JP2005334189A - Observation unit for endoscope and endoscope - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an observation unit facilitating adhesion and fixing between a unit distal end and a unit body by effectively preventing a phenomenon of the outflow of fluid from a clearance filled with adhesive to an interior and preventing a phenomenon of the outflow of the adhesive to the unit interior and to provide an endoscope equipped with the observation unit. <P>SOLUTION: This observation unit for the endoscope is fixed to an insertion tube distal end of the endoscope to be inserted in the body cavity, and is provided with, at least, a first outer frame and a second outer frame forming the external shape of the observation unit. The respective frames are fitted to each other and, and in their fitted state, filled with the adhesive in the space formed between the respective frames to be fixed together. The space is disposed with a seal member having the thickness and elasticity larger than the space and preventing the fluid from entering into the interior of the unit through the space. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an observation unit for observing and imaging a test object disposed at a distal end portion of an insertion tube and an endoscope including the observation unit.

  In an endoscope, an observation unit includes an objective optical system and an image sensor for observing the inside of a body cavity. The observation unit has a shape that fits into a cavity provided inside the distal end portion of the insertion tube that is inserted into the body cavity. The observation unit is fixed while being fitted into the cavity with the end of the unit exposed to the outside of the endoscope body. Such an observation unit is disclosed in Patent Document 1 below, for example.

JP-A-8-56894

  As described above, since the observation unit is a member disposed at the distal end portion of the insertion tube of the endoscope, it is desired to reduce the diameter and size. In order to meet the demand and protect each member disposed inside, it is preferable that the unit main body is made of a thin metal material. On the other hand, it is necessary to refrain from using a conductive material such as a metal material at the tip of the unit exposed to the outside as much as possible from the viewpoint of safety.

  Therefore, as disclosed in Patent Document 1, the conventional observation unit has a resin unit tip and a portion other than the tip formed of a thin metal, that is, the unit main body, firmly fixed with an adhesive. Fixed and configured. As a result, it is possible to meet demands such as reducing the diameter while ensuring high safety.

  Here, in the process of bonding and fixing the unit tip and the unit main body, the adhesive is not necessarily completely injected into the space (adhesive injection space) formed between the two bonding margins. Unexpected voids may occur after curing. In addition, moisture may enter the inside from the generated gap, and a phenomenon such as cloudiness that hinders observation with high image quality may be induced. In addition, the adhesive may flow into the unit from the adhesive injection space. In particular, in the case of an observation unit disposed in a magnifying endoscope having a zoom function or a confocal endoscope in which the focal position is slightly changed in the optical axis direction, if the adhesive flows into the objective optical system, This may hinder smooth driving of the system.

  Due to the above circumstances, in the observation unit manufacturing process, the operation of bonding and fixing the tip of the unit and the unit main body has to be very precise and complicated.

  Therefore, in view of the above circumstances, the present invention effectively prevents the phenomenon that fluid flows out from the gap generated in the space where the adhesive is injected, and also prevents the phenomenon that the adhesive flows out into the unit. An object of the present invention is to provide an observation unit that can easily perform bonding and fixing between a unit tip and a unit body, and an endoscope on which the observation unit is mounted.

  In order to solve the above-described problems, an endoscope observation unit according to the present invention is an observation unit that is fixed to the distal end of an insertion tube inserted into a body cavity of an endoscope, and has an outer shape of the observation unit. A space formed between each frame in a state in which the first outer frame is fitted to the second outer frame. A seal member that is fixed by injecting an adhesive into the space and has a larger thickness and elasticity than the space, and prevents fluid from entering the unit through the space is disposed in the space. It is characterized by being.

  As described above, by arranging a seal member in the area where each frame is fixed and bonded, the phenomenon of fluid flowing out into the unit through the gap generated when the injected adhesive hardens is effective. Can be prevented. At the same time, according to the present invention, since the space for injecting the adhesive is sealed by the seal member, a phenomenon of flowing into the unit from the space during the injection of the adhesive is effectively prevented. Therefore, in the manufacturing process, the burden on the operation of injecting the adhesive can be reduced, the working efficiency can be improved, and the yield can be kept low.

