JP4127794B2 - Endoscope - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an endoscope having an imaging unit and suitable for a small-diameter insertion portion.
[0002]
[Prior art]
In recent years, endoscopes have been widely used in the medical field and the industrial field. Also, recently, endoscopes that incorporate an imaging unit equipped with an imaging element so that an endoscope image obtained by an endoscope can be easily recorded, edited and reused are widely adopted. became.
An image sensor has been developed that is very miniaturized. However, in the case of an endoscope having a small-diameter insertion portion used for the bronchi or the like, the insertion portion is provided at the distal end of the insertion portion. The outer diameter of will become thicker.
[0003]
For this reason, for example, in the conventional example of Japanese Patent Laid-Open No. 11-151200, the image pickup device captures an image within the grip portion where the rear end of the optical fiber for image transmission inserted into the insertion portion inserted into the eyeball portion is arranged. An endoscope that forms an image on a surface is disclosed.
In this conventional example, the optical fiber inserted into the insertion portion is imaged on the image pickup element via the opposing projection lens in a state where the optical fiber is extended substantially linearly in the grip portion.
[0004]
By the way, in a so-called flexible endoscope having a flexible insertion portion or an endoscope having a mechanism capable of bending the distal end portion of the insertion portion even when the insertion portion is rigid, generally, an optical fiber for image transmission is as follows. The design which provided the bending which considered this point is made.
[0005]
・ Prevents optical fibers from being stretched and damaged when the insertion part is bent or when the tip is bent.
[0006]
-Absorbs variations in length of optical fiber and insertion section.
[0007]
・ Avoid channel tubes for suction, air supply, and water supply or wires for bending.
[0008]
-Facilitates handling of optical fibers during assembly.
[0009]
However, in an endoscope in which the end of the optical fiber is fixed in the gripping part that follows the insertion part as in the above-described conventional example, the optical fiber is inserted in the eyepiece part that follows the insertion part, the gripping part, and the (curving) operation part. Compared to a general fiberscope in which the end portion is fixed, the distance from the end of the optical fiber to the end of being fixed after the end of the optical fiber is fixed, the space for absorbing the bending of the optical fiber is reduced. On the other hand, even if the space to absorb the bending of the optical fiber is increased by increasing the inner diameter of the gripping part, it is limited in that it must be made easy to grip because it is a gripping part. Will occur.
[0010]
[Patent Document 1]
Japanese Patent Laid-Open No. 11-151200
[Problems to be solved by the invention]
As described above, a sufficient space for absorbing the amount of bending of the optical fiber cannot be secured, so that it is necessary to suppress variations in the length of the optical fiber as much as possible, and the manufacturing cost of the optical fiber increases. In addition, even if the rear end of the optical fiber, the position of the imaging lens and the image sensor can be set to a state where a clear image can be formed, if the insertion portion is bent because the amount of bending of the optical fiber is insufficient, A large force acts on the fixed part of the rear end of the optical fiber, and therefore the optical fiber is damaged, the durability is easily deteriorated, and the imaging characteristics are also easily deteriorated due to the deterioration of the image transmission function caused by them, In addition, there is a disadvantage that the imaging characteristics are deteriorated even when the rear end of the optical fiber is moved.
[0012]
(Object of invention)
The present invention has been made in view of the above-described points, and provides an endoscope with good assemblability that can ensure the amount of bending of an optical fiber with a simple configuration and can easily maintain a predetermined imaging function. The purpose is to do.
[0013]
[Means for Solving the Problems]
An elongated insert,
A grip portion provided on a proximal end side of the insertion portion, and capable of being gripped by an operator;
An objective optical system provided at the distal end of the insertion portion and capable of transmitting an optical image of a subject into the insertion portion;
The optical image incident from the distal end side through the objective optical system can be transmitted to the proximal end side, and is inserted into the insertion portion so that the proximal end side extends from the insertion portion to the inside of the gripping portion. An image guide fiber bundle,
An optical system emitting portion that is provided on the proximal end side of the image guide fiber bundle and emits the optical image transmitted from the distal end side;
An imaging unit that is optically connected to the optical image emitting unit and capable of imaging an optical image transmitted from the optical image emitting unit;
In an endoscope having
The optical axis of the optical image emitted from the optical image emitting unit toward the imaging unit is shifted with respect to the central axis of the portion where the image guide fiber bundle extends into the gripping unit. By arranging the image pickup unit, the image guide when the insertion portion is bent is formed with a larger deflection portion formed more smoothly in the portion reaching the output end of the image guide fiber bundle than in the case where their axes are coaxial. A predetermined imaging function can be maintained by eliminating or reducing the action of tension on the fiber bundle, or by absorbing the influence of variations in the individual image guide fiber bundles by the bending portion.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
(First embodiment)
1 to 5 relate to the first embodiment of the present invention, FIG. 1 shows the appearance of the endoscope of the first embodiment, FIG. 2 shows the internal configuration of the distal end side of the insertion portion, 3 shows an internal configuration of the operation unit, and FIGS. 4A, 4B, and 4C are enlarged cross-sectional views taken along lines AA, BB, and CC in FIG. 3, respectively. FIG. 5 is an enlarged view of the imaging unit portion of FIG.
