JP2005052315A - Endoscope apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve a problem that, when an image pickup optical unit including an image pickup element is stored in an outer case of a rigid member and hardened and fixed with adhesive, a cover glass and a centering glass of the image pickup element are exfoliated by contraction due to hardening of the adhesive. <P>SOLUTION: When the image pickup optical unit 23 comprising the image pickup element 35 stored and disposed in an image pickup frame 31, the cover glass 34 and the centering glass 33 is stored in the outer case 37 formed of the rigid member and hardened and fixed with the adhesive, the outer case 37, in its bottom inside, may be disposed with a member softening the adhesive force of the adhesive, or the adhesive may be undergone by non-sticking treatment, so that this endoscope can absorb the tensile force by the contraction of the adhesive generated in the hardening process of the adhesive by the adhesive-force softened member or non-sticking treatment. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

The present invention relates to a side-view type endoscope apparatus, and in particular, imaging when an imaging optical unit disposed on the same optical axis as an objective optical unit is housed in an outer case and fixed with an adhesive to protect it from external force. The present invention relates to an endoscope apparatus in which peeling between an element cover glass and an imaging element centering glass does not occur.

2. Description of the Related Art Conventionally, endoscope apparatuses include a direct-view type that directly views an observation site in the insertion direction and a side-view type that laterally views an observation site in a direction perpendicular to the insertion direction.

The direct-view endoscope is arranged so that the insertion axis of the insertion portion and the optical axis of the objective lens are parallel to each other, and an imaging element is arranged at the imaging position of the objective lens to generate an observation site image signal. It has become. Alternatively, a prism is arranged at the exit end of the objective lens, and the imaging surface of the imaging device is arranged on the exit surface of the prism so that the imaging surface of the imaging device is arranged parallel to the insertion axis of the endoscope. (For example, refer to Patent Document 1).

Further, the side-view type endoscope apparatus has an objective lens arranged in a vertical direction orthogonal to the insertion axis of the insertion portion, a prism that converts outgoing light to a right angle at the outgoing end of the objective lens, and an outgoing end of the prism An image sensor is provided in the case. Alternatively, in order to reduce the diameter of the insertion portion, a prism is arranged at the observation optical entrance opening provided on the side surface of the insertion portion, and the objective lens is arranged parallel to the insertion axis of the insertion portion at the exit end of the prism. (For example, refer to Patent Document 2)
.
JP-A-6-70882 Japanese Patent Laid-Open No. 9-149883

As described above, in the endoscopic observation with the endoscope apparatus in which the objective optical system and the image sensor are arranged at the distal end of the insertion portion, the positions of the objective optical system and the image sensor are required to maintain a certain relationship. The objective optical system and the imaging element are solidified and fixed in the distal end of the insertion portion with an adhesive resin.

In the direct-view endoscope apparatus, the objective optical system is arranged so as to have an optical axis parallel to the insertion axis of the insertion section, and a subject and an obstacle in the insertion direction can be easily observed. Since the external force applied to the subject or the obstacle is relatively small, the positional relationship between the objective optical system and the image sensor can be maintained.

On the other hand, the side-view type endoscope apparatus is useful for observing the wall surface in the lumen to be observed, but rarely has a field of view in the insertion direction at the distal end of the insertion portion, so that the wall surface in the lumen is rarely used. May come into contact with an obstacle or may come into contact with another article before endoscopic observation.

The positional relationship between the objective optical system for the side view and the image sensor cannot be maintained due to contact with the wall surface or obstacle in the lumen, or contact with other articles before endoscopic observation, Damage occurs. For this purpose, the objective lens system and the image sensor are housed in an outer case formed of a rigid member and solidified and fixed with an adhesive resin.

In recent years, a compact lens having high lens performance has been developed and put into practical use as an objective optical system, and a charge coupled device (CCD) in which an image pickup device is also made small and has a high pixel has been developed and put into practical use. .

In a side-view type endoscope using such a small and high-performance objective optical system and an image sensor, and arranging the objective optical system and the image sensor on the same optical axis, the objective optical system and the image sensor due to external force In order to maintain the positional relationship, the positional relationship between the objective optical system and the image pickup device may not be maintained due to the solidification shrinkage of the adhesive when housed in an outer case made of a rigid member and solidified and fixed with an adhesive. is there.

In particular, when the imaging optical unit such as the imaging device, the cover glass of the imaging surface of the imaging device, and the centering glass of the imaging device is housed in the rigid exterior case and solidified with an adhesive, the adhesive is solidified. The tension | tensile_strength which the said image pick-up element cover glass and image pick-up element centering glass peel may arise by shrinkage | contraction.

When the cover glass and the centering glass are peeled off, the observation light transmitted through the peeled surface of the cover glass and the centering glass interferes, and the image generated by the interference observation light incident on the image sensor is unsightly and unclear. It becomes an image.

In addition, since the image pickup device is connected to the signal cable inserted through the flexible tube portion via a substrate having a drive control function, an external force is applied due to the deflection of the flexible tube portion and the signal cable. The image sensor cover glass and the image sensor centering glass may be peeled off.

The present invention has been made in view of such circumstances. When an image pickup device housed in an outer case of a rigid member is solidified and fixed with an adhesive, the cover glass of the image pickup device is obtained with an intellectual tension due to solidification shrinkage of the adhesive. It is an object of the present invention to provide an endoscope apparatus that prevents peeling of the centering glass and obtains a clear endoscopic observation image.

An endoscope apparatus according to the present invention is a side-view type endoscope apparatus that images and observes an observation region in a direction perpendicular to an insertion direction into a lumen, and a plurality of objective lenses are housed in a lens frame. An objective optical means and an optical element arranged on the same optical axis as the objective optical means, an image sensor, an image sensor cover glass,
And an imaging device in which an imaging element centering glass or the like is accommodated in an imaging frame, an exterior member formed of a rigid member that accommodates the imaging means, and the imaging optical means accommodated in the exterior member And a tension absorbing means for absorbing a tension applied to the imaging optical means due to shrinkage when the adhesive is solidified when the adhesive is filled and fixed.

