JP3001035B2 - Optical adapter for endoscope - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical adapter for an endoscope, which is detachably connected to a distal end portion of an endoscope and enables observation in two viewing directions, a direct view and a side view.

[0002]

2. Description of the Related Art In recent years, an endoscope capable of observing internal organs in a body cavity by inserting an elongated insertion portion into the body cavity, and performing various treatments using a treatment tool inserted into a treatment tool channel as necessary. Is widely used. Also, in the industrial field, industrial endoscopes are widely used for observing and inspecting internal scratches and corrosion of boilers, turbines, engines, chemical plants and the like.

In the endoscope used as described above, an image pickup device such as a CCD is provided at the tip of an insertion portion, and an endoscope image formed on the image pickup device is projected on a monitor screen for observation by an electronic device. There is an endoscope.

US Pat. No. 5,122,650 discloses an electronic endoscope in which images obtained by two objective optical systems are formed on one CCD built in an insertion portion. Further, Japanese Patent Application No. 6-291602 proposes a distal end optical adapter or an endoscope adapter which is provided with a plurality of identical or different optical systems and is detachable from an endoscope.

[0005]

SUMMARY OF THE INVENTION Conventional direct view and side view 2
In an endoscope having two observation or imaging optical systems,
The side-view illumination lens is arranged on the front side or the rear side of the side-view imaging system with respect to the axial direction of the insertion section. For this reason, when it is disposed on the front side, the length of the hard portion becomes long, and a large difference is made between the optical path lengths for direct viewing and side viewing, which makes it impossible to use a common lens and increases the cost.

[0006] Further, if it is arranged on the rear side, a space for bending the side-viewing illumination system by 90 ° is required, and the outer diameter of the distal end becomes large. Further, in an endoscope that forms an image obtained by two objective optical systems on one CCD, the distance between the optical axes of the direct-view imaging optical system and the side-view imaging optical system cannot be so far apart. An illumination system for side viewing cannot be provided between two imaging optical systems.

The present invention has been made in view of the above points, and has both direct-viewing and side-viewing optical systems, can shorten the length of a hard part, and can share many lenses of both optical systems. An object of the present invention is to provide an optical adapter for an endoscope.

[0008]

According to the present invention, in order to achieve the above object, an endoscope which is detachably attached to a distal end portion of an endoscope and has two optical systems, a direct-view imaging optical system and a side-view imaging optical system. In the optical adapter for, in a cross section perpendicular to the axial direction of the insertion portion near the facing portion of the endoscope distal end portion, the illumination system for direct viewing is disposed on the side opposite to the side viewing direction of the side view imaging optical system, and A side-view illumination system is arranged on the side of the direct-view imaging optical system opposite to the side-view direction. Furthermore, the side-view illumination lens is located beside the first lens of the side-view imaging optical system, and the central axis of the direct-view imaging optical system is the central axis of the side-illumination light guide and the first axis of the side-view imaging optical system. It is located between.

With such a structure, both imaging optical systems and both illumination systems can be compactly arranged, the length of the hard end portion can be shortened without increasing the outer diameter, and the optical path of both imaging optical systems can be reduced. Since the lengths can be made substantially equal, many lenses can be used in common, and costs can be reduced.

[0010]

Embodiments of the present invention will be specifically described below with reference to the drawings. 1 to 7 relate to an embodiment of the present invention, FIG. 1 is an external view showing an external view of an endoscope system, and FIG. 2 is a perspective view of an optical adapter for an endoscope according to an embodiment of the present invention. 3 is a sectional view taken along the line CC of FIG. 6, and FIG.
6 is a sectional view taken along line DD of FIG. 6, FIG. 5 is a sectional view taken along line AA of FIG. 3, FIG. 6 is a sectional view taken along line BB of FIG. 3, and FIG. It is sectional drawing.

As shown in FIG. 1, an endoscope system 1 includes an endoscope 2 having built-in illumination means and observation means (imaging means).
A light source device 3 for supplying illumination light to the endoscope 2, and a camera control unit (hereinafter referred to as CCU) including signal processing means for image pickup means built in the endoscope 2.
4 and a monitor 5 as display means.

The endoscope 2 has a relatively large diameter, and is provided with an operating section 5 which is gripped by an operator and performs operations such as bending. The operating section 5 has a slender and flexible front end. The rear end of the insertion portion 6 having the following is continuously provided. The insertion section 6 has a hard distal end 9 provided on a distal end side of a flexible tube 7 having flexibility via a bendable section 8 which can be bent. The distal end optical adapter 10 of the embodiment as an optical adapter for an endoscope which can change an angle of view or a visual field direction or can observe two visual directions is detachably attached to the distal end portion 9. It has become.

The operating section 5 includes the bending section 8.
There is provided a bending operation knob 11 that bends a desired direction up, down, left and right. Further, a universal cord 12 is extended laterally from the operation unit 5, and a light source connector 13 connected to a distal end of the universal cord 12 is detachably connected to the light source device 3. Further, a CCU cable 14 extends from the light source connector 13, and a CCU connector 15 is connected to the end of the CCU cable 14.
The CU connector 15 is detachably connected to the CCU 4.