[0015]
As shown in FIG. 1, an endoscope 1 according to a first embodiment of the present invention is inserted into a body cavity or the like and is provided with an elongated insertion portion 2 having flexibility and a rear end of the insertion portion 2. And the universal cord 4 whose proximal end (proximal end) extends from the side of the manipulation portion 3 and the connector 5 provided at the end (distal end) of the universal cord 4 The light guide base 6 protrudes from the end of the connector 5, and the light guide base 6 is attached to a light source device (not shown) so that illumination light is supplied from the light source device. It is transmitted by a bundle of light guide fibers inserted into the mirror 1 and emitted from the illumination window at the end (tip) of the insertion portion 2 to illuminate a site to be examined such as an affected area.
[0016]
In addition, an electrical connector portion 7 is provided on the side surface of the connector 5, and the electrical connector portion 7 is attached to the video processor via a connection cable (not shown) attached to the electrical connector portion 7. A video signal is generated by electrically connecting to a solid-state imaging device (described later) built in the endoscope 1, applying a drive signal to the solid-state imaging device, and performing signal processing on the imaging signal captured by the solid-state imaging device. The image output to a monitor (not shown) can be displayed on the display surface of the monitor.
[0017]
The insertion portion 2 is provided with a hard distal end portion 8, a bendable bending portion 9, and a flexible flexible portion 10 in that order from the distal end side, and the rear end of the flexible portion 10 reaches the operation portion 3. .
In addition, the operation unit 3 is provided with a grip 11 on the front end side that an operator or the like grips. A connecting member that is connected to the insertion portion 2 is built in the front end of the grip portion 11.
[0018]
A bending lever 12 is provided on the rear (upper end or top) side of the gripping part 11 so that it can be operated by a hand holding the gripping part 11. By operating the bending lever 12, the bending part 9 is moved up and down. So that the tip 8 can be directed in a desired direction. Further, a video switch unit 13 for remotely controlling freeze and release is provided on the video processor side at the rear end of the operation unit 3.
[0019]
Further, an insertion port 14 for a treatment instrument such as forceps is provided near the front end of the grasping portion 11, and the treatment instrument inserted from the insertion port 14 is in a channel provided in the longitudinal direction of the insertion portion 2. Can be inserted.
[0020]
Further, a light guide fiber bundle (not shown), a signal cable connected to the solid-state imaging device, and the like are inserted into the universal cord 4 extending from the operation unit 3 in a direction orthogonal to the side surface thereof.
[0021]
Next, the configuration of the distal end side of the insertion portion 2 will be described with reference to FIG.
As shown in FIG. 2, the tip 8 is formed of a tip main body 16 in which a hard member such as a metal is formed in a substantially cylindrical shape. The tip main body 16 has a large number of holes in its axial direction. Built-in objects are fixed.
[0022]
For example, an objective lens system (objective optical system) 18 is fixed to a hole of the observation window via a lens frame 17 or the like, and an optical image (observation image) transmission function is provided at the imaging position of the objective lens system 18. The front end surface of the image guide fiber bundle 19 having is fixed. The image guide fiber bundle 19 transmits an optical image formed on the front end face thereof to a rear end face (outgoing end face) disposed near the inside of the operation unit 3.
[0023]
Further, the distal end of the flexible tube 21 forming the channel 20 inserted into the insertion portion 2 is fixed to the rear end of a hole provided adjacent to the observation window via a base member 22. As will be described later, the rear end side of the channel 20 branches halfway, one of which communicates with the insertion port 14, and the other communicates with the suction pipe line extending to the rear end side of the operation unit 3. Further, the tip of the channel 20 is opened through a hole in the tip body 16.