The tension absorbing means of the endoscope apparatus according to the present invention is provided with a member for thinning the adhesive force of the adhesive that fills and penetrates between the bottom surface of the imaging means and the inside of the bottom surface of the exterior member. It is characterized by that.

In the endoscope apparatus of the present invention, the tension absorbing means is a non-adhesive processing of an adhesive applied to the inner bottom surface of the exterior member.

Further, the tension absorbing means of the endoscope apparatus according to the present invention is such that at least the imaging element centering glass of the imaging optical means can slide in the optical axis direction in accordance with the solidification shrinkage of the adhesive within the imaging frame. It is characterized by that.

With the endoscope apparatus of the present invention, an objective optical system for observing a wall surface in a lumen and an imaging optical system are arranged on a coaxial line, the imaging optical system is protected from external force by a rigid exterior case, In addition, peeling of the imaging optical system due to solidification shrinkage of the adhesive when the imaging optical system is fixed at the time of solidification can be prevented, and a clear endoscopic observation image can be obtained.

The endoscope apparatus according to the present invention has a cover glass for an image sensor due to solidification shrinkage of an adhesive when the imaging optical unit is housed and disposed in an exterior case and fixed to fix the adhesive in order to protect it from deformation and destruction due to external force. Thus, it is possible to provide an endoscope apparatus that can avoid peeling tension applied to the centering glass and that does not cause subject light interference.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. 1 is a cross-sectional view showing a configuration of an imaging apparatus provided at the distal end of an insertion portion of an embodiment of an endoscope apparatus according to the present invention, FIG.
FIG. 3 is a block diagram showing the overall configuration of an endoscope system incorporating an endoscope apparatus according to the present invention, and FIG. 3 is an imaging optical device provided at the distal end of an insertion portion of an embodiment of the endoscope apparatus according to the present invention. 4 is a cross-sectional view illustrating the relationship between the unit and the outer case, FIG. 4 is a cross-sectional view illustrating the arrangement of a mask used in the imaging optical unit of the endoscope apparatus according to the present invention, and FIG. 5 is a cross-sectional view of the endoscope apparatus according to the present invention. 6 is a cross-sectional view showing the configuration of the objective optical unit, FIG. 6 is a cross-sectional view showing the relationship between the imaging optical unit and the cable of the endoscope apparatus according to the present invention, and FIG. 7 is the configuration of the imaging frame of the endoscope apparatus according to the present invention. FIG.

First, an endoscope system incorporating an endoscope apparatus according to the present invention will be described with reference to FIG.

An endoscope system 1 includes an electronic endoscope 2 that is an endoscope apparatus according to the present invention, a light source device 3 that supplies illumination light to the electronic endoscope 2 via a universal cord unit 9, A video processor 5 connected to the electronic endoscope 2 via a scope cable 4 and performing drive control and video signal processing of an imaging device 24 described later built in the electronic endoscope 2, and the video processor 5 And a color monitor 6 for displaying a color video based on the video signal generated in (1).

The electronic endoscope 2 includes an elongated and flexible insertion portion 7 to be inserted into a lumen or the like, an operation portion 8 provided on the proximal end side of the insertion portion 7, and an extension from the operation portion. The universal part 9 is provided, and the scope connector part 10 is provided at the end of the universal part 9 and connected to the lighting device 3.

A connection connector portion 10a is provided on a side portion of the scope connector portion 10, and a connector 4a at one end of the scope cable 4 is connected to the connection connector portion 10a. The other end of the scope cable 4 is connected to the video processor 5 via a connector 4b.

The insertion portion 7 of the electronic endoscope 2 includes a distal end portion 11 incorporating an imaging device 24 to be described later, a bendable bending portion 12 formed on the proximal end side of the distal end portion 11, and the bending portion 12. And a long and narrow flexible tube portion 13 extending from the base end side to the operation portion 8.

The operation portion 8 is connected to the proximal end side of the flexible tube portion 13 of the insertion portion 13 and has a switch portion 14 having a plurality of switches 14a provided at the top, and an air supply /
An air supply / water supply control unit 15 that performs water supply control, a suction control unit 16 that performs suction control, a bending knob 17 that performs a bending operation of the bending portion 12 of the insertion unit 7 provided on a side surface, and the air / water supply control unit 15 And a gripping portion 18 provided on the lower side of the bending knob 17, a forceps insertion opening 19 b provided on the lower side of the gripping portion 18, and the like.

An air / water supply conduit (not shown) is provided from the insertion portion 7 to the inside of the operation portion 8, and the air / water supply conduit is connected to the air / water supply control portion 15 of the operation portion 8. In addition, it communicates with the scope connector portion 10 through an air / water supply conduit built in the universal cord portion 9 and is connected to an air / water supply mechanism built in the light source device 3. It has become.

The insertion portion 7 is provided with a suction conduit (not shown). The suction conduit is bifurcated in the vicinity of the distal end side of the operation portion 8 and one communicates with the forceps insertion port 19b. The other is connected to a suction base (not shown) of the scope connector portion 10 in communication with a suction pipe built in the universal cord portion 9 via the suction control portion 16.

Further, the suction conduit communicates with a distal end opening 19 a provided at the distal end portion 11 of the insertion portion 7. The tip opening 19a becomes a suction hole when driven by suction from the suction control unit 16, and becomes a forceps insertion opening through which a forceps treatment tool inserted from the forceps insertion hole 19b protrudes.

The distal end portion 11 is provided with an illumination window 20 and an observation window 21 in addition to the distal end opening 19a. The illumination window 20 and the observation window 21 are provided in a vertical direction perpendicular to the insertion axis direction of the distal end portion 11.

