JP2016214300A - Endoscope - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an endoscope whose diameter of an insertion part can be made thin, and which can prevent entry of steam into an optical system.SOLUTION: An endoscope 1 includes: one observation window 21 provided to the tip of an insertion part 2 for acquiring two optical images having parallaxes; a holding frame 48 for holding the observation window 21 by an adhesive put into a first clearance C1 formed between itself and the observation window 21; a first adhesion layer 51 formed in the first clearance C1, a frame member provided in surface contact with the tip surface of the holding frame 48 so as to cover the outer peripheral part of the tip side of the observation window 21, which is fixed by an adhesive put into a second clearance C2 formed between itself and the observation window 21 and smaller than the first clearance C1; and second adhesion layer 52 formed in the second clearance C2, which is thinner than the first adhesion layer 51.SELECTED DRAWING: Figure 6

Description

  The present invention relates to an endoscope in which an observation window is provided at a distal end portion of an insertion portion.

  As is well known, endoscopes are widely used for observation and treatment of living bodies (inside body cavities), inspections and repairs in industrial plant facilities, and the like. In such an endoscope, an imaging device provided with an objective optical system is fixed to the distal end portion of the insertion portion.

  Such an imaging apparatus has an optical system provided so as to be exposed at the tip. For example, Patent Document 1 discloses an imaging apparatus for an endoscope that is fixed with an adhesive to a lens frame that holds an optical system on the observation target surface side.

  By the way, in recent years, as disclosed in, for example, Patent Document 2, an endoscope having a two-dimensional imaging apparatus that has two optical systems and can obtain a three-dimensional image from the parallax of a subject image by these optical systems. Are known.

JP 2003-230533 A JP 2014-160240 A

  However, as disclosed in Patent Document 2, an endoscope having two right and left optical systems has a larger gap between the lens frame holding these two optical systems than a conventional monocular endoscope. As a result, water vapor easily enters the adhesive filled in the large gap, and there is a problem that condensation tends to occur on the inner surface side of the optical system.

  Therefore, if the structure of the imaging side device of the endoscope as disclosed in Patent Document 1 is set so that water vapor does not enter, the distance between the two optical systems becomes large, and the tip where the stereoscopic imaging device is built-in There exists a problem that a part enlarges and the diameter reduction of an insertion part is inhibited.

  Therefore, the present invention has been made in view of the above problems, and an endoscope that can reduce the diameter of the insertion portion without increasing the size of the distal end portion, and prevents the entry of water vapor into the optical system. The purpose is to provide.

  An endoscope according to an aspect of the present invention is provided between the observation window and one observation window that is provided at the distal end of an insertion portion that is inserted into a subject and obtains two optical images having parallax. A holding frame that holds the observation window by being filled with an adhesive in a first clearance, a first adhesive layer that is formed in the first clearance, and a tip surface of the holding frame are in surface contact. It is provided so as to cover the outer peripheral portion on the distal end side of the observation window, and is formed between the observation window and is fixed by being filled with an adhesive in a second clearance smaller than the first clearance. A frame member and a second adhesive layer formed in the second clearance and thinner than the first adhesive layer.

  According to the present invention, it is possible to provide an endoscope that can reduce the diameter of the insertion portion and prevent water vapor from entering the optical system.

The side view which shows the whole structure of the endoscope of 1 aspect of this invention The perspective view which shows the structure of an insertion part similarly Same as above, front view showing the configuration of the tip Sectional drawing which shows a part of front-end | tip part and curved part along the IV-IV line of FIG. The exploded sectional view explaining the state which fixes a tip lens to an objective lens unit similarly Sectional drawing which shows the state in which the front lens was fixed to the objective lens unit The exploded sectional view explaining the state which fixes a tip lens to the objective lens unit of a modification same as the above Sectional drawing which shows the state by which the front-end | tip lens was fixed to the objective lens unit of a modification similarly

  Hereinafter, the endoscope according to the present invention will be described. In the following description, the drawings based on each embodiment are schematic, and the relationship between the thickness and width of each part, the thickness ratio of each part, and the like are different from the actual ones. It should be noted that the drawings may include portions having different dimensional relationships and ratios between the drawings.

