JP3869535B2 - Endoscope - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an endoscope used for medical use, industrial use, and the like.
[0002]
[Prior art]
In the medical field, endoscopes are used for examination and diagnosis of the digestive tract and the like. The endoscope is installed on the proximal end side of the endoscope main body including the light guide optical fiber bundle and the image guide optical fiber bundle, and is used for illumination that illuminates through the light guide optical fiber bundle. It has a light source and a monitor device that is installed on the proximal end side of the endoscope body and monitors a subject image observed through the optical fiber bundle for image guide.
[0003]
In addition, a cylindrical shooting distance holder may be installed at the distal end of the endoscope body. By bringing the distal end of the photographing distance holder into contact with a subject such as the inner wall of the digestive tract, for example, the distance from the subject can be kept constant or the positional relationship with the subject can be fixed.
[0004]
In particular, in variable magnification endoscopes, switching between normal observation with a wide angle and a long observation distance and enlarged observation with a narrow angle and a short observation distance (continuous, bifocal type, etc.) is used. It is necessary to keep the distance to the subject (about 2 to 4 mm) constant. In this case, if the enlargement magnification is high, it is difficult to capture the object even with a slight movement, and the observation image is blurred. Therefore, it is important to fix the distal end portion of the endoscope with the photographing distance holder.
[0005]
In addition, it is necessary to fix the positional relationship between the distal end portion of the endoscope main body and the subject also when performing treatments, cytological examinations, and the like. In these cases, an imaging distance holder is also used. .
[0006]
When observing a subject with such an endoscope, illumination light from an illumination light source passes through a light guide optical fiber bundle and is irradiated onto the subject via an illumination optical system.
[0007]
However, only a limited amount of illumination light can be introduced, and since observation is performed in a wide angle region, illumination unevenness occurs in the observation field (particularly, the amount of light is insufficient at the edge of the observation field). There is a disadvantage that it may interfere with good observation of the subject. This uneven illumination is particularly problematic when performing processing such as photography, treatment, and cell inspection.
[0008]
[Problems to be solved by the invention]
An object of the present invention is to provide an endoscope capable of obtaining a more appropriate observation image by preventing illumination unevenness in the observation visual field.
[0009]
[Means for Solving the Problems]
Such an object is achieved by the present inventions (1) to (6) below.
[0010]
(1) An endoscope having an endoscope body that receives reflected light from an observation site illuminated by illumination light from a light guide optical fiber bundle and obtains an image of the observation site,
An endoscope characterized in that at least the distal end of the endoscope body has a high reflectivity enough to assist illumination of the observation site by reflection of illumination light at the distal end.
[0011]
(2) having a cylindrical photographing distance holder attached to the distal end of the endoscope body;
The endoscope according to (1), wherein at least an inner peripheral surface of the photographing distance holder has a high reflectance enough to assist illumination of the observation site by reflection of illumination light at the site.
[0012]
(3) The endoscope according to (2), wherein an outer peripheral surface of the endoscope main body and an outer peripheral surface of the photographing distance holder form a continuous surface without a step.
[0013]
(4) The endoscope according to (2) or (3), wherein at least an outer peripheral surface and a tip of the photographing distance holder are made of a soft material.
[0014]
(5) The endoscope according to any one of (2) to (4), wherein the photographing distance holder is detachable from the endoscope body.
[0015]
(6) The endoscope according to any one of (1) to (5), wherein the reflectance of the illumination light at the high reflectance portion is 10% or more.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an endoscope of the present invention will be described in detail based on a preferred embodiment shown in the accompanying drawings.
[0017]
FIG. 1 is an overall view showing a first embodiment of an endoscope (direct view type) according to the present invention, FIG. 2 is a side view showing a configuration of a distal end portion of the endoscope shown in FIG. 1, and FIG. The figure which shows reflection of the illumination light in the front-end | tip part of the endoscope shown in FIG. 1, FIG. 4 is an AA arrow directional view in FIG.