The illumination window 20 is provided with an exit end of a light guide fiber bundle. The light guide fiber bundle is built in the insertion portion 7, the operation portion 8, and the universal cord portion 9, and the incident end is provided in the scope connector portion 10. That is, the illumination light emitted from the illumination lamp of the light source device 3 is incident from the incident end of the light guide fiber bundle of the scope connector unit 10, guided by the light guide fiber bundle, and provided with the exit end. Is projected onto a subject that is an observation site in the lumen.

The observation window 21 is provided with an imaging device 24 described later, and a captured image signal of a subject illuminated with illumination light projected from the illumination window 20 is generated.

That is, the electronic endoscope 2 is a so-called side-view type electronic endoscope that observes a vertical direction orthogonal to the insertion direction when the insertion portion 7 is inserted into the lumen.

The configuration of the imaging device 24 built in the observation window 21 provided at the distal end portion 11 of the electronic endoscope 2 will be described with reference to FIG.

  The imaging device 24 includes an objective optical unit 22 and an imaging optical unit 23.

The objective optical unit 22 includes a plurality of objective lenses 26 a to 2 inside a cylindrical objective lens frame 25.
6d is fixed in a watertight manner with an adhesive 29 at a predetermined position. The most advanced objective lens 26 a of the objective optical unit 22 is disposed in the observation window 21. A second objective lens 26b is disposed on the emission surface side of the most advanced objective lens 26a through a mask. The subject light incident on the second objective lens 26b through the mask is projected onto the third objective lens 26c. The third objective lens 26c collects the incident subject light and projects it onto a cemented lens constituting the fourth objective lens 26d through a mask (hereinafter, the fourth objective lens 26d or This is referred to as a cemented lens 26d). The subject light collected by the fourth objective lens 26d is imaged on an image sensor 35 of the imaging optical unit 23 described later.

A spacing ring 27 having a mask is interposed between the third objective lens 26c and the fourth objective lens 26d, and the distance between the third objective lens 26c and the fourth objective lens 26d and the optical axis. Adjustments are made.

The imaging optical unit 23 has a cylindrical imaging frame 31 to which the outer periphery of the objective lens frame 25 of the objective optical unit 22 is attached and fixed, and a focal position of the objective optical unit 22 to which the imaging frame 31 is attached and fixed. An image pickup device 35 such as a CCD, a drive control of the image pickup device 35, and a substrate 41 having a function of processing a picked-up image signal generated by image pickup.

A cover glass 34 and a centering glass 33 are disposed on the front surface of the imaging region 35 a of the imaging element 35.
The mask 32 is tightly bonded with an adhesive having excellent light transmission characteristics.

The mask 32 projects subject light within a predetermined field of view condensed and emitted from the fourth objective lens 26 d of the objective optical unit 22 into the imaging area 35 a of the imaging device 35.

The centering glass 33 matches the imaging center of the imaging area 35 a of the imaging device 35 with the optical axis of the objective optical system unit 22.

The cover glass 34 prevents dust and the like from adhering to the surface of the imaging region 35a of the imaging device 35.

The respective surfaces of the centering glass 33, the cover glass 34, and the imaging region 35a of the imaging device 35 are tightly bonded with an adhesive having excellent light transmission characteristics.

On the inner wall surface of the imaging frame 31, the object light incident surface side of the centering glass 33 is mask 3
2, a jetty portion 31 b to be bonded and fixed is provided.

The image sensor 35 has inner leads 45 for transmitting and receiving drive control signals and image signals.
a is connected by a bump 45b.

  The inner lead 45 a is connected to the back surface copper foil pattern 41 c of the substrate 41.

The substrate 41 has a surface conductive pattern 4 formed on the surface of an insulating member 41b such as polyimide.
1a and a back surface conductive pattern 41c formed on the back surface. The surface conductive pattern 41a includes a control signal for driving and controlling the image sensor 35, an electronic component 42 having an image signal processing function for extracting and amplifying an image signal generated by photoelectric conversion by the image sensor 35, an integrated circuit element 43, and the like. Is installed. The back surface conductive pattern 41c is formed of the image sensor 35.
Is disposed along the back surface of the inner lead 45a and connected to the inner lead 45a.

Further, a plurality of signal lines 51 built in the cable 51 are provided on the base end side of the substrate 41.
a, 51b,... are connected. The cable 51 is connected to the video processor 5 via the insertion portion 7, the operation portion 8, the universal cord portion 9, and the scope cord 4. That is, the drive control signal of the image sensor 35 from the video processor 5 and the image signal generated by the image sensor 35 are transmitted and received via the signal lines 51a, 51b,.

The inner lead 45 a of the image sensor 35 is provided with a back surface copper foil pattern 41 of the substrate 41.
The outer periphery of the image sensor 35 to which c is connected and the cover glass 34 and the centering glass 33 are joined is sealed and fixed with a sealing resin 36a.

The imaging frame 31 in which the mask 32, the centering glass 33, the cover glass 34, and the imaging element 35 are accommodated is fitted and accommodated in an exterior case 37 formed of a rigid member such as metal.

The exterior case 37 includes an imaging frame storage portion 37a having a bottomed cylindrical shape into which the imaging frame 31 is fitted and stored, and an insulating member 41b of the substrate 41 by partially cutting the bottomed cylindrical arc. And the back surface copper foil pattern 41c are integrally formed in a shape including a bottomed rectangular substrate storage portion 37b formed in parallel to the substrate 41 from the opening.

That is, the imaging frame 31 is fitted and stored in the imaging frame storage portion 37a of the outer case 37,
A substrate 41 that is connected and extended to an image sensor 35 provided in the image frame 31 and has an electronic component 42 and an integrated circuit element 43 mounted thereon is accommodated in a substrate accommodating portion 37b.