  In the present invention, the first outer frame is a distal end frame whose one end is exposed to the outside of the endoscope, and the second outer frame is a main body frame for covering a member disposed inside the observation unit. In some cases, that is, in a configuration in which a tip frame employed to secure safety while reducing the diameter is fitted and bonded to the main body frame, it is more preferably implemented (Claim 2). In addition, this invention can be implemented even if it is the structure which a main body frame fits to a front-end | tip frame.

  In the observation unit, it is desirable to form the tip frame using a resin in order to ensure safety. Moreover, it is desirable to form the main body frame using a thin metal from the viewpoint of reducing the diameter and protecting each member provided inside the imaging element or the like.

  Further, in order to enhance the effectiveness of the sealing effect by the sealing member, it is desirable to dispose the sealing member along the circumferential direction of each frame.

  According to the invention described in claim 4, the first outer frame and the second outer frame have shapes similar to each other at least in a portion where the first outer frame is fitted to the second outer frame. It is desirable to be present (claim 4). By adopting a similar shape, the space created between the regions when fitted is almost uniform everywhere, and the seal member is not a special shape, and a shape corresponding to the similar shape can be adopted. The similar shape is preferably a cylindrical shape from the viewpoint of minimizing the area occupied by the observation unit at the distal end portion of the endoscope.

  In addition, in this text, the sealing member is a general term for members used for preventing fluid leakage and entry of foreign matter. For example, an O-ring is suitable as the seal member (claim 6).

  Further, the endoscope observation unit may be configured to have a magnifying optical system for performing magnifying observation therein or may be configured to include a confocal optical system for performing confocal observation.

  As described above, according to the endoscope of the present invention, moisture or the like flowing from the outside of the endoscope is formed with the adhesive curing by disposing a seal member such as an O-ring between the bonding regions of the two frames. It is possible to effectively prevent the phenomenon of entering the unit through the gap. Furthermore, by providing the seal member, the phenomenon that the adhesive enters the unit is also prevented. Accordingly, it is possible to easily execute bonding and fixing of the unit tip and the unit body.

  FIG. 1 is a diagram illustrating an electronic endoscope 100 including two observation units (a confocal observation unit 10 and a normal observation unit 50) for observing a living tissue in a body cavity according to the present embodiment. As shown in FIG. 1, the electronic endoscope 100 of this embodiment includes an insertion portion flexible tube 101, a forceps insertion port 102, an operation portion 103, and a distal end portion main body 101 t of the insertion portion flexible tube 101. Have.

  An insertion portion flexible tube 101 formed in the electronic endoscope 100 is a long tube that is inserted into a body cavity and has flexibility. FIG. 2 is a cross-sectional view of the insertion portion flexible tube 101. The insertion portion flexible tube 101 distal end main body 101t has two cylindrical openings (cavities) with different diameters. In each cavity, a cylindrical confocal observation unit 10 and a normal observation unit 50 having diameters corresponding to the respective diameters are arranged.

  The normal observation unit 50 includes a normal observation objective optical system 51 and an image sensor 52. Then, the normal observation unit 50 captures an observation image using the reflected light from the part in the body cavity of the illumination light irradiated through a light guide (not shown).

  The confocal observation unit 50 is another optical unit for observing the living tissue in the body cavity, and is an optical unit for observing the surface portion and the tomographic portion of the living tissue at a higher magnification than the normal observation unit 50. . The confocal observation unit 50 includes a main body frame 11, a tip frame 12, an O-ring 13, an inner tube 14, a light emitting unit 15 having a single mode optical fiber 15A and a piezoelectric element 15B, an objective optical system 16, a cover glass 17, and a lens barrel. 18 The objective optical system 16 is actually composed of a large number of lenses, but only two lenses are shown in FIG. 2 for convenience.

  The confocal observation unit 10 is a small optical unit that can observe the inside of a living tissue that is a dark part. Therefore, the confocal objective optical system 16 has a high NA and a small size. As a result, the focal length of the confocal objective optical system 16 is very short. Unlike the normal observation, the confocal observation unit 10 is fixed by projecting a predetermined amount from the normal observation unit 50 in the tip body 101t in order to perform the observation by bringing the cover glass 17 into contact with the living tissue. .