  Note that the endoscope in the following description of the configuration will be described by taking a so-called flexible endoscope having an insertion portion flexible for insertion into the digestive organs of the upper or lower part of the living body, but is not limited thereto. In addition, the technique can be applied to a so-called rigid endoscope having a hard insertion portion used for surgery.

  First, an endoscope according to one embodiment of the present invention will be described with reference to the drawings. 1 is a side view showing the overall configuration of the endoscope of the present invention, FIG. 2 is a perspective view showing the configuration of the insertion portion, FIG. 3 is a front view showing the configuration of the distal end portion, and FIG. FIG. 5 is an exploded cross-sectional view illustrating a state in which the front end lens is fixed to the objective lens unit, and FIG. 6 is a front end lens fixed to the objective lens unit. FIG. 7 is an exploded sectional view illustrating a state in which the tip lens is fixed to the objective lens unit according to the modification. FIG. 8 is a cross section illustrating a state in which the tip lens is fixed to the objective lens unit according to the modification. FIG.

  As shown in FIG. 1, an endoscope 1 includes an insertion portion 2 that is inserted into a subject, an operation portion 3 that is connected to the proximal end side of the insertion portion 2, and extends from the operation portion 3. The universal cord 8 and the connector 9 provided at the extended end of the universal cord 8 are provided.

  The endoscope 1 is electrically connected to a control device such as a video processor and an external device (not shown) that is a lighting device via a connector 9.

  The operation section 3 is provided with an up / down bending operation knob 4 for bending the bending section 12 of the insertion section 2 in the up / down direction and a left / right bending operation knob 5 for bending the bending section 12 in the left / right direction.

  Further, the operation unit 3 is provided with a fixed lever 6 that fixes the turning position of the up / down bending operation knob 4 and a fixing knob 7 that fixes the turning position of the left / right bending operation knob 5.

  The insertion portion 2 has a distal end portion 11, a bending portion 12, and a flexible tube portion 13 connected in order from the distal end side, and is formed in an elongated shape so that it can be easily inserted into a subject.

  The bending portion 12 is provided in the distal end portion 11 by being bent in, for example, four directions of up, down, left, and right by the turning operation of the up / down bending operation knob 4 and the left / right bending operation knob 5, which is not shown here. The observation direction of the imaging device can be changed, or the insertability of the distal end portion 11 in the subject can be improved.

Next, the components disposed on the distal end surface of the distal end portion 11 will be briefly described with reference to FIGS. 2 and 3.
As shown in FIGS. 2 and 3, a tip cover 25 is provided on the tip surface of the tip portion 11. Note that the tip cover 25 provided at the tip portion 11 has a disk shape as an example, and is made of, for example, resin.

  The tip cover 25 is formed with a plurality of holes, and the tip lens 21 as an observation window disposed at the forefront of the imaging device described later in these holes, here, a rectangular shape that is two illumination windows The illumination lens 22 and a cleaning nozzle 23 for supplying air or water mainly toward the tip lens 21 are disposed.

  Note that the tip lens 21 here has, for example, a substantially oval shape, and is optical so that two optical images are incident with parallax so that the same subject image becomes a stereoscopic image. It is a plano-concave lens as an objective optical system in which two concave portions 21a and 21b having characteristics are formed on one surface.

  One hole provided in the distal end cover 25 constitutes a channel opening 24 of a treatment instrument channel described later. Furthermore, there is a tip cover 25 having an observation object cleaning port for forward air supply / water supply which is not provided here.

Here, the internal structure of the front-end | tip part 11 and the bending part 12 is demonstrated using FIG.
As shown in FIG. 4, in the distal end portion 11 of the insertion portion 2, a distal end constituting portion 26 constituting a distal end portion main body made of a hard metal is provided here.

  An annular cutting edge bending piece 36 is connected to the distal end component portion 26 so as to be fitted on the outer peripheral portion on the proximal end side. Note that the distal end component 26 is provided with the aforementioned distal end cover 25 that constitutes the distal end surface of the distal end portion 11. The tip cover 25 is disposed so as to cover the tip surface and the tip outer peripheral portion of the tip component portion 26.

  A plurality of annular bending pieces 37 provided inside the bending portion 12 are rotatably connected to the rear of the most advanced bending piece 36 connected to the tip constituting portion 26. The outer periphery of the plurality of bending pieces 36 and 37 is covered with a bending rubber 38 as an outer skin.