The imaging element 35, the cover glass 34, the inner lead 45a, the insulating member 41b of the substrate 41, and the back surface copper foil pattern 4 in the imaging frame 31 fitted and housed in the exterior case 37.
The adhesive 36b is filled and solidified around the sealing resin 36a to which 1c is sealed and fixed, and around the substrate 41.

As described above, when the imaging optical unit 23 is stored in the exterior case 37 and then the adhesive 36b is filled and solidified, the imaging optical unit 23 can be firmly fixed in the exterior case 37, and an external case is applied when an external force is applied. 37 can protect the imaging optical unit 23.

The imaging optical unit 23 is accommodated in the exterior case 37 and solidified and fixed with an adhesive 36b, and then the substrate accommodation portion 37b and the cable are connected from the boundary between the imaging frame accommodation portion 37a and the substrate accommodation portion 37b of the exterior case 23. 51 is covered with a reinforcing frame 37c, and the outer periphery of the reinforcing frame 37c is covered with a heat-shrinkable tube.

After the imaging optical unit 23 is accommodated in the outer case 37 and filled with the adhesive 36b, the sealing resin layer 3 is contracted by the shrinkage of the adhesive 36b in the process of solidifying the filled adhesive 36b.
The image sensor 35 and the cover glass 34 sealed with 6a are pulled toward the bottom surface side of the outer case 37. On the other hand, the centering glass 33 is tightly bonded to the cover glass 34 with an adhesive, and is adhesively fixed to the jetty 31 b on the inner wall of the imaging frame 31.

That is, in the process of solidification shrinkage of the adhesive 36b, the image sensor 35 and the cover glass 34 sealed with the sealing resin 36a are pulled by the tension that is pulled toward the bottom surface of the outer case 37,
The cover glass 34 having the weakest bonding force and the centering glass 33 may be separated from each other.

Therefore, a sheet 38 such as a Teflon (R) sheet is placed on the bottom surface of the sealing resin 36 a of the image sensor 35. The sheet 38 has a thickness t1 (t> t1) that is thinner than the gap t between the sealing resin 36a of the imaging optical unit 23 and the bottom surface of the imaging frame storage portion 37a of the exterior case 37.
have.

After the sheet 38 having the thickness t1 is placed on the bottom surface of the sealing resin 36a, the imaging optical unit 23 is accommodated and the adhesive 36b is filled.
b is a gap (t−t1) between the sealing resin 36a of the imaging optical unit 23 and the sheet 38;
), But the adhesive strength is weak.

Thus, the sheet 38 is separated from the adhesive 36b due to solidification shrinkage of the adhesive 36b.

That is, since the filled adhesive 36b has a weak adhesive force with respect to the sheet 38 placed on the bottom surface of the sealing resin 36a, the solidification shrinkage of the adhesive 36b is absorbed by pulling the sheet 38 away from the adhesive 36b. Thus, peeling between the cover glass 34 and the centering glass 33 can be prevented. Therefore, the imaging optical unit 23 includes a centering glass 33, a cover glass 34,
In addition, the adhesive 36 is attached to the outer case 37 in a state where the image pickup surface of the image pickup element 35 is securely bonded.
It can be solidified and fixed with b.

In addition to the Teflon (R) sheet, the sheet 38 placed on the bottom surface of the imaging frame storage portion 37a of the exterior case 37 forms a gap that prevents the adhesive 36b from penetrating into the bottom surface of the imaging frame storage portion 37a. Sheets of other members that can be used may be used, and instead of the sheet 38, an elastic adhesive is applied, or the adhesive 36b is not bonded or a surface treatment is performed to reduce the adhesive force. Also good.

That is, when the adhesive 36b filled in the imaging frame storage unit 37 is solidified and contracted, a member that absorbs tension generated by the contraction and prevents the centering glass 33 and the cover glass 34 from peeling off, or Surface treatment is applied.

Further, instead of a process in which the sheet 38 provided on the bottom surface of the imaging frame housing portion 37a of the exterior case 37 or the elastic adhesive or the adhesive 36b is not adhered, the jetty of the imaging frame 31 of the imaging optical unit 23 is used. The adhesive 31 is accommodated in the outer case 37 without being bonded between the portion 31b and the centering cover 33 or temporarily fixed with an adhesive having a weak adhesive force.
When 6b is filled and solidified, the centering glass 3 is formed by the solidification shrinkage tension of the adhesive 36b.
3 can be absorbed in the direction away from the jetty 31b. Thereby, joining peeling of the said centering glass 33 and the cover glass 34 can also be avoided.

As described above, the imaging optical unit 23 is housed in the outer case 37 and solidified and fixed by the adhesive 36b, so that the imaging optical unit 23 can be protected against external force, and the outer case 37 can be solidified and fixed. The centering glass 33 and the cover glass 44 are not peeled off due to the solidification shrinkage of the adhesive 36b, and a clear subject image can be captured.

After the imaging optical unit 23 is housed and fixed in the exterior case 37, the objective lens frame 25 of the objective optical unit 22 is placed in the imaging optical unit 23 so that a subject image is formed in the imaging area 35a of the imaging element 35. The imaging frame 31 is attached and fixed.

As described above, in the endoscope apparatus of the present invention, the objective optical unit 22 and the imaging optical unit 23 are arranged on the same optical axis, and the imaging optical unit 23 is housed and filled in a rigid outer case 37. When the adhesive 36b is solidified and fixed, the contraction tension generated in the solidifying process of the adhesive 36b is absorbed in the direction of the optical axis of the imaging optical unit 23.
3 can be prevented from peeling off the centering glass 33 and the cover glass 34.

On the other hand, an image sensor 35 of the imaging optical unit 23 is connected to a cable 51 via a substrate 41.
The cable 51 is built in the bending portion 12 and the flexible tube portion 13. During endoscopic observation, the flexible tube portion 13 swings, and the built-in cable 51 also swings. The oscillation of the cable 51 is transmitted to the image sensor 35 via the substrate 41. That is, an external force due to the swing of the cable 51 is applied to the image sensor 35, and the cover glass 34 and the centering glass 33 are applied.
Sometimes peeled off.