  The operation of the confocal observation unit 10 will be outlined. First, laser light is emitted from a light source provided in a processor (not shown). The laser light is incident on the end of a single mode optical fiber 15A (not shown) in the insertion portion flexible tube 101. The laser light incident on the end portion is transmitted through the single mode optical fiber 15A and emitted from the end face 15t of the fiber. The light beam emitted from the end face 15t is focused on the living tissue 400 via the confocal objective optical system 16 and the cover glass 17.

  The light beam focused in the biological tissue 400 is reflected or fluorescent in the biological tissue 400 and is focused in the vicinity of the optical fiber end face 15t via the confocal objective optical system 16. The end face 15t is conjugate with the position where the light beam emitted from the confocal objective optical system 16 is focused on the living tissue 400. The core diameter of the single mode optical fiber 15A is extremely small. Therefore, only the light from the position focused on the living tissue 400 among the light from the living tissue 400 is incident on the inside of the single mode optical fiber 15A, and the other light is the clad portion of the single mode optical fiber 15A. It will be shielded from light. That is, the light incident on the single mode optical fiber 15 </ b> A is only light from a position focused on the living tissue 400.

  The reflected light guided to the processor (not shown) by the single mode optical fiber 15A is processed by the processor 220 and converted into a video signal. The converted video signal is displayed on a monitor (not shown) as an observation image by the confocal objective optical system 16 or recorded in a recording device.

  In addition, a plurality of piezoelectric elements 15B are provided in the vicinity of the end portion of the single mode optical fiber 15A. The piezoelectric element 15B is deformed by applying a voltage to press the single mode optical fiber 15A. As a result, the end face 15t is displaced in a direction perpendicular to the optical axis of the confocal objective optical system 16. When the end surface 15t is displaced in the direction perpendicular to the optical axis, the focal position of the light beam irradiated on the living tissue 400 is also moved in the direction orthogonal to the optical axis in accordance with the displacement of the end surface 15t. In other words, when the end face 15t is displaced in a direction orthogonal to the optical axis, the light beam irradiated on the living tissue 400 scans the surface or the inside of the living tissue 400 along with the displacement. As a result, an image for obtaining a two-dimensional observation image is transmitted from the confocal unit 89 to the processor 220. The confocal observation unit 10 is disposed inside the units such as the light emitting unit 15 and the objective optical system 16 so that the focal position on the living tissue 400 can be moved minutely in the optical axis direction of the objective optical system 16. The members are integrated so as to be slidable in the optical axis direction of the objective optical system 16. Here, the main body frame 11 and the distal end frame 12 are respectively fixed to cylindrical cavities provided at the distal end portion 101t. Therefore, sliding of the members inside the unit in the optical axis direction of the objective optical system 16 is achieved by sliding the inner tube 14 and the lens barrel 18 with respect to the frames 11 and 12.

  Next, a specific configuration of the confocal observation unit 10 which is a characteristic part of the present embodiment will be described in detail. As described above, the confocal observation unit 10 is disposed in a state where it protrudes by a predetermined amount on the tip body 101t. Therefore, the protruding end frame 11 is formed of resin from the viewpoint of safety. In addition, from the viewpoint of reducing the diameter as much as possible, realizing the diameter reduction in order to reduce the burden on the subject during endoscopic observation, and protecting each member disposed inside the unit, The body frame 12 is formed of a thin metal. The metal body frame 12 may be covered with an insulating material (not shown) (for example, insulating tape) from the viewpoint of safety.