[0018]
As shown in these drawings, an endoscope 1 according to the present invention is installed on a long-sided endoscope body 2 having flexibility (flexibility) and a proximal end side of the endoscope body 2. An operation unit 4 and an imaging distance holder (hood) 3 installed at the distal end portion 22 of the endoscope body 2 are provided.
[0019]
As shown in FIG. 1, the endoscope body 2 has a bending portion 21 that can be bent (bent) on the distal end side thereof. A distal end portion 22 is formed at the distal end of the curved portion 21.
[0020]
As shown in FIG. 4, the distal end portion 22 includes an observation optical system (objective optical system) 5 and a pair of illumination optical systems 6 and 6, respectively. The observation optical system 5 and the illumination optical system 6 constitute an endoscope optical system.
[0021]
The endoscope main body 2 incorporates a light guide optical fiber bundle and an image guide optical fiber bundle. The light guide optical fiber bundle is arranged from the base end side of the illumination optical system 6 toward the operation unit 4 side, and the image guide optical fiber bundle is arranged from the base end side of the observation optical system 5 toward the operation unit 4 side. Has been. An image of the observation site (subject) is formed on the incident end face of the optical fiber bundle for image guide via the observation optical system 5.
[0022]
Further, the endoscope body 2 is formed with a channel (lumen) 23 through which a treatment tool such as a forceps or a YAG laser treatment tool is inserted, and an air / water supply port 24 for cleaning.
[0023]
The channel 23, the air / water supply port 24, the optical fiber bundle for image guide, the optical fiber bundle for light guide, the observation optical system 5 and the illumination optical system 6 are arranged at positions decentered from the central axis of the endoscope body 2. Has been. In this case, the illumination optical system 6 is located in the vicinity of the observation optical system 5 and on both the left and right sides of the observation optical system 5 in FIG.
[0024]
Further, a light shielding portion 225 is formed on the outer peripheral portion (edge portion) of the observation optical system 5 on the distal end surface (tip end) 224 of the endoscope body 2.
[0025]
The light shielding portion 225 is provided to shield light incident from the outer peripheral portion of the first surface of the observation optical system 5 and is formed by applying an adhesive mixed with carbon powder on the outer peripheral portion. Has been.
[0026]
As shown in FIG. 1, the operation unit 4 includes an operation unit main body 41 and an operation unit cover 42 that form the outer wall thereof, and a bending operation mechanism for remotely bending the bending unit 21 (bending operation). Has been. A bending operation lever 43 for performing the bending operation is rotatably supported on the operation unit main body 41.
[0027]
An endoscope capable of zooming (zooming endoscope) is provided with a zooming operation lever (not shown) having a configuration substantially similar to that of the bending operation lever 43, and the zooming control lever is operated. It is possible to change the magnification.
[0028]
An eyepiece 7 projects from the head of the operation unit main body 41. The eyepiece 7 can be detachably connected to a camera box (not shown). In this camera box, a camera unit (imaging unit) (not shown) including a CCD (imaging device), an imaging optical system, and the like is housed.
[0029]
The camera unit is connected to a monitor device (not shown) that monitors the image of the observation site imaged by the camera unit.
[0030]
Further, a flexible connecting tube 8 through which the light guide optical fiber bundle is inserted is connected to the side of the operation unit main body 41 opposite to the support portion of the bending operation lever 43. A connector 9 connected to a light source device (not shown) is connected to the tip of the connecting tube 8.
[0031]
As shown in FIGS. 2, 3, and 4, a cylindrical photographing distance holder 3 is detachably attached to the distal end portion 22 of the endoscope body 2.
[0032]
By bringing the distal end of the photographing distance holder 3 into contact with the observation site, the distance from the observation site can be kept constant or the positional relationship with the observation site can be fixed.
[0033]
The photographing distance holder 3 has a high reflectivity that can assist the illumination of the observation site by the reflection of the illumination light on the inner peripheral surface 31, that is, a high reflectivity that can function as secondary illumination (hereinafter referred to as “secondary illumination”). It is simply called “high reflectivity”).