As shown in FIG. 3B, the outer shape of the centering glass 33 of the conventional endoscope apparatus includes an imaging region 35a of the imaging device 35, and a substantially circular shape that protrudes from the four corners of the outer shape of the imaging device 35. Is formed. That is, the bonding area is set narrow so that the center of the imaging region 35a of the imaging device 35 and the center of the shape of the centering glass 33 are matched. Since the bonding area between the imaging element 35 and the centering glass 33 is narrow, the centering glass 33, the cover glass 34, and the imaging element 35 are peeled by the external force applied to the imaging element 35 due to the swing of the cable 51 described above. It was easy to occur.

On the other hand, the endoscope apparatus according to the present invention has a centering glass 3 as shown in FIG.
The outer shape 3 is formed so as to include the outer shape of the image sensor 35, thereby expanding the bonding area between the image sensor 35 and the centering glass 33.

Further, the optical center of the centering glass 33 is decentered with respect to the optical center of the imaging region 35 a of the imaging device 35. That is, the optical center of the centering glass 33 is set such that the distance A to the outer edge of the cover glass 34 on the substrate housing portion 37 b side of the outer case 37 is greater than the distance B to the outer edge of the cover glass 34 on the front end side of the outer case 37. It sets so that it may become large (A> B).

As a result, the bonding area between the centering glass 33 and the imaging device 35 is increased on the side where the substrate 41 and the cable 51 are provided, and when an external force due to the swinging of the cable 51 is applied,
Separation of the centering glass 33 and the image sensor 35 is made difficult to occur.

Further, as shown in FIG. 3C, the imaging region 35a of the imaging device 35 and the optical center of the centering glass 33 are not decentered, and the cable 51 is enlarged in the extending direction like the cover glass 34 '. To do. Alternatively, as shown in FIG. 3 (d), the same effect can be obtained by enlarging the cable 51 in the extending direction as a centering glass 33 ″.

A mask 32 is provided on the incident surface side of the centering glass 33 of the imaging optical unit 23. The mask 32 projects subject light within a predetermined visual field emitted from the objective optical unit 22 within the imaging region 35a of the image sensor 35, and shields subject light outside the visual field.

As shown in FIG. 4B, a conventional mask 32 ′ provided in the imaging optical unit 23 is formed using a sheet member having a certain thickness, and this mask 32 ′ is formed of the centering glass 33 ′. It is arranged on the incident surface.

The mask 32 ′ formed of a sheet member having a certain thickness as described above should block the subject light outside the field of view that is incident from the side surface of the opening that transmits the subject light.
Reflected on the side surface of the opening as indicated by arrows L1 'and L2' in the drawing according to the thickness of ', and the reflected light is incident on the imaging region 35a' of the imaging device 35 '. For this reason, unnecessary subject light outside the imaging visual field range is incident on the imaging region 35a ′ of the imaging element 35, and the captured image becomes unclear.

Therefore, as shown in FIG. 4A, a mask 3 is formed by vapor deposition on the exit surface side of the centering glass 33.
2a is formed, and the cover glass 34 is adhesively bonded to the exit surface of the centering glass 33 on which the mask 32a is formed. The same effect can be obtained even if the mask 32a is formed by vapor deposition on either the incident surface or the exit surface of the centering glass 33 or the cover glass 34.

Since the vapor deposition mask 32a is thin, the subject light L1 and L2 outside the visual field incident on the side surface of the opening 32b that transmits the subject light is not reflected, and the imaging element 3 is not reflected.
Only the subject light that has passed through the opening 32b formed by the vapor deposition mask 32a is incident on the fifth imaging region 35a.

In addition, the shape of the opening part 32b of the said vapor deposition mask 32a is made into the octagon shape which notched the four corners of the rectangle.

In assembling the imaging optical unit 23, conventionally, the mask 32 is placed and fixed on the jetty portion 31 b on the inner wall surface of the imaging frame 31, and the centering glass 33 is fixed to the placed and fixed mask 32. The cover glass 34 that is adhesively bonded to the imaging surface of the image sensor 35 is placed and fixed to the centering glass 33.

In such a procedure, the imaging frame 31 has a mask 32, a centering glass 33, a cover glass 34,
When the image pickup device 35 is housed, the optical center axes of the image sensor often shift.

Therefore, the center of the imaging area 35a of the imaging element 35 and the optical center of the centering glass 33 are aligned and bonded together in advance, and the center of the imaging area 35a of the imaging element 35 and the center of the inner diameter of the mask 32 are aligned. Adhesive bonding is performed on the incident surface of the centering glass 33.

In this way, the mask 32, the centering glass 33, the cover glass 34, and the image sensor 3
After joining and assembling 5, the imaging optical unit 23 in which the optical center axes coincide with each other can be generated by storing and arranging in the imaging frame 31.

Furthermore, the imaging frame 31 of the imaging optical unit 23 housed in the exterior case 37 is arranged.
The centering glass 33, the cover glass 34, and the image pickup element 35 are housed and arranged in a portion where a plurality of slits are provided in the axial direction as shown in FIG.
, 31f are formed.

That is, the insulating material 41b and the back surface copper foil pattern 41c extending from the substrate 41 are provided in a cylindrical portion in which the centering glass 33, the cover glass 34, and the imaging device 35 are accommodated and disposed inside the imaging frame 31. A plurality of arc side walls 31d, 3 separated by a plurality of slits at equal intervals in a cylindrical portion other than the opening slit 31c to be inserted and a cylindrical portion other than the opening slit 31c.
1e and 31f are formed.

