NA of the optical fiber 22. On the other hand, if the hood 24 is diffusely transmissive due to the internal microcavities or fine particles or the micro unevenness on the outer peripheral surface, the illumination range by the light transmitted through the hood 24 is widened, and the entire periphery of the hood 24 is illuminated.

[Specific configuration 2 of the first illumination unit]
FIG. 6 is a cross-sectional view of the first illuminating unit 20 mainly showing the distal end portion 20 a of the first illuminating unit 20. Parts corresponding to each other between FIGS. 6 and 5 are denoted by the same reference numerals.

  As shown in FIG. 6, the distal end portion 22 a of the optical fiber 22 is curved radially outward with respect to the axial direction of the hood 24, and the optical axis of the distal end surface 22 b of the optical fiber 22 is relative to the axial direction of the hood 24 and the tube 21. And inclined radially outward. The optical axis at the distal end surface 22 b of the optical fiber 22 may be orthogonal to the axial direction of the hood 24 or the tube 21. When the optical axis at the distal end surface 22b of the optical fiber 22 is orthogonal to the axial direction of the hood 24 or the tube 21, the directivity of light from the distal end portion 20a of the first illumination unit 20 to the side in the extending direction is increased. It becomes higher than the directivity of the light from the front-end | tip part 20a of the 1st illumination part 20 to an extension direction.

  Since the distal end surface 22b of the optical fiber 22 faces radially outward in the axial direction of the hood 24, the illumination range of the distal end portion 20a of the first illumination unit 20 in FIG. 6 is rearward in the axial direction than the illumination range in FIG. To spread. That is, the intensity of light that passes through the hood 24 and is emitted in the radial direction from the outer peripheral surface of the hood 24 increases.

  What is necessary is just to adjust suitably the angle of the optical axis in the front end surface 22b of the optical fiber 22, and the axis | shaft of the hood 24 or the tube 21, and the space | interval of the front-end | tip part 22a of the optical fiber 22 according to NA and the diameter of the optical fiber 22.

  Except for what has been described above, portions corresponding to each other between FIG. 6 and FIG. 5 are similarly provided.

[Specific configuration 3 of the first illumination unit]
FIG. 7 is a cross-sectional view of the first illumination unit 20 mainly showing the tip 20a of the first illumination unit 20. As shown in FIG. Parts corresponding to each other between FIGS. 7 and 6 are denoted by the same reference numerals.

  As shown in FIG. 7, a plurality of grooves 24 a are formed on the outer peripheral surface of the hood 24. These grooves 24a are parallel to each other and extend in the circumferential direction. Therefore, protrusions 24b are formed between the grooves 24a, and these protrusions 24b are parallel to each other and extend in the circumferential direction. Since the grooves 24 a and the protrusions 24 b are formed on the outer peripheral surface of the hood 24, light transmitted through the hood 24 and emitted from the outer peripheral surface of the hood 24 is diffused. Therefore, the directivity in the optical axis direction of the optical fiber 22 is lowered, and the light irradiated from the distal end portion 20a of the first illuminating unit 20 to the side (radially outward) in the extending direction (axial direction) and rearward. Strength becomes stronger. There may be a single groove 24a or protrusion 24b. When the groove 24a is singular, the protrusion 24b is not formed, and when the protrusion 24b is singular, the groove 24a is not formed.

  Except for what has been described above, portions corresponding to each other between FIG. 7 and FIG. 6 are similarly provided. In the structure shown in FIG. 5, the groove 24 a and the protrusion 24 b may be formed on the outer peripheral surface of the hood 24.

[Specific configuration 4 of the first illumination unit]
FIG. 8 is a cross-sectional view of the first illumination unit 20 mainly showing the tip 20a of the first illumination unit 20. As shown in FIG. Parts corresponding to each other between FIGS. 8 and 5 are denoted by the same reference numerals.

  As shown in FIG. 8, the distal end portion 20 a of the first illumination unit 20 further includes a reflecting member 25 that reflects light emitted from the distal end surface 22 b of the optical fiber 22 outward in the radial direction with respect to the axial direction of the hood 24. The reflecting member 25 is shaped like a cone, particularly a cone, and the axis of the reflecting member 25 and the axis of the hood 24 overlap, and the top of the reflecting member 25 faces the proximal end side. A specular reflection surface 25 a is formed on the weight surface that is the peripheral surface of the reflection member 25.

  The light emitted from the front end surface 22b of the optical fiber 22 is reflected radially outward by the specular reflection surface 25a, and the light reflected by the specular reflection surface 25a passes through the hood 24 and is radially outward from the outer peripheral surface of the hood 24. Is emitted in the direction. Therefore, the intensity of light emitted from the distal end portion 20a of the first illumination unit 20 to the side (in the radial direction) in the extending direction (outward in the radial direction) and rearward is further increased.

  Although the reflection surface formed on the weight surface of the reflection member 25 is the specular reflection surface 25a, even if the reflection surface is a diffuse reflection surface by performing a diffuse reflection process such as a micro uneven process. Good.

  Except for what has been described above, portions corresponding to each other between FIGS. 8 and 5 are similarly provided. Similarly to the structure shown in FIG. 7, the groove 24 a and the protrusion 24 b may be formed on the outer peripheral surface of the hood 24 in the structure shown in FIG. 8.

[Specific configuration 5 of the first illumination unit]
FIG. 9 is a cross-sectional view of the first illumination unit 20 mainly showing the tip 20a of the first illumination unit 20. As shown in FIG. Portions corresponding to each other between FIG. 9 and FIG.