[0024]
In addition, a light guide fiber bundle (not shown) is inserted into the insertion portion 2, and the tip thereof is fixed to the illumination window hole of the tip portion main body 16, and the illumination light is emitted from the fixed tip surface. Then, the object in the observation range of the objective lens system 18 is illuminated.
[0025]
Further, a cutting edge (node ring) 23 having a substantially annular shape is fixed to the rear end of the tip body 16, and the tip of the next bending piece 23 is connected to the rear end of the bending piece 23, for example, left and right A number of bending pieces 23 are rotatably connected in the longitudinal direction of the insertion portion 2 so as to be rotatably connected via a rotation connecting member such as a rivet 24 at a position corresponding to a predetermined direction such as a direction. Thus, a curved portion 9 is formed.
[0026]
Further, a pair of bending wires 25 are inserted along a position corresponding to, for example, the vertical direction, which is separated from the connection position by the rivet 24, and the tip thereof is firmly fixed to the most advanced bending piece 23 by brazing or the like. Yes.
[0027]
The pair of bending wires 25 has their rear ends fixed to a drum (not shown) that forms a bending mechanism inside the operation unit 3, and the drum performs an operation of rotating the bending lever 12, thereby the pair of bending wires 25. One of the two is pulled and the other is relaxed so that the bending portion 9 can be bent toward the bent bending wire 25 side. It should be noted that the bending wire 25 is inserted through the inside of the coil so as to freely advance and retract on the rear end side of the bending portion 9.
As shown in FIG. 2, the bending portion 9 is covered with a netting tube 28 and a bending rubber tube 29 made of an elastic resin that covers the outside thereof.
[0028]
Next, with reference to FIGS. 3 to 5, the internal structure of the grasping portion 11 grasped in the operation portion 3, specifically, the operator on the front end side of the operation portion 3 will be described.
The exterior member of the operation unit 3 includes a gripping unit exterior member 31 that covers the gripping unit 11 on the front end side of the operation unit 3 and an operation unit body exterior member 32 that covers the operation unit body part on the rear end side. The members 31 and 32 are connected to each other through a watertight seal member such as an O-ring 34 at a connecting portion 33 that is fitted to each other.
[0029]
Inside this gripping part exterior member (hereinafter simply abbreviated as exterior member) 31, a substantially plate-shaped frame 35 is disposed as an internal structure for ensuring a predetermined strength inside. One end (rear end) in the longitudinal direction is bent into a substantially L shape, and is fixed to the operation unit main body exterior member 32 with a screw (not shown) inside the connection portion 33, and the other end reaches the vicinity of the front end of the grip portion 11.
[0030]
In the vicinity of the front end of the frame 35, a branch member (not shown) that is branched to the insertion port 14 side and the suction conduit 36 side that is shown in cross section in FIG. The
[0031]
In addition, the rear end of the flexible tube 37 that forms the exterior member of the insertion portion 2 and into which the image guide fiber bundle 19 and the like are inserted into the hollow portion is in the vicinity of the front end of the grip portion 11 via the connecting member 38. 31 is connected.
[0032]
In addition, the vicinity of the boundary between the rear end of the flexible tube 37 and the gripping portion 11 is prevented from being bent sharply by a bend-preventing member 39 that is tapered and thickened to the rear side.
[0033]
The flexible image guide fiber bundle 19 inserted into the insertion portion 2 is inserted along the substantially central axis of the flexible tube 37, and is tapered in the vicinity of the rear end of the insertion portion 2. By the member 39 (in a state where a large bend is suppressed), it extends rearward substantially linearly as indicated by a one-dot chain line C.
[0034]
In the present embodiment, the inner side of the tapered bending preventing member 39 in the vicinity of the rear end of the insertion portion 2 is extended substantially linearly toward the rear gripping portion 11 as indicated by a one-dot chain line C. The image guide fiber bundle 19 has a rear end (base) in a state in which a bending portion (playing portion) 42 is formed on the imaging unit 41 attached in the grip portion 11 shifted from a substantially straight line indicated by the one-dot chain line C. End) is fixed.