[0034]
Specifically, the reflectance of the illumination light of the photographing distance holder 3, that is, the reflectance of the illumination light on the inner peripheral surface 31 of the photographing distance holder 3 (the reflectance of the illumination light of the part having a high reflectance) is It is set higher than that of the light shielding unit 225.
[0035]
In addition, the light-shielding part 225 is comprised with carbon powder etc. as mentioned above, and the reflectance is about several percent.
[0036]
The reflectance of the inner peripheral surface 31 of the photographing distance holder 3 is preferably 10% or more, more preferably 30% or more, and further preferably about 50 to 80%.
[0037]
By setting the reflectance of the inner peripheral surface 31 of the photographing distance holder 3 to 10% or more, more uniform illumination can be performed.
[0038]
The illumination light is determined by a light source (not shown) of the light source device. As the light source, for example, a xenon light source, a halogen light source, or the like can be used.
In addition, when illumination light is visible light, white light may be sufficient and monochromatic light may be sufficient.
[0039]
The diameter of the photographing distance holder 3 is preferably constant or gradually decreasing (tapering) toward the tip.
[0040]
The constituent material of the photographing distance holder 3 is not particularly limited as long as the inner peripheral surface 31 of the photographing distance holder 3 can have a high reflectivity. For example, a metal material such as aluminum or titanium, acrylic, or the like can be used. Hard resins, hard materials such as various ceramics, rubber materials, soft materials such as soft resins, and the like can be used.
[0041]
Among these, from the viewpoint of performing more uniform illumination, a material capable of making the reflectance of the inner peripheral surface 31 of the photographing distance holder 3 higher, for example, a metal material is preferable. However, a soft material is more preferable for the reason of protecting an observation site, particularly a living tissue.
[0042]
FIG. 5 is a partial cross-sectional view showing the distal end portion 22 of the endoscope body 2 and the photographing distance holder 3.
[0043]
In this endoscope 1, the distal end surface (tip) 224 of the endoscope main body 2 is set to have a high reflectivity as in the case of the photographing distance holder 3 described above.
[0044]
Specifically, as shown in FIG. 5, a portion other than the channel 23 at the tip of the endoscope body 2, the air / water supply port 24, the observation optical system 5, the illumination optical system 6, and the light shielding unit 225 is not high. A reflective layer (coating layer) 226 having a reflectance is formed by coating. That is, the distal end surface 224 of the endoscope body 2 is configured by the surface of the coating layer 226.
[0045]
As the coating layer 226, for example, a predetermined coating (for example, white or other light-colored coating) is applied, or a metal material for the photographing distance holder 3 described above is formed by plating, metal vapor deposition, sputtering, or the like. Is mentioned.
[0046]
Further, as shown in FIG. 5, a reduced diameter portion 221 whose outer diameter is reduced is formed on the distal end side of the distal end portion 22 of the endoscope body 2. A male screw (screw) 222 is formed in the reduced diameter portion 221.
[0047]
On the proximal end side of the photographing distance holder 3, a female screw (screw) 32 that is screwed with the male screw 222 is formed.
[0048]
In the endoscope 1, the photographing distance holder 3 is rotated in a predetermined direction and the screws 222 and 32 are screwed together until the end surface 33 of the photographing distance holder 3 comes into contact with the end surface 223 of the distal end portion 22. The photographing distance holder 3 is attached to the distal end portion 22.
[0049]
In addition, the outer diameter of the endoscope main body 2, the outer diameter of the reduced diameter portion 221, such that the outer peripheral surface of the endoscope main body 2 and the outer peripheral surface of the photographing distance holder 3 form a continuous surface without a step, Various conditions such as the outer diameter of the photographing distance holder 3 are set. As a result, it is possible to easily insert the endoscope main body 2 into the target site and to prevent the passage site from being damaged when the endoscope main body 2 is inserted.
[0050]
Further, the tip of the photographing distance holder 3 is rounded. As a result, the endoscope body 2 can be easily inserted, and the passage portion is damaged when the endoscope body 2 is inserted, or the distal end of the photographing distance holder 3 is brought into contact with the observation portion. It is possible to prevent the observation site from being damaged.
[0051]
Next, the operation of the endoscope 1 will be described.