  The curved rubber 38 covers the outer periphery of the distal end component portion 26 from the proximal end of the distal end cover 25. And the front-end | tip part of the curved rubber 38 is being fixed to the outer peripheral part of the front-end | tip structure part 26 by the pincushion adhesion part 38a.

  The plurality of bending pieces 37 disposed inside the bending portion 12 are a plurality of, for example, four bending operation wires 39a (FIG. 4) whose tips are respectively fixed to wire clamps 39 provided on the cutting edge bending piece 36. Then, the bending portion 12 is bent by a turning operation by pulling and loosening.

  The four bending operation wires 39a are pulled and loosened by rotating the bending operation knobs 4 and 5 provided in the operation unit 3 shown in FIG. In addition, since the detailed structure which carries out bending operation of the bending part 12 is known, those description is abbreviate | omitted.

A plurality of insertion holes are formed in the tip component portion 26 provided in the tip portion 11.
In the plurality of insertion holes of the distal end constituting portion 35, a cleaning nozzle 23 (not shown), a treatment instrument channel connection pipe 44 that is a metallic pipe, an imaging device 45, two illumination lens units (not shown), and two light guide bundles are held. A tube is inserted.

  The treatment instrument channel connection tube 44 is inserted from the proximal end side of the insertion hole of the distal end configuration portion 35. A treatment instrument channel 43, which is a flexible tube body, is connected to the proximal end portion of the treatment instrument channel connection pipe 44.

  The treatment instrument channel 43 is inserted into the insertion section 2 and the operation section 3 and is disposed up to the treatment instrument insertion port of the operation section 3.

  The imaging device 45 has an objective lens unit 46 on the distal end side. The objective lens unit 46 has a lens holding frame 48 that holds two objective lens groups 47 a and 47 b composed of a plurality of objective lenses including the tip lens 21.

  The imaging device 45 is inserted from the proximal end side into the insertion hole of the distal end component 26 so that the distal end portion of the lens holding frame 48 of the objective lens unit 46 protrudes from the distal end surface of the distal end component 26.

  The image pickup device 45 is provided with one image sensor 40 as an image pickup unit including a solid-state image pickup device such as a CCD or CMOS, and the one image sensor 40 includes two objective lenses of the objective lens unit 46. Lights of two images (subject images) due to reflected light from the subjects condensed by the groups 47a and 47b are detected, and an imaging signal is output by photoelectric conversion.

  This imaging signal is output to a video processor (not shown), which is an external device, via an electrical connector connected to the insertion unit 2, the operation unit 3, the universal cord 8, and the connector 9 shown in FIG. Then, the video processor performs image processing based on the imaging signal and outputs the processed image to a monitor (not shown), whereby a stereoscopic endoscope image is displayed on the monitor.

  Here, using FIG. 5 and FIG. 6, mounting of the front lens 21 held by the lens holding frame 48 of the objective lens unit 46 provided in the imaging device 45 at the front end will be described.

  As shown in FIG. 5, the front lens 21 is mounted such that a part thereof is embedded in a recess 48 a formed at the front end of the lens holding frame 48.

  At this time, the photographing optical axes of the two objective lens groups 47a and 47b and the two concave portions 21a and 21b are respectively aligned between the front lens 21 and the inner wall forming the concave portion 48a of the lens holding frame 48. In order to perform optical adjustment so that two images of the subject can be formed by the above, a predetermined clearance C1 is formed so as to be movable in a direction orthogonal to the imaging optical axis.

  Then, as shown in FIG. 6, the tip lens 21 is optically adjusted, and then the lens holding frame 48 and the outer peripheral portion (outer periphery) where the protective frame 49 that is an annular frame member protrudes from the lens holding frame 48. The lens holding frame 48 and the protective frame 49 are fixed by filling the clearance C1 with a filler such as an adhesive.

  The protective frame 49 is, for example, a substantially oval annular member having a hole similar to the shape of the outer peripheral portion of the tip lens 21. The protective frame 49 is provided on the distal end side of the imaging device 45 that is on the outer side of the lens holding frame 48, and the end surface 49 a facing the lens holding frame 48 is in contact with the distal end surface 48 b of the lens holding frame 48. It is fixed.