[0035]
That is, as shown in FIG. 3, the rear end side of the substantially rectangular frame 35 elongated in the longitudinal direction is cut out from the lateral side perpendicular to the longitudinal direction inside the grip portion 11. A notch 35a is provided, and a substantially cylindrical imaging unit 41 is disposed in the notch 35a. As shown in FIGS. 4 (A) and 4 (B), an L-shape attached to the frame 35 with screws 44a. The imaging unit 41 is fixed (to the frame 35) via the mounting member 45 having a shape.
[0036]
As described above, in the present embodiment, a part of the frame 35 disposed substantially in the center of the gripper 11 is cut away from the side (upper side in FIG. 3), and the center of the gripper 11 in the longitudinal direction. The imaging unit 41 is arranged and fixed in a notch 35a formed at a position shifted from the position.
[0037]
As shown in an enlarged view in FIG. 5, the imaging unit 41 is a substantially cylindrical rigid fiber receiver that holds a hard base 43 made of metal or the like that protects the exit end of the rear end of the image guide fiber bundle 19. 46, a relay optical system 47 that is disposed opposite to the exit end face 19a of the image guide fiber bundle 19 and has a function of forming an optical image transmitted to the exit end face 19a at a desired magnification, and the repeater optical system. An imaging unit 49 provided with, for example, a charge coupled device (abbreviated as CCD) 48 as a solid-state imaging device that is disposed at an imaging position imaged at a predetermined size by the system 47 and has a function of photoelectric conversion; A signal cable 50 extends from the rear end of the imaging unit 49 to the rear side.
[0038]
In the present embodiment, the relay optical system 47 that forms an image with a desired size is used. However, in order to reduce the cost, the optical image transmitted to the rear end surface 19a of the image guide fiber bundle 19 has a predetermined size. An image forming optical system having a function of forming an image may be adopted.
[0039]
A fiber receiver 46 that holds the cap 43 near the rear end of the image guide fiber bundle 19 is fixed to a fixed frame 51 disposed on the outer peripheral side at two locations in the longitudinal direction. For example, as shown in FIG. 4 (B), one end side of the fiber receiver 46 is fixed by positioning adjustment with three screws 52 from three circumferential directions. Further, as shown in FIG. 5, even at a position near the other end, it is similarly fixed with screws 52 ′ from three places in the circumferential direction.
[0040]
Further, as shown in FIG. 4A, the fixed frame 51 is fixed to the outer frame 53 on the outer peripheral side with screws 54. Note that the fixed frame 51 of the imaging unit 41 is fixed to the L-shaped attachment member 45 by screws 44b.
[0041]
Further, the relay optical system 47 facing the emission end face 19 a (see FIG. 5) of the image guide fiber bundle 19 held by the fiber receiver 46 is attached to the lens frame 56. The front end side of the lens frame 56 is fitted to the outer frame 53, and the CCD frame 48a of the CCD 48 is adjusted and fixed to the rear end side of the lens frame 56. That is, it is fixed in a state adjusted so that the imaging surface of the CCD 48 is positioned at a position where the image is formed with a predetermined size by the relay optical system 47.
[0042]
Further, the fitting portion between the lens frame 56 and the outer frame 53 is also fixed by adjusting the focus in the direction of the optical axis O of the relay optical system 47 with a screw 57. The optical image transmitted to the output end face 19a of the image guide fiber bundle 19 is adjusted so that it is clearly imaged with a predetermined size on the imaging surface of the CCD 48 via the relay optical system 47, and then the frame 35 is cut. It is attached via the attachment member 45 in the vicinity of the notch 35a.
[0043]
In this case, the position of the output end face 19a of the image guide fiber bundle 19 on the optical axis O of the relay optical system 47 is also adjusted by adjusting the position at which the fiber receiver 46 is fixed from the three circumferential directions by screws 52 and the like. It is attached to the frame 35 via the attachment member 45 in a state adjusted so that the central axis O ′ coincides with the optical axis O.
[0044]
As shown in FIG. 4C of the CC cross section of FIG. 3, in addition to the image guide fiber bundle 19, the suction pipe 36 and a bending operation wire for performing a bending operation are provided inside the grip portion 11. A built-in object such as a coil serving as a guide member through which 25 is inserted is inserted, and the coil is held by a coil receiver 59 fixed to the frame 35 at the position of FIG. As shown in FIGS. 4 (A) to 4 (C), the lower end of the frame 35 is bent in an L shape, and maintains a predetermined strength in a direction perpendicular to the plate surface. I can do it.