When the photographing distance holder 3 is attached to the distal end portion 22 of the endoscope body 2, the photographing distance holder 3 is moved in a predetermined direction until the end surface 33 of the photographing distance holder 3 comes into contact with the end surface 223 of the distal end portion 22. The screws 222 and 32 are screwed together.
[0052]
When observing the observation site by bringing the distal end of the imaging distance holder 3 into contact with the observation site, the illumination light from the light source device passes through the light guide optical fiber bundle and irradiates the observation site via the illumination optical system 6. Is done.
[0053]
In this case, as shown in FIG. 3, the illumination light from the illumination optical system 6 spreads at a wide angle, and a part of the illumination light (primary illumination light) is reflected by the inner peripheral surface 31, and this reflected light is Illuminate the observation site. Further, part of the illumination light that reaches the observation site and is reflected by the observation site is also reflected by the inner peripheral surface 31 and the tip surface 224, and this reflected light (secondary illumination light) illuminates the observation site ( Secondary lighting).
[0054]
In this way, the inner peripheral surface 31 and the front end surface 224 act like an integrating sphere, that is, a part of the illumination light is reflected once or more than once at the inner peripheral surface 31 or the front end surface 224, thereby observing the observation site. Illumination assists the illumination of the observation site with the primary illumination light, particularly the illumination of the edge of the observation site where the intensity of the primary illumination light is low. As a result, the entire observation site is illuminated uniformly.
[0055]
The reflected light from the observation site passes through the observation optical system 5, passes through the image guide optical fiber bundle, and is guided to the camera unit. The reflected light is guided by the imaging optical system of the camera unit so as to form an image on the light receiving surface of the CCD of the camera unit.
[0056]
The image of the observation site is picked up by the camera unit, and the video is displayed on the monitor device.
[0057]
When the photographing distance holder 3 is removed from the distal end portion 22 of the endoscope body 2, the photographing distance holder 3 is rotated in the opposite direction.
[0058]
When the photographing distance holder 3 is detached from the distal end portion 22 of the endoscope main body 2, a dummy ring (not shown) is used to make the outer diameter of the endoscope main body 2, that is, the outer diameter of the distal end portion 22, constant. Is attached to the tip 22.
[0059]
In addition, when observing an observation site | part with the endoscope 1, it is not restricted to monitoring as an electronic image, You may observe with the naked eye via the eyepiece optical system which the eyepiece part 7 does not illustrate.
[0060]
As described above, according to the endoscope 1, it is possible to uniformly illuminate the entire observation region, that is, the observation field.
[0061]
Therefore, it is possible to prevent a part of the observation image (for example, the edge of the observation image) from being darkened, and to obtain a more appropriate observation image (display a more appropriate image on the monitor device). be able to).
[0062]
In addition, since the photographing distance holder 3 is detachable from the endoscope main body 2, the photographing distance holder 3 and the endoscope main body 2 can be easily and reliably cleaned.
[0063]
Note that the surface of the high-reflectance portion of the endoscope 1 described above may be finished as a mirror surface or a diffusion surface.
[0064]
Next, a second embodiment of the endoscope of the present invention will be described.
FIG. 6 is a partial sectional view showing the distal end portion 22 of the endoscope body 2 and the photographing distance holder 3 in the second embodiment of the endoscope of the present invention. In addition, description is abbreviate | omitted about the common point with the endoscope 1 of 1st Example mentioned above, and a main difference is demonstrated.
[0065]
As shown in the drawing, a reflective layer (coating layer) 35 having a high reflectance is formed on the inner side of the photographing distance holder 3 of the endoscope 1 of the second embodiment. That is, the inner peripheral surface 31 of the photographing distance holder 3 is constituted by the surface of the covering layer 35.
[0066]
As the coating layer 35, for example, a predetermined coating (for example, white or other light-colored coating) is applied, or a metal material of the above-described photographing distance holder 3 is formed by plating, metal vapor deposition, sputtering, or the like. Is mentioned.