  The main body frame 11 and the front end frame 12 are firmly fixed using an adhesive in a state in which a part of one of the frames is fitted in the other frame. In the present embodiment, a part of the front end frame 12 is fixed in a state of being fitted to a part of the main body frame 11. FIG. 3 is an enlarged cross-sectional view showing a portion (a portion to be bonded) where the front end frame 12 is fitted to the body frame 11 in the confocal observation unit 10. Note that FIG. 3 exaggerates the gaps formed between the members for the sake of convenience in order to explain the features of the present embodiment more easily. Therefore, in an actual unit, there is no clear gap as shown in FIG. As shown in FIGS. 2 and 3, the confocal observation unit 10 of the present embodiment is a part of the tip frame 12, more specifically, an end portion (cover) exposed to the outside from the tip portion main body 101t in the tip frame 12. A part of the end opposite to the glass 17 is inserted into the main body frame 11. The main body frame 11 has an adhesive allowance 11 </ b> A on the inner wall at the site of adhesion with the tip frame 12. Similarly, the front end frame 12 has a bonding margin 12 </ b> A on the outer wall at the bonding site with the main body frame 11.

  And in order to ensure the space which inject | pours an adhesive agent, the adhesion allowance 11A is designed by the outer diameter slightly smaller than the adhesion allowance 12A. An adhesive is injected into a space (adhesive injection space) formed between the adhesive allowance 11A and the adhesive allowance 12A. In FIG. 3, the injected adhesive is indicated by hatched areas. The bonding allowance 11A is provided over substantially the entire area of the inner wall of the main body frame 11 where the tip frame 12 is bonded, and the bonding allowance 12A is provided over the entire area of the outer wall of the tip frame 12 where the main frame 11 is bonded. ing. That is, the adhesive is injected evenly in the circumferential direction of the bonded portion of each frame 11, 12.

  The O-ring 13 is a seal member disposed between the main body frame 11 and the front end frame 12. Specifically, the O-ring 13 has a thickness larger than the width of the adhesive injection space formed by the two bonding margins 11A and 12A, and does not hinder the fixing of the main body frame 11 and the tip frame 12. Has elasticity. The O-ring 13 has a donut shape extending along the circumferential direction of the frames 11 and 12. Therefore, when the main body frame 11 and the tip frame 12 are fixed, the adhesive injection space is sealed by the O-ring 13. 4 is a cross-sectional view taken along line AA in FIG. As shown in FIG. 4, in the confocal observation unit 10, at the position where the O-ring 13 is disposed, the main body frame 11, the O-ring 13, and the tip frame 12 are fixed without gaps from the outermost peripheral side. I understand. In the actual unit 10, a small space for moving the lens barrel 18 in the optical axis direction of the objective optical system 16 is provided between the distal end frame 12 and the lens barrel 18 shown in FIG. 4.

  As shown in FIG. 2, in the configuration in which the confocal observation unit 10 is fixed in a cylindrical cavity provided in the tip body 101 t, fluid such as water vapor from the body cavity having the living tissue 400 is transferred to the tip frame 12 and the tip. There is a possibility that the gap between the part main bodies 101t may enter the flexible tube 101 along the direction indicated by the filled arrow line in FIG. Here, if air enters when the adhesive is injected and a gap is generated after curing, the fluid flows out through the gap into the confocal observation unit 10. As a result, fogging or the like occurs in the objective optical system 16, which may adversely affect imaging. However, by providing the O-ring 13 as shown in FIGS. 3 and 4, the space for injecting the adhesive is sealed by the O-ring 13. In other words, the entry path of the fluid into the unit is reliably blocked by the O-ring. Therefore, even in the observation unit formed by fitting the main body frame 11 and the front end frame 12 to each other, the above phenomenon such as fogging can be effectively prevented.

  In addition, the space for injecting the adhesive is sealed by the O-ring 13 so that the adhesive itself before curing is a region in the vicinity of the boundary between the space and the inside of the unit (a region surrounded by a one-dot chain line in FIG. 3). ) The phenomenon of flowing into the unit through L is also effectively prevented. Therefore, in the manufacturing process, the burden on the operation of injecting the adhesive can be reduced, the working efficiency can be improved, and the yield can be kept low.

  The above is the embodiment of the present invention. The present invention is not limited to these embodiments and can be modified in various ranges.