[0045]
As described above, in the present embodiment, the image guide fiber bundle 19 inserted through the insertion portion 2 is linearly connected to the fiber receiver 46 of the imaging unit 41 fixed to a portion shifted from the center position inside the grip portion 11. The outgoing end portion is fixed so that a bent portion 42 (and a space portion that allows the bent portion 42 to be deformed) is formed smoothly and smoothly from a straight state instead of the extended state. It is a feature that it is made to be.
[0046]
That is, as shown in FIG. 3, the image guide fiber bundle 19 extending rearwardly along the substantially center line C from the proximal end portion of the insertion portion 2 passes through a portion bent by the bending portion 42 inside the grip portion 11. The rear end portion is on the central axis O ′ so as to be fixed to the imaging unit 41.
[0047]
In addition, as described above, the imaging unit 41 is attached to the inside of the gripper 11 after adjustment, and fine adjustment is further performed after attachment.
Therefore, in this embodiment, as shown in FIGS. 3 and 4B, the three-direction screws 52 can be easily adjusted by a driver (not shown) through an opening provided in the outer frame 53.
In this case, as shown in FIG. 3 and the like, the imaging unit 41 is arranged at a position shifted from the vicinity of the center of the gripping part 11 by the notch 35a. The work of performing fine adjustment can be easily performed without obstructing other built-in objects. It should be noted that the screws 57 for fixing the lens frame 56 and the outer frame 53 can be easily readjusted and fixed in the same manner.
[0048]
Therefore, according to the present embodiment, the front end and the rear end of the image guide fiber bundle 19 are fixed, but in the middle, specifically, since the bending portion 42 is formed inside the grip portion 11, Even when the tension is applied to both ends of the image guide fiber bundle 19 when the portion 2 is bent or curved, the tension is reduced by the deformation of the image guide fiber bundle 19 in the bending portion 42. The image guide fiber bundle 19 is absorbed so that almost no force acts on the image guide fiber bundle 19 so that a predetermined imaging function in the imaging unit 41 can be maintained.
[0049]
For example, even if the bending operation is repeated, if tension is applied to both ends of the image guide fiber bundle 19 in accordance with the bending operation, the influence is caused by the deformation of the image guide fiber bundle 19 in the bending portion 42. This can be eliminated or greatly reduced, and a predetermined imaging function can be maintained over a long period of time with a simple configuration.
[0050]
Further, in the individual image guide fiber bundles 19 at the time of manufacturing, even if there is some variation in the length, the amount of bending in the bending portion 42 changes, so that the fixing position in the gripping portion 11 does not change. It can also be fixed. That is, the allowable variation amount can be increased with respect to the length of the image guide fiber bundle 19 and the manufacturing cost can be reduced.
[0051]
Furthermore, by shifting the shaft, the image guide fiber bundle 19 is fixed while easily avoiding other built-in components such as a coil serving as a guide member through which the suction conduit 36 and the wire 25 are inserted. 41 can be attached to the frame 35, and the risk of breaking the image guide fiber bundle during assembly is reduced.
[0052]
(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIG.
As described in the first embodiment described above, even when the insertion portion 2 is bent or the length of the image guide fiber bundle 19 varies due to the formation of the bending portion 42, those bending portions 42 are not. Although the influence can be eliminated or reduced, a structure in which the amount of bending of the image guide fiber bundle 19 can be adjusted and the image pickup unit 41 is fixed to the frame 35 as described below may be used.
[0053]
FIG. 6 shows a view of the attachment member 45 from the lower side in FIG. 5 (however, the left and right direction is reversed so that the left and right directions are the same as FIG. 5). In FIG. A long hole 61 that is elongated in the longitudinal direction of the portion 11 (left-right direction in FIG. 6) is provided, and the position where the imaging unit 41 is fixed to the frame 35 via the L-shaped attachment member 45 with the screw 44a (the gripping portion). 11 in the longitudinal direction).
[0054]
For example, when it is desired to reduce the amount of deflection, the attachment member 45 may be fixed closer to the rear end of the gripping portion 11, that is, toward the left side in FIG. 6, and conversely, when it is desired to increase the amount of deflection, the attachment member What is necessary is just to fix 45 to the front end of the holding part 11, ie, the right side in FIG. A screw hole into which the screw 44a is screwed is formed on the frame 35 side.