[0067]
In the endoscope 1 as well, the inner peripheral surface 31 of the photographing distance holder 3 and the distal end surface 224 of the endoscope main body 2 have high reflectivity as in the endoscope 1 of the first embodiment described above. Therefore, the inside of the observation visual field can be illuminated uniformly, and thus a more appropriate observation image can be obtained.
[0068]
In this embodiment, since the high reflectivity is realized by the covering layer 35, the constituent material of the photographing distance holder 3 is a soft material such as a rubber material or a soft resin for the purpose of protecting the observation site (living body). It is preferable to use materials.
[0069]
In the present invention, the covering layer 35 may be provided on a part of the photographing distance holder 3 in the circumferential direction or the height direction.
[0070]
Next, a third embodiment of the endoscope of the present invention will be described.
FIG. 7 is a partial cross-sectional view showing the distal end portion 22 of the endoscope main body 2 and the photographing distance holder 3 in the third embodiment of the endoscope of the present invention. In addition, description is abbreviate | omitted about the common point with the endoscope 1 of the 1st or 2nd Example mentioned above, and a main difference is demonstrated.
[0071]
As shown in the figure, the photographing distance holder 3 of the endoscope 1 of the third embodiment has a coating layer 34 made of a soft material on the outer surface and the tip.
As the soft material, for example, an elastic material such as a rubber material can be used.
[0072]
In the endoscope 1 as well, the inner peripheral surface 31 of the photographing distance holder 3 and the distal end surface 224 of the endoscope main body 2 have high reflectivity as in the endoscope 1 of the first embodiment described above. Therefore, the inside of the observation visual field can be illuminated uniformly, and thus a more appropriate observation image can be obtained.
[0073]
Moreover, since it has the coating layer 34, when the endoscope body 2 is inserted, the passage site (living body) is damaged, or the distal end of the imaging distance holder 3 is brought into contact with the observation site (living body). It is possible to prevent the observation site from being damaged.
[0074]
Here, when the main part of the shooting distance holder 3 is made of a hard material such as a metal material, hard resin, or ceramics, particularly when it is made of a metal material, the shooting distance is as in this embodiment. A covering layer 34 is preferably formed on the holder 3.
[0075]
Next, a fourth embodiment of the endoscope of the present invention will be described.
FIG. 8 is a view showing the endoscope main body 2 and the photographing distance holder 3 in the fourth embodiment of the endoscope of the present invention (a view taken along the line AA in FIG. 2), and FIG. It is a fragmentary sectional view which shows the front-end | tip part 22 and the imaging | photography distance holder 3 of the endoscope main body 2 in 4th Example of the endoscope of invention. In addition, description is abbreviate | omitted about the common point with the endoscope 1 of the 1st or 2nd Example mentioned above, and a main difference is demonstrated.
[0076]
As shown in these drawings, the endoscope 1 of the fourth embodiment is provided with a bayonet mount type connecting portion 11 instead of the male screw 222 and the female screw 32 of the endoscope 1 of the first embodiment described above. It has been. Hereinafter, the structure of this connection part 11 is demonstrated.
[0077]
A plurality of L-shaped long holes 111 are formed in the reduced diameter portion 221 of the distal end portion 22 of the endoscope body 2 along the circumferential direction. In this case, the width of the long hole 111 is set larger on the inner peripheral side than on the outer peripheral side of the reduced diameter portion 221.
[0078]
A projection 115 corresponding to each of the long holes 111 is formed on the inner peripheral surface 31 on the proximal end side of the photographing distance holder 3.
[0079]
The protrusion 115 includes a columnar head portion 116 and a columnar shaft portion 117 concentrically formed on the head portion 116. In this case, the diameter of the head portion 116 is set to be larger than the diameter of the shaft portion 117, larger than the width on the outer peripheral side of the long hole 111, and smaller than the width on the inner peripheral side of the long hole 111. That is, the head portion 116 of the protrusion 115 can be inserted into the long hole 111, and the head portion 116 is prevented from coming out of the long hole 111.