  In this state, in the objective lens unit 46, the adhesive layer 51 is formed in a predetermined clearance C1 formed between the outer peripheral surface of the tip lens 21 and the inner peripheral surface forming the concave portion 48a of the lens holding frame 48. A minute adhesion thinner than the adhesive layer 51 in a predetermined clearance C2 (C1> C2) formed between the outer peripheral surface of the front lens 21 smaller than the predetermined clearance C1 and the inner peripheral surface of the protective frame 49. Layer 52 is formed.

  The predetermined clearance C1 and the predetermined clearance C2 are in communication as in the present embodiment, and the adhesive layer 51 and the adhesive layer 52 may be integrally formed.

  Further, the protective frame 49 is also coated with an adhesive 53 around the outer peripheral portion so as to be firmly fixed to the lens holding frame 48.

  In this manner, the front lens 21 has a minute clearance C2 filled in the predetermined clearance C2 between the protective layer 49 and the adhesive layer 51 filled in the predetermined clearance C1 with respect to the lens holding frame 48 for optical adjustment. The adhesive layer 52 is fixed to the lens holding frame 48.

  The protective frame 49 is also fixed to the lens holding frame 48 in a state in which the end surface 49 a is in contact with the front end surface 48 b of the lens holding frame 48 and is in surface contact therewith.

  As described above, the tip lens 21 serving as an objective optical system for obtaining two optical images so as to have parallax by one is provided with a predetermined clearance C1 in the lens holding frame 48, so that optical adjustment can be easily performed. Yes.

  Since the distal lens 21 serving as an observation window exposed at the distal end surface of the distal end portion 11 is fixed by a minute adhesive layer 52 with the protective frame 49, it is difficult for water vapor from the outside to enter. This prevents the humidity of the lens from becoming higher than the outside and prevents the condensation on the inner surface side of the front lens 21.

  That is, in the structure for fixing the front lens 21 to the lens holding frame 48, the adhesive layer 51 that fills the predetermined clearance C1 for optical adjustment is provided on the inner side, and the protective frame 49 is provided on the outer side of the adhesive layer 51. Since the adhesive layer 52 is provided so as to be in surface contact with the surface and fills the minute predetermined clearance C2, it is difficult for water vapor from the outside to enter, and it is difficult for condensation to occur on the inner surface side of the tip lens 21. It becomes.

  The endoscope 1 is used as a so-called stereoscopic endoscope that obtains two optical images so that one tip lens 21 provided at the forefront of the imaging device 45 and exposed at the tip 11 has parallax. In addition, since there is only one image sensor 40 that detects two optical images, the imaging device 45 can be reduced in size, and the insertion portion 2 can be reduced without increasing the size of the distal end portion 11 in which the imaging device 45 is built. There is no hindrance to the diameter reduction.

  Therefore, the endoscope 1 according to the present embodiment can reduce the diameter of the insertion portion 2 without increasing the size of the distal end portion 11 and prevent water vapor from entering the optical system of the imaging device 45. Can do.

(First modification)
As shown in FIGS. 7 and 8, the cross-sectional shapes of the lens holding frame 48 and the protective frame 49 may be changed to prevent water vapor from entering the optical system of the imaging device 45.

  Specifically, convex portions 48c protruding from the front end surface 48b of the lens holding frame 48 are formed in the circumferential direction, and the protective frame 49 is formed in an L-shaped cross section.

  Here, as shown in FIG. 7, the front lens 21 is mounted so as to be partially embedded in the concave portion 48 a formed at the front end of the lens holding frame 48, and the concave portion 48 a of the front lens 21 and the lens holding frame 48 is provided. A predetermined clearance C1 is formed between the inner wall to be formed so as to be movable in a direction perpendicular to the photographing optical axis in order to perform optical adjustment.

  As shown in FIG. 8, the front lens 21 is mounted so as to cover the outer periphery of the lens holding frame 48 and the annular protective frame 49 protruding from the lens holding frame 48 after optical adjustment. 48 and the protective frame 49 are fixed by an adhesive.

  Again, the protective frame 49 is fixed so that the end surface 49 a facing the lens holding frame 48 comes into contact with the front end surface 48 b of the lens holding frame 48.

  In this state, a predetermined clearance C3 (C1 ≦ C3) equal to or greater than the predetermined clearance C1 is formed between the outer peripheral surface of the convex portion 48c of the lens holding frame 48 and the outer peripheral surface of the protective frame 49, and the front lens 21, the lens An adhesive layer 51 is formed in a U-shaped space formed by the holding frame 48 and the protective frame 49.