The centering glass 33, the cover glass 34, and the image sensor 35 are accommodated in the inner peripheral portion where the circular arc side walls 31d, 31e, 31f are formed and sealed with a sealing resin 36a. When stored in the imaging frame storage unit 37a, the arcuate side walls 31d, 31e, 31f are arranged on the inner periphery of the imaging frame storage unit 37a of the outer case 37 as shown in FIG. In addition, spaces A, B, C between the sealing resin 36a and the circular arc side walls 31d, 31e, 31f
Are arranged evenly.

When the adhesive 36b is filled and cured in this state, the solidification shrinkage of the adhesive 36b can be absorbed by the slits between the arc side walls 31d, 31e, 31f. And the intervals A, B,
C is uniform, so that the balance of shrinkage can be maintained.
The imaging optical unit 23 can be housed and fixed in the outer case 37 without causing any peeling.

Further, as shown in FIG. 5B, the objective optical unit 25 ′ of the conventional endoscope apparatus has a plurality of objective lenses 26a ′ to 26d ′ accommodated in a substantially cylindrical objective lens frame 25 ′. Yes. A state-of-the-art objective lens 26a ′, a mask and a second objective lens 26b ′ are arranged from the front end side of the objective lens frame 25 ′. This state-of-the-art objective lens 26a ', the mask and the second objective lens 26b' specify the incident range of the subject light, that is, the visual field range.

On the inner wall of the objective lens frame 25 ′ on the emission end side of the second objective lens 26 b ′, there is a jetty 2
5'a is provided. The jetty 25′a holds and fixes the second objective lens 26b ′ and has a mask function for limiting the range of emitted subject light. This second
A third objective lens 26c ', a spacing ring 27', and a fourth objective lens 26d 'are arranged opposite to the objective lens 26b'.

The incident surface side of the third objective lens 26c ′ is brought into contact with the jetty portion 25′a, and is positioned on the exit surface side by a spacing ring 27 ′.

  The fourth objective lens 26d 'is also positioned and installed by the spacing ring 27'.

This spacing ring 27 'is on the same optical axis as the optical axes of the third objective lens 26c' and the fourth objective lens 26d 'and the optical axes of the most advanced objective lens 26a' and the second objective lens 26b '. And the third objective lens 26c ′ to the fourth objective lens 26d ′.
It also has a mask function for limiting the range of subject light emitted to the.

The fourth objective lens 26d ′ is a cemented lens in which the convex lens 26d′1 and the concave lens 26d′2 are adhesively joined. The subject light condensed by the fourth objective lens 26d ′ is the image sensor 3.
5 is projected onto the imaging region 35a. The fourth objective lens 26d ′ may be replaced with a convex lens 26d′1 and a concave lens 26d′2.

The third objective lens 26c ′ and the fourth objective lens 26d ′ are formed to have substantially the same outer diameter, and the third objective lens 26c ′ and the fourth objective lens 26d ′ are accommodated. The inner diameter l′ 1 of the objective lens frame 25 ′ of the portion is set so that the third and fourth objective lenses 26c ′ and 26d are formed.
It is formed in the same shape as the outer diameter of '.

However, the inner diameter l′ 1 of the objective lens frame 25 ′ where the third objective lens 26c ′ and the fourth objective lens 26d ′ are arranged has the third objective lens 26c in order to match the optical axis.
'And the fourth objective lens 26d' are slightly larger than the outer diameter, and there is a slight gap between the outer periphery of the third and fourth objective lenses 26c 'and 26d' and the inner peripheral wall of the objective lens frame 25 '. There is a gap.

With such a configuration of the objective lens frame 25 ', the field of view indicated by the dotted line arrows in the figure that are incident from outside the object light incident range of the state-of-the-art objective lens 26a' and the second objective lens 26b ', that is, from outside the field of view. The outside subject light is the most advanced, second and third objective lenses 26a 'and 26b'.
, 26c ′. The out-of-field subject light incident on the third objective lens 26c ′ is condensed and transmitted by the third objective lens 26c ′, and is emitted to the exit side spherical end surface of the objective lens frame 26c. The out-of-view subject light emitted to the inner wall is the third objective lens 26c.
The light is incident on the imaging region 35a of the image sensor 35 through a gap between the outer diameter of the spacing ring 27 'and the fourth objective lens 26d' and the inner wall of the objective lens frame 25 '.

Thereby, the captured image generated by the imaging element 35 is mixed with the out-of-view subject light, resulting in a blurred image.

Therefore, as shown in FIG. 5A, the objective optical unit 25 of the present invention has a distance ring 27 and a fourth objective lens 26d from the inner diameter l1 of the objective lens frame 25 in which the third objective lens 26c is arranged. A stepped portion 28 having a stepped dimension l (l = l2−l1) is provided by increasing the inner diameter l2 of the objective lens frame 25 in a portion where is disposed (l1 <l2).

When the interval ring 27 and the fourth objective lens 26d are arranged in the stepped portion 28, the object light outside the field indicated by the dotted line arrow in the drawing extends from the third objective lens 26c along the inner wall of the objective lens frame 25. Although it is emitted toward the fourth objective lens 26d side, the out-of-view subject light is emitted to the step portion 28 of the step l, so that it is difficult to be condensed by the fourth objective lens 26d. Further, by forming the spacing ring 27 with a light shielding member, the out-of-field subject light emitted from the third objective lens 26 c to the step l on the inner wall of the objective lens frame 25 is spaced at the step portion 28. Ring 2
Therefore, the out-of-field subject light can be prevented from entering the fourth objective lens 26d.

The fourth objective lens unit 25 is arranged in the objective lens frame 25 ′ of the conventional objective optical system unit 22.
As the objective lens 26d ′, a cemented lens in which a convex lens 26d′1 and a concave lens 26d′2 are adhesively bonded is used.