[0080]
When the photographing distance holder 3 is attached to the distal end portion 22 of the endoscope body 2, first, each projection 115 of the photographing distance holder 3 is inserted into the corresponding long hole 111, and the photographing distance holder 3 is used as a base. Push in the end side (upper side in FIG. 9). Thereby, the protrusion 115 moves to the base end portion (upper end portion in FIG. 9) of the long hole 111.
[0081]
Next, the photographing distance holder 3 is rotated in a predetermined direction until the projection 115 comes into contact with the inner surface of the deepest portion (right end portion in FIG. 9) of the long hole 111, whereby the photographing distance holder 3 is moved to the distal end portion 22. Attach to.
[0082]
In the endoscope 1 as well, the inner peripheral surface 31 of the photographing distance holder 3 and the distal end surface 224 of the endoscope main body 2 have high reflectivity as in the endoscope 1 of the first embodiment described above. Therefore, the inside of the observation visual field can be illuminated uniformly, and thus a more appropriate observation image can be obtained.
[0083]
Further, since the photographing distance holder 3 is mounted by engaging the projection 115 with the tip portion 22, the photographing distance holder 3 can be attached and detached more easily than the endoscope 1 of the first embodiment described above. be able to.
[0084]
As with the endoscope 1 of the third embodiment described above, the imaging distance holder 3 also has a coating layer 34 made of a soft material on the outer surface and the tip. Also good.
[0085]
Next, a fifth embodiment of the endoscope of the present invention will be described.
FIG. 10 is a partial cross-sectional view showing the distal end portion 22 of the endoscope body 2 and the photographing distance holder 3 in the fifth embodiment of the endoscope of the present invention. In addition, description is abbreviate | omitted about the common point with the endoscope 1 of the 1st or 2nd Example mentioned above, and a main difference is demonstrated.
[0086]
As shown in the figure, in the endoscope 1 of the fifth embodiment, the distal end portion 22 of the endoscope body 2 and the photographing distance holder 3 are integrally formed.
[0087]
In the endoscope 1 as well, the inner peripheral surface 31 of the photographing distance holder 3 and the distal end surface 224 of the endoscope main body 2 have high reflectivity as in the endoscope 1 of the first embodiment described above. Therefore, the inside of the observation visual field can be illuminated uniformly, and thus a more appropriate observation image can be obtained.
In addition, the number of parts is reduced and productivity is improved.
[0088]
As with the endoscope 1 of the third embodiment described above, the endoscope 1 also has an imaging distance holder 3 with a coating made of a soft material on the outer surface and the tip, as shown in FIG. The layer 34 may be included.
[0089]
Next, a sixth embodiment of the endoscope of the present invention will be described.
FIG. 12 is a view (a view taken along line AA in FIG. 2) showing the endoscope body 2 in the sixth embodiment of the endoscope of the present invention. In addition, description is abbreviate | omitted about the common point with the endoscope 1 of the 1st or 2nd Example mentioned above, and a main difference is demonstrated.
[0090]
As shown in the figure, in the endoscope 1 of the sixth embodiment, the photographing distance holder 3 is omitted. The distal end surface 224 of the endoscope main body 2 has a high reflectance.
[0091]
In this endoscope 1 as well, the distal end surface 224 of the endoscope body 2 has a high reflectivity as in the endoscope 1 of the first embodiment described above, so that the observation field of view is illuminated uniformly. Therefore, a more appropriate observation image can be obtained.
[0092]
As mentioned above, although the endoscope of the present invention has been described based on the illustrated embodiments, the present invention is not limited to these, and the configuration of each part is an arbitrary configuration having the same function. Can be replaced.
[0093]
For example, each of the embodiments described above is a fiber endoscope (fiberscope), but the present invention is not limited to this, and an electronic endoscope having a built-in CCD (imaging device) or the like at the distal end portion of the endoscope body. It may be a mirror (video scope).
[0094]
In the present invention, in the case of an endoscope having a detachable shooting distance holder, the shooting distance holder may be configured to be fitted to the distal end portion of the endoscope body.