  In this case as well, a thin adhesive layer is provided between the outer peripheral surface of the front lens 21 and the inner peripheral surface of the protective frame 49 within a predetermined clearance C2 (C2 <C1 ≦ C3) smaller than the predetermined clearances C1 and C3. 52 is formed, and an adhesive 53 is applied around the outer periphery of the protective frame 49.

  In the endoscope 1 of this modified example configured as described above, the structure for fixing the distal lens 21 to the lens holding frame 48 has an adhesive layer 51 that fills predetermined clearances C1 and C3 in a U-shaped cross section. Similarly to the above, the thin adhesive layer 52 that fills the minute predetermined clearance C <b> 2 outside the adhesive layer 51 is provided, so that water vapor from the outside can be more difficult to enter.

  Therefore, the endoscope 1 can be configured to prevent condensation from forming on the inner surface side of the tip lens 21 of the imaging device 45, and has the above-described effect.

  The invention described in the above-described embodiment is not limited to the embodiment and modifications, and various modifications can be made without departing from the scope of the invention in the implementation stage. Further, the above embodiments include inventions at various stages, and various inventions can be extracted by appropriately combining a plurality of disclosed constituent elements.

  As an example, as in the above-described embodiment, the light of two images (subject images) by the reflected light from the subject collected by the two objective lens groups 47a and 47b of the objective lens unit 46 is detected by one image sensor 40. Instead of a simple configuration, a configuration in which detection is performed by two image sensors may be used.

  Further, as long as the optical axes of the two objective lens groups 47a and 47b and the two concave portions 21a and 21b can be optically adjusted within the clearance C1, the shape is not limited to a substantially oval shape as in the above embodiment. Alternatively, other shapes such as an elliptical shape or a rounded polygon may be used. At this time, the protective frame 49 only needs to have a shape that covers the outer periphery of the tip lens 21 and does not obstruct the optical path of the objective optical system.

  Even if some constituent elements are deleted from all the constituent elements shown in the embodiment described above, if the stated problem can be solved and the stated effect can be obtained, The deleted configuration can be extracted as an invention.

DESCRIPTION OF SYMBOLS 1 ... Endoscope 2 ... Insertion part 3 ... Operation part 4 ... Up / down bending operation knob 5 ... Left / right bending operation knob 6 ... Fixed lever 7 ... Fixed knob 8 ... Universal cord 9 ... Connector 11 ... Tip part 12 ... Bending part 13 ... Flexible tube 21 ... End lens 21a, 21b ... Recess 22 ... Illumination lens 23 ... Cleaning nozzle 24 ... Channel opening 25 ... End cover 26 ... End constituent part 35 ... End constituent part 36, 37 ... Bending piece 38 ... Curved rubber 38a ... Pincushion bonding portion 39 ... Wire clamp 39a ... Bending operation wire 40 ... Image sensor 43 ... Treatment instrument channel 44 ... Treatment instrument channel connection tube 45 ... Imaging device 46 ... Objective lens units 47a, 47b ... Objective lens group 48 ... Lens holding frame 48a ... concave portion 48b ... tip surface 48c ... convex portion 49 ... protective frame 49a ... end surface 51, 52 ... adhesive layer 53 ... adhesive C1, C2, C3 ... clear Nsu

Claims (4)

One observation window provided at the distal end of the insertion portion to be inserted into the subject and obtaining two optical images having parallax;
A holding frame that holds the observation window by being filled with an adhesive in a first clearance formed between the observation window and the observation window;
A first adhesive layer formed within the first clearance;
A second clearance that is provided to be in surface contact with the distal end surface of the holding frame and covers an outer peripheral portion on the distal end side of the observation window, and is formed between the observation window and smaller than the first clearance. A frame member that is filled and fixed with an adhesive, and
A second adhesive layer formed within the second clearance and thinner than the first adhesive layer;
An endoscope comprising:   The endoscope according to claim 1, wherein the first clearance and the second clearance communicate with each other.   The endoscope according to claim 1, wherein the observation window is an objective optical system that forms an image with parallax with respect to the same subject image.   The endoscope according to claim 1, further comprising one imaging unit that detects the two optical images having the parallax.

Images