  As shown in FIG. 9, the distal end portion 20 a of the first illumination unit 20 further includes a plurality of diffusion units 26 that diffuse light emitted from the distal end surface 22 b of the optical fiber 22. The diffusing unit 26 is provided at the distal end portion 22 a of the optical fiber 22 so as to wrap the distal end surface 22 b of the optical fiber 22. The diffusing section 26 may be a transparent base material in which a large number of micro cavities or fine particles are dispersed, or a fiber material formed into a pellet-like lump. Since the light emitted from the front end surface of the optical fiber 22 is diffused in all directions by the diffusion unit 26, the directivity in the optical axis direction of the optical fiber 22 is reduced, and the extending direction from the front end 20a of the first illumination unit 20 The intensity of light irradiated to the side (in the radial direction) and the rear side in the (axial direction) becomes stronger.

  Except for what has been described above, portions corresponding to each other between FIG. 9 and FIG. 5 are similarly provided. Similarly to the structure shown in FIG. 9, even in the structure shown in FIGS. 6, 7, and 8, the diffusing portion 26 may be provided at the distal end portion 22 a of the optical fiber 22 so as to wrap the distal end surface 22 b of the optical fiber 22. Good.

[Specific configuration 6 of the first illumination unit]
FIG. 10 is a cross-sectional view of the first illumination unit 20 mainly showing the tip 20a of the first illumination unit 20. As shown in FIG. Parts corresponding to each other between FIGS. 10 and 5 are denoted by the same reference numerals.

  In addition to the optical fiber 22 that guides visible light, a light projecting optical fiber 27 and a light receiving optical fiber 28 are passed through the tube 21 from the base end portion to the tip end portion of the tube 21, and the light projecting optical fiber 27 and the light receiving optical fiber 28. A front end portion and an optical system (for example, a lens) 29 are fixed to the holder 23, and the optical system (for example, a lens) 29 faces the front end surfaces of the light projecting optical fiber 27 and the light receiving optical fiber 28. The optical system 29 may be disposed in the tube 21, may be disposed in the hood 24, or may be disposed in a boundary portion between the tube 21 and the hood 24.

  The base end of the light projecting optical fiber 27 is connected to a light source device that emits excitation light (for example, ultraviolet light) other than visible light, and the base end of the light receiving optical fiber 28 is connected to a spectroscope. When the light source device for excitation light is turned on, the excitation light is emitted from the distal end surface of the optical fiber for projection 27 and is projected onto the wall of the body cavity outside the hood 24 by the optical system 29. The body cavity wall emits fluorescence or Raman light due to the excitation light, and the light is projected onto the distal end surface of the light receiving optical fiber 28 by the optical system 29, and the spectral data of the light is measured by the spectroscope. Thereby, the biological characteristics of the wall of the body cavity, the progress of the lesion, and the like can be analyzed.

  Except for what has been described above, portions corresponding to each other between FIG. 10 and FIG. 5 are similarly provided. Similarly to the structure shown in FIG. 10, the light projecting optical fiber 27, the light receiving optical fiber 28, and the optical system 29 may be provided in the structures shown in FIGS. 6, 7, 8, and 9.

<Modification>
In the structure shown in FIGS. 5 to 10, the first illumination unit 20 is a light guide, but the first illumination unit 20 may have a light emitting element (for example, a light emitting diode or an electroluminescence element). That is, the lead wire is passed through the tube 21 instead of the optical fiber 22, and the light emitting element is connected to the tip of the lead wire and fixed in the hood 24. The optical axis of the light emitting element (virtual line extending from the light emitting element in the direction in which the luminous intensity becomes maximum) may be parallel to the axis of the hood 24, or may be inclined or orthogonal to the axis. . The optical axis of the light emitting element may be rearward in the axial direction of the hood 24 in a state where the optical axis is inclined with respect to the axis of the hood 24. The light emitting element emits visible light. When the light emitting source of the light emitting element emits excitation light such as ultraviolet rays, the light emitting source of the light emitting element is covered with a fluorescent material, and the fluorescent material emits visible light (fluorescence) by the excitation light emitted from the light emitting source of the light emitting element.

DESCRIPTION OF SYMBOLS 1 Endoscope 3 Insertion part 3a Insertion part tip part 3b Insertion part tip surface 7 Imaging part 20 Illumination part 20a Illumination part tip part 21 Tube 22 Optical fiber 22a Optical fiber tip part 22b Optical fiber tip surface 24 Hood 24a Groove 24b Projection 25 Reflecting member 26 Diffusing portion 27 Optical fiber for light projection 28 Optical fiber for light reception 29 Optical system 30 Light source device

Claims (1)

An elongated insertion part that can be inserted into a body cavity;
An imaging unit provided at a distal end of the insertion unit;
A first illuminating portion that extends forward from the distal end surface of the insertion portion, and irradiates light laterally and rearward in the extending direction from the distal end portion of the insertion portion;
A second illuminating part that is provided at the distal end of the insertion part and illuminates the tip of the distal end surface of the insertion part;
Wherein the first illumination unit may have a shade that blocks a portion of the extending direction of the light emitted backward from the front end portion of the first illumination unit,
The shade protrudes radially outward from the outer peripheral surface of the first illumination part, and the shade is located closer to the proximal end than the distal end part of the first illumination part and ahead of the distal end face of the insertion part. And
The first illumination unit is
A tube extending in the longitudinal direction of the insertion portion inside the insertion portion;
A hood attached to the distal end of the tube and protruding forward from the distal end surface of the insertion portion;
An optical fiber passed through the tube and having a distal end portion disposed in the hood;
The hood passes through or diffuses and transmits light emitted from the front end surface of the optical fiber,
The first illumination unit is
A light emitting optical fiber and a light receiving optical fiber passed through the tube;
An endoscope characterized further having a Rukoto a, an optical system provided in the tube or the hood so as to face the front end surface of the light projecting optical fiber and the light receiving optical fibers.

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