As shown in FIG. 3, an electric component 17 such as a CCD 16 and an IC, and a signal line cable 18 are adhered from the back of the CCD 16 to the cable connection portion with an adhesive inside a hard tip main body 21 forming the tip 9. There are provided an imaging unit 19 integrally molded and sealed, and two light guides 20 and 20 (only one is shown in FIG. 3) for transmitting illumination light. An adapter attachment / detachment screw portion 22 is provided on the outer peripheral surface of the tip end body 21. The tip optical adapter 10 is detachably attached to the adapter attachment / detachment screw portion 22 via a fixing ring.

As shown in FIG. 4, the optical system of the distal end optical adapter 10 and the endoscope 2 are opposed to each other by a positioning pin 23 provided on the distal end optical adapter 10 and a positioning groove 24 provided on the distal end body 21. Is positioned. That is, the two optical systems are connected in a positioned state by engaging the positioning pin 23 in the positioning groove 24.

The tip optical adapter 10 is an adapter body 25
And the cover 26, and the cover 26 is fixed to the adapter body 25 by an adhesive and screws 27 (see FIG. 4). In this embodiment, as shown in FIG. 2, two objective optical systems or imaging optical systems 28 and 29 are provided on the tip optical adapter 10 so that two objects are formed on one CCD 16 built in the tip portion 9. Is provided.

One is a direct-view imaging optical system 28 in which the observation direction of the objective optical system is directed in the forward direction parallel to the axis of the endoscope, and the other is the insertion section of the endoscope 2 in which the observation direction of the objective optical system is changed. 6 is a side-view imaging optical system 29 that is oriented in a direction perpendicular to the axial direction. When the bending operation knob 11 is operated so as to bend the bending portion 8 upward, it is set so as to face the side-viewing direction of the side-view imaging optical system 29, so this side-viewing direction is referred to as upward. .

The lens parts other than the rod lens 31 and the prism 32 constituting each of the imaging optical systems 28 and 29 are formed by using the same lens, so that the cost can be reduced by using a common lens. .
In the present embodiment, an endoscope adapter for observing direct vision and side vision is shown. However, in the endoscope system 1, in addition to this, there are other types of adapters for exclusive use of direct vision, for direct vision / direct vision (stereoscopic vision), and the like. An endoscope adapter can also be used.

The two light guides 20, 2 up to the tip 9
The illumination light guided by 0 is guided to a direct-view illumination system 33 and a side-view illumination system 34 for illuminating an observation direction corresponding to each of the imaging optical systems 28 and 29 in the tip optical adapter 10. In the present embodiment, the layout of the optical system is described below, and these optical systems are housed in the tip optical adapter 10 in a compact manner. Hereinafter, a more detailed description will be given with reference to FIGS.

As shown in FIG. 3, a CCD 1 protected by a cover glass is provided at a substantially central position (center in the left-right direction and slightly eccentric in the vertical direction) of the distal end surface of the distal end portion 9.
6, two light guides 20, 20 are symmetrically disposed below (the lower side in FIG. 3) (a light guide 20 shown in FIG. 3 and a lower side of the light guide 20 in a direction perpendicular to the paper surface of FIG. 3). Not a light guide).

The distal end surface of the distal end portion 9 is provided with a CCD of the distal end surface of the distal end portion 9.
An imaging optical system and an illumination optical system are formed such that a rear end of the imaging and illumination optical system is located at a position facing the light guide 16 and the light guides 20 and 20.

(As can be seen from the cross section taken along the line CC in FIG. 6)
As shown in FIG. 3, which is a cross section including the optical axis of the side-view imaging optical system 29, the lower side of the side-view imaging optical system 29 (in other words, the side opposite to the side-viewing direction) faces one light guide 20. The direct-view illumination system 33 is linearly arranged.

This side-view imaging optical system 29 is a first lens of a side-view imaging optical system (hereinafter, referred to as a first lens) attached to an upper side-view observation window.
Abbreviated as first lens in side view. And the prism 3 disposed on the optical axis of the first lens 36 for side view.
2, and a rear-viewing group lens 37 that is changed in a direction perpendicular to the prism 32 and is arranged along an optical axis parallel to the axis of the insertion section 6.

A direct-view illumination system 33 below the side-view imaging optical system 29 includes a cylindrical rod lens (or light guide) 38 disposed to face the light guide 20, and a distal end surface of the rod lens 38. And a direct-viewing illumination lens 39 attached to a direct-viewing illumination window facing the camera, and illuminates a visual field range corresponding to the angle of view of the direct-view imaging optical system 28.

A right-view imaging optical system 28 is disposed on the right side of the side-view imaging optical system 29. The direct-view imaging optical system 28 is a first-view first lens 41 attached to a front-view observation window on the distal end surface.
And a cylindrical rod lens 31 arranged opposite to the optical axis of the first direct