[0095]
In the present invention, in the case of an endoscope having an imaging distance holder, at least the distal end of the endoscope body and / or at least the inner peripheral surface of the imaging distance holder is an observation site due to reflection of illumination light at the site. It is sufficient that the reflectivity is high enough to assist the illumination.
[0096]
However, from the viewpoint of more uniform illumination, at least the distal end of the endoscope body and at least the inner peripheral surface of the imaging distance holder each assist the illumination of the observation site by reflecting the illumination light at that site. It is preferable that the reflectivity be as high as possible.
[0097]
【The invention's effect】
As described above, according to the endoscope of the present invention, the inside of the observation visual field can be illuminated uniformly, and thus a more appropriate observation image can be obtained.
[Brief description of the drawings]
FIG. 1 is an overall view showing a first embodiment of an endoscope of the present invention.
FIG. 2 is a side view showing a configuration of a distal end portion of the endoscope shown in FIG.
FIG. 3 is a diagram showing reflection of illumination light at the distal end portion of the endoscope shown in FIG. 1;
FIG. 4 is a view taken along the line AA in FIG. 2;
5 is a partial cross-sectional view showing a distal end portion of an endoscope main body and an imaging distance holder of the endoscope shown in FIG. 1. FIG.
FIG. 6 is a partial cross-sectional view showing a distal end portion of an endoscope main body and an imaging distance holder in the second embodiment of the endoscope of the present invention.
FIG. 7 is a partial cross-sectional view showing a distal end portion of an endoscope main body and an imaging distance holder in the third embodiment of the endoscope of the present invention.
FIG. 8 is a view (an AA arrow view in FIG. 2) showing an endoscope main body and an imaging distance holder in the fourth embodiment of the endoscope of the present invention.
FIG. 9 is a partial cross-sectional view showing a distal end portion of an endoscope main body and an imaging distance holder in the fourth embodiment of the endoscope of the present invention.
FIG. 10 is a partial cross-sectional view showing a distal end portion of an endoscope main body and an imaging distance holder in the fifth embodiment of the endoscope of the present invention.
FIG. 11 is a partial cross-sectional view showing a distal end portion of an endoscope main body and an imaging distance holder in the fifth embodiment of the endoscope of the present invention.
12 is a view (a view taken along line AA in FIG. 2) showing an endoscope body in the sixth embodiment of the endoscope of the present invention. FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Endoscope 2 Endoscope main body 21 Bending part 22 Tip part 221 Reduced diameter part 222 Male screw 223 End face 224 End face (tip)
225 Light-shielding part 226 Reflective layer (coating layer)
23 channels (lumen)
24 Air supply / water supply port 3 Shooting distance holder 31 Inner peripheral surface 32 Female thread 33 End surface 34 Cover layer 35 Reflective layer (cover layer)
4 operation unit 41 operation unit main body 42 operation unit cover 43 bending operation lever 5 observation optical system (objective optical system)
6 Illumination optical system 7 Eyepiece 8 Connection tube 9 Connector 11 Connection portion 111 Long hole 115 Protrusion 116 Head 117 Shaft

Claims (6)

An endoscope having an endoscope body that receives reflected light from an observation site illuminated by illumination light from a light guide optical fiber bundle and obtains an image of the observation site,
An endoscope characterized in that at least the distal end of the endoscope body has a high reflectivity enough to assist illumination of the observation site by reflection of illumination light at the distal end. A cylindrical shooting distance holder attached to the distal end of the endoscope body,
The endoscope according to claim 1, wherein at least an inner peripheral surface of the photographing distance holder has a high reflectivity enough to assist illumination of the observation site by reflection of illumination light at the site.   The endoscope according to claim 2, wherein an outer peripheral surface of the endoscope main body and an outer peripheral surface of the photographing distance holder form a continuous surface without a step.   The endoscope according to claim 2 or 3, wherein at least an outer peripheral surface and a tip of the photographing distance holder are made of a soft material.   The endoscope according to any one of claims 2 to 4, wherein the photographing distance holder is detachable from the endoscope body.   The endoscope according to any one of claims 1 to 5, wherein a reflectance of the illumination light at the high reflectance portion is 10% or more.

Images