[0055]
For example, even when there is variation in the length of the image guide fiber bundle 19, the imaging unit 41 can be fixed by setting the same deflection amount between products depending on the fixing position of the mounting member 45.
Thus, in this embodiment, in addition to the effects of the first embodiment, variations such as the length of the image guide fiber bundle 19 can be absorbed, and a more appropriate amount of deflection can be adjusted. Therefore, it is possible to provide an endoscope in which the image guide fiber bundle is less expensive to manufacture and the image guide fiber bundle is more difficult to break.
[0056]
【The invention's effect】
As described above, according to the present invention, an elongated insertion portion,
A grip portion provided on a proximal end side of the insertion portion, and capable of being gripped by an operator;
An objective optical system provided at the distal end of the insertion portion and capable of transmitting an optical image of a subject into the insertion portion;
The optical image incident from the distal end side through the objective optical system can be transmitted to the proximal end side, and is inserted into the insertion portion so that the proximal end side extends from the insertion portion to the inside of the gripping portion. An image guide fiber bundle,
An optical system emitting portion that is provided on the proximal end side of the image guide fiber bundle and emits the optical image transmitted from the distal end side;
An imaging unit that is optically connected to the optical image emitting unit and capable of imaging an optical image transmitted from the optical image emitting unit;
In an endoscope having
An optical axis of an optical image emitted from the optical image emitting unit toward the imaging unit is shifted with respect to a central axis of a portion where the image guide fiber bundle extends inside the gripping unit. Since the imaging unit is arranged, the image guide when the insertion part is bent is formed more smoothly in the part reaching the output end of the image guide fiber bundle than when the axes are coaxial. Eliminating or reducing the tension acting on the fiber bundle, making the image guide bundle more difficult to break, and absorbing the influence of variations in the individual image guide fiber bundles due to the flexure, so the manufacturing cost of the image guide fiber bundle is not incurred. In addition, a predetermined imaging function can be maintained with easy assembly.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an appearance of an endoscope according to a first embodiment of the present invention.
FIG. 2 is a cross-sectional view showing the internal configuration on the distal end side of the insertion portion.
FIG. 3 is a cross-sectional view showing an internal configuration around a grip portion of an operation unit.
4 is an enlarged cross-sectional view of each of the AA cross section, the BB cross section, and the CC cross section in FIG. 3;
FIG. 5 is an enlarged cross-sectional view showing an imaging unit portion of FIG. 3;
FIG. 6 is a side view showing an attachment member to which an imaging unit according to the second embodiment of the present invention is attached.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Endoscope 2 ... Insertion part 3 ... Operation part 4 ... Universal cord 5 ... Connector 8 ... Tip part 9 ... Bending part 10 ... Flexible part 11 ... Grip part 12 ... Bending lever 18 ... Objective lens system 19 ... Image guide Fiber bundle 20 ... Channel 31 ... Exterior member 35 ... Frame 35a ... Notch 41 ... Imaging unit 42 ... Deflection part 43 ... Base 45 ... Mounting member 46 ... Fiber receiver 47 ... Relay optical system 48 ... CCD
48a ... CCD frame 50 ... signal cable 51 ... fixed frame 53 ... outer frame 56 ... lens frame

Claims (2)

An elongated insert,
A grip portion provided on a proximal end side of the insertion portion, and capable of being gripped by an operator;
An objective optical system provided at the distal end of the insertion portion and capable of transmitting an optical image of a subject into the insertion portion;
The optical image incident from the distal end side through the objective optical system can be transmitted to the proximal end side, and is inserted into the insertion portion so that the proximal end side extends from the insertion portion to the inside of the gripping portion. An image guide fiber bundle,
An optical system emitting portion that is provided on the proximal end side of the image guide fiber bundle and emits the optical image transmitted from the distal end side;
An imaging unit that is optically connected to the optical image emitting unit and capable of imaging an optical image transmitted from the optical image emitting unit;
In an endoscope having
The optical axis of the optical image emitted from the optical image emitting unit toward the imaging unit is shifted with respect to the central axis of the portion where the image guide fiber bundle extends into the gripping unit. Endoscope characterized by. The endoscope according to claim 1, further comprising an adjustment fixing unit configured to adjust the amount of bending of the image guide fiber bundle so as to fix the imaging unit.

Images