The cemented lens 26d ′ is set with the interval ring 27 ′ and the optical axis alignment with the third objective lens 26c ′. The convex lens 26 is positioned with the interval ring 27 ′.
The outer diameter of d′ 1 is approximately equal to the inner diameter of the objective lens frame 25 ′, and is fixed to the inner wall of the objective lens frame 25 ′.

Alternatively, although not shown, the convex lens 26d′1 on the light incident side of the cemented lens 26d ′.
Protruding portions that hold the outer periphery on the exit surface side are also provided in a ring shape from the inner wall of the objective lens frame 25.

On the other hand, the outer diameter of the concave lens 26d′2 on the light exit side of the cemented lens 26d ′ is equal to the convex lens 2.
It is smaller than the outer diameter of 6d′1, is not bonded and fixed to the inner wall of the objective lens frame 25 ′, and is bonded only to the exit surface of the convex lens 26d′1.

For this reason, when the cemented lens 26d ′ is bonded and fixed, the axis of the cemented lens 26d ′ is displaced.

Therefore, in the endoscope apparatus of the present invention, as shown in FIG. 5A, the cemented lens 26d, which is the fourth objective lens, is a convex lens 26d1, which is the side on which the positioning axis is aligned by the spacing ring 27.
The outer diameter of the convex lens 26 is formed smaller than the inner diameter l2 of the step portion 28 of the objective lens frame 25.
The outer diameter of the concave lens 26d2 joined to the exit surface of d1 is made equal to the inner diameter l2 of the step portion 28, and the outer diameter of the concave lens 26d2 is bonded and fixed to the inner wall of the step portion 28. As a result, it is possible to eliminate the separation of the cemented lens 26d and the misalignment of the shaft center when the cemented lens 26d is bonded and fixed.

Alternatively, although not shown, the concave lens 26d2 on the light emission side of the cemented lens 26d in FIG. 5A is not shown in order to strengthen the adhesion and fixation of the cemented lens 26d as the fourth objective lens in the objective lens frame 25. It is also possible to provide a convex portion that holds the outer periphery on the exit surface side in a ring shape from the inner wall of the objective lens frame 25, and sandwich the cemented lens 26 d between the convex portion and the spacing ring 27.

Further, as described above, in the conventional endoscope apparatus, the built-in cable 51 is swung by the swing of the flexible tube portion 13, and the swing is transmitted to the image sensor 35 through the substrate 41. As a result, the cover glass 34 and the centering glass 33 may be peeled off and the shaft core may be displaced.

Therefore, in the endoscope apparatus of the present invention, the plurality of signal lines 51a, 51b,... Of the cable 51 connected to the substrate 41 are the exterior case 31 or the imaging that is housed and fixed in the exterior case 31. The optical unit 23 or the center line 41 ′ in the axial direction of the substrate 41 connected to the imaging optical unit 23 is used as a reference, and the left and right parts are equally distributed.

That is, as shown in FIG. 6, signal lines 51 a to 51 f built in the cable 51 and connected to the electronic components 42 having various functions, the integrated circuit element 43, and the like formed on the substrate 41 are connected to the substrate 4.
The signal line connection lands are formed on the substrate 41 so as to be arranged and connected evenly from the center line in the axial direction of one.

Note that the positions of the signal line connection lands provided evenly on the substrate 41 are the signal lines 51 to be connected.
The number is set in consideration of the number of a to 51f (even number, odd number), line type (single wire, stranded wire, shielded wire, etc.), line thickness, and the like.

For example, since the power supply 51a and the ground line 51 for driving the image sensor 35 are single lines and thick, they are arranged with the center 41 ′ interposed therebetween. Further, the high frequency signal line 51b and the image output signal line 51e are arranged in the center 4 in order to reduce the influence of the crosstalk between the high frequency signal line 51b and the image output signal line 51e.
The substrate 1 was placed on the substrate 41 so as to have the greatest distance across 1 ′.

As a result, the substrate 4 is moved by the swing of the cable 51 built in the flexible tube portion 13 of the insertion portion 7.
Since the external force applied to 1 is equalized, the external force applied to the imaging optical unit 23 is also equalized, and the occurrence of failures such as optical axis misalignment of the imaging optical unit 23 and peeling of the cover glass 34 of the centering glass 33 is suppressed. it can.

Further, when the adhesive 34 is filled and solidified between the imaging optical unit 23 and the exterior case 37, the exterior case 37 and the imaging optical are arranged so that the filled adhesive 34 does not shrink in the exterior case 37. The gap between the units 34 is eliminated. Thereby, the tension applied to the imaging optical unit 23 due to the solidification process of the filling adhesive 34 can also be prevented.

[Appendix]
According to the embodiment of the present invention described in detail above, the following configuration can be obtained.

(Supplementary note 1) In a side-view type endoscope apparatus that images and observes an observation site in a vertical direction with respect to an insertion direction into a lumen,
An objective optical means in which a plurality of objective lenses are housed in a lens frame;
An image pickup means that is arranged on the same optical axis as the objective optical means, and that stores an image pickup device, an image pickup device cover glass, an image pickup device centering glass, and the like in an image pickup frame;
An exterior member formed of a rigid member that houses the imaging means;
A tension absorbing means for absorbing the tension applied to the imaging optical means due to shrinkage when the adhesive is solidified when the adhesive is filled and fixed around the imaging optical means housed in the exterior member;
An endoscope apparatus comprising:

(Additional remark 2) The said tension | tensile_strength absorption means inserted the member for thinning the adhesive force of the adhesive agent which permeate | penetrates between the bottom face of the said imaging means and the bottom face inside of the said exterior member, It is characterized by the above-mentioned. The endoscope apparatus according to appendix 1.

(Additional remark 3) The said tension | tensile_strength absorption means is the non-bonding process of the adhesive agent given to the bottom inner side of the said exterior member, The endoscope apparatus of Additional remark 1 characterized by the above-mentioned.