  For example, in the above-described embodiment, the confocal observation unit 10 including the two frames of the main body frame 11 and the tip frame 12 has been described. The endoscope observation unit according to the present invention may be formed using two or more frames, that is, one or more fitting (adhesion) portions. In this case, by providing an O-ring at each fitting site (adhesion site), it is possible to effectively prevent the phenomenon of water vapor and adhesive flowing into the unit.

The endoscope observation unit according to the present invention is not limited to confocal observation. For example, the present invention can be suitably applied to a unit for magnifying observation that realizes magnifying observation of a living tissue by moving some lenses (groups) constituting the objective optical system in the optical axis direction. When the present invention is applied to a unit for magnifying observation, the risk of hindering the movement of the partial lens group can be effectively avoided due to the adhesive flowing into the inside.

  In the above embodiment, the configuration in which the distal end frame 12 is inserted into the main body frame 11 has been described. However, the endoscope observation unit according to the present invention is not limited to this configuration. For example, the main body frame 11 may be configured to be fitted to the tip frame 12.

  Moreover, in the said embodiment, although O-ring is used as a sealing member, it is an illustration to the last. That is, if the sealing member is configured so as to prevent the fluid from flowing out from the adhesive injection space formed between the two bonding margins into the unit and does not hinder the firm bonding, the O -It can be used even if it is other than a ring.

  Moreover, it has been described that the endoscope observation unit of the above embodiment has a cylindrical shape which is the most suitable shape for further downsizing and reducing the diameter of the tip body. In carrying out the present invention, the shape of the unit is not limited to a cylindrical shape. However, when an endoscope unit having a shape other than a cylindrical shape is used, the sealing member also has a shape of the unit, more precisely, a fitting part (adhesion part) of two frames that determines the shape of the unit. ) Formed in a shape corresponding to the shape of the adhesive injection space.

  In the above embodiment, the electronic endoscope 100 including two types of observation units for observing the living tissue in the body cavity has been described. However, in the present invention, the above-described endoscope observation unit is provided alone. It may be an electronic endoscope.

It is a figure which shows the electronic endoscope of embodiment of this invention. It is sectional drawing which shows the structure of the front-end | tip part of the electronic endoscope of embodiment of this invention. It is a figure which expands and shows the fitting part of the main body frame of the confocal observation unit of embodiment, and a front-end | tip frame. It is the sectional view on the AA line in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Confocal observation unit 11 Main body frame 12 Tip frame 13 O-ring 100 Electronic endoscope 101 Insertion part flexible tube 101t Tip part main body

Claims (9)

An observation unit fixed to the distal end of an insertion tube inserted into a body cavity of an endoscope,
Having at least a first outer frame and a second outer frame forming the outer shape of the observation unit;
Each frame is fixed by injecting an adhesive into a space formed between the frames in a state where the first outer frame is fitted to the second outer frame,
Endoscopy observation characterized in that a seal member having a thickness and elasticity greater than that of the space and preventing fluid from entering the unit through the space is disposed in the space. unit. The endoscope observation unit according to claim 1,
The first outer frame is a tip frame whose one end is exposed to the outside of the endoscope,
The endoscope observation unit, wherein the second outer frame is a main body frame for covering a member disposed inside the observation unit. The endoscope observation unit according to claim 1 or 2,
The endoscope observation unit, wherein the seal member is disposed along a circumferential direction of each frame. In the endoscope observation unit according to any one of claims 1 to 3,
The endoscope characterized in that the first outer frame and the second outer frame have shapes similar to each other at least in a portion where the first outer frame is fitted to the second outer frame. Observation unit. The endoscope observation unit according to claim 4,
The endoscopic observation unit characterized in that the similar shape is a cylindrical shape. The endoscope observation unit according to any one of claims 1 to 5,
The endoscope observation unit, wherein the seal member is an O-ring.   The endoscope observation unit according to any one of claims 1 to 6, further comprising a magnification optical system for performing magnification observation inside.   The endoscopic observation unit according to any one of claims 1 to 6, further comprising a confocal optical system for performing confocal observation inside.   An endoscope, wherein the endoscope observation unit according to any one of claims 1 to 8 is disposed at a distal end portion of the insertion tube.

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