(Additional remark 4) The said tension | tensile_strength absorption means enabled at least image pick-up element centering glass of the said image pick-up optical means to be able to slide in an optical axis direction according to the shrinkage | contraction at the time of solidification of an adhesive agent in the said image pick-up frame. The endoscope apparatus according to appendix 1.

(Supplementary note 5) The endoscope apparatus according to any one of supplementary notes 1 to 4, wherein the imaging element centering glass of the imaging optical unit is formed so as to include an outer shape of the imaging element.

(Additional remark 6) The image pick-up element centering glass of the said image pick-up optical means was formed so that the junction area with the said image pick-up element might enlarge the area of the drawing-out side of the signal wire | line from an image pick-up element. 5. The endoscope apparatus according to 5.

(Additional remark 7) The endoscope apparatus in any one of additional remark 1 thru | or 6 with which the image pick-up element centering glass of the said imaging optical means vapor-deposited the mask in the light-projection surface.

(Additional remark 8) The said imaging optical means is attached to the imaging area of the said image pick-up element after joining an image pick-up element centering glass with the center axis | shaft of the imaging area of the said image pick-up element with respect to the image pick-up element to which the cover glass was joined. In addition, the endoscope apparatus according to any one of appendices 1 to 7, wherein a mask is joined to the imaging element centering glass.

(Supplementary note 9) The volume of the gap space formed between the imaging optical means and the exterior case means is made substantially the same when the imaging optical means is accommodated in the exterior case means. The endoscope apparatus according to any one of 1 to 8.

(Additional remark 10) The imaging frame of the said imaging optical means provided with the some slit between the said image pick-up element, an image pick-up element cover glass, and image pick-up element centering glass at least equipped internally, Additional remark 1 thru | or 9 characterized by the above-mentioned. The endoscope apparatus according to any one of the above.

(Supplementary Note 11) Out of a plurality of objective lenses of the objective optical means, an outer diameter of a final end objective lens is set larger than an outer diameter of an objective lens arranged on the incident side of the final end objective lens, and the lens frame The endoscope apparatus according to appendix 1, wherein a stepped portion is formed on the inner wall surface for accommodating the final end objective lens and the objective lens disposed on the incident side of the final end objective lens.

(Additional remark 12) The space | interval ring which sets the optical center of the last end objective lens is arrange | positioned in the level | step-difference part provided in the lens frame of the said objective optical means, The endoscope apparatus of Additional remark 11 characterized by the above-mentioned.

(Supplementary note 13) The endoscope apparatus according to supplementary note 12, wherein the spacing ring is formed of a light shielding member.

(Supplementary note 14) The endoscope according to any one of supplementary notes 11 to 13, wherein the final objective lens is formed of a cemented lens, and the lens on the emission side is cemented to an inner wall of the lens frame. apparatus.

(Additional remark 15) The endoscope apparatus of Additional remark 13 characterized by providing the convex-shaped part which hold | maintains the outer peripheral surface of the output surface of the lens by the side of the said joint lens in the objective lens frame inner wall.

(Supplementary note 16) Any one of Supplementary notes 1 to 15, wherein drive control of the imaging element of the pre-imaging optical means and a plurality of signal lines for transmitting and receiving an imaging signal generated and the like are arranged equally on the left and right Endoscopic device.

(Supplementary Note 17) The imaging optical means is housed and disposed, and a gap in which unnecessary tension is applied to the imaging optical means when the adhesive is solidified and contracted is eliminated between the exterior case means filled with the adhesive. Endoscopic device.

The sectional view showing the composition of the imaging device provided in the insertion part tip of one embodiment of the endoscope apparatus concerning the present invention. The block diagram which shows the whole structure of the endoscope system in which the endoscope apparatus which concerns on this invention was incorporated. Sectional drawing which shows the relationship between the imaging optical unit provided in the insertion part front-end | tip of one Embodiment of the endoscope apparatus which concerns on this invention, and an exterior case. Sectional drawing explaining arrangement | positioning of the mask used for the imaging optical unit of the endoscope apparatus which concerns on this invention. Sectional drawing which shows the structure of the objective optical unit of the endoscope apparatus which concerns on this invention. Sectional drawing which shows the relationship between the imaging optical unit of the endoscope apparatus which concerns on this invention, and a cable. The perspective view which shows the structure of the imaging frame of the endoscope apparatus which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 22 ... Objective optical unit 23 ... Imaging optical unit 24 ... Imaging device 25 ... Objective lens frame 26 ... Objective lens 27 ... Space ring 31 ... Imaging frame 32 ... Mask 33 ... Centering glass 34 ... Cover glass 35 ... Imaging element 37 ... Exterior Case 38 ... Sheet 41 ... Substrate Agent Patent Attorney Susumu Ito

Claims (4)

In a side-view type endoscope apparatus that images and observes an observation site in a vertical direction with respect to an insertion direction into a lumen,
An objective optical means in which a plurality of objective lenses are housed in a lens frame;
An image pickup means that is arranged on the same optical axis as the objective optical means, and that stores an image pickup device, an image pickup device cover glass, an image pickup device centering glass, and the like in an image pickup frame;
An exterior member formed of a rigid member that houses the imaging means;
A tension absorbing means for absorbing the tension applied to the imaging optical means due to shrinkage when the adhesive is solidified when the adhesive is filled and fixed around the imaging optical means housed in the exterior member;
An endoscope apparatus comprising: The tension absorbing means includes a member for thinning the adhesive force of an adhesive filling and penetrating between the bottom surface of the imaging optical means and the inside of the bottom surface of the exterior member. 1
The endoscope apparatus described. The endoscope apparatus according to claim 1, wherein the tension absorbing means is a non-bonding process of an adhesive applied to the inside of the bottom surface of the exterior member. The tension absorbing means is characterized in that at least the image sensor centering glass of the imaging optical means is slidable in the optical axis direction in accordance with contraction when the adhesive is solidified in the imaging frame. The endoscope apparatus according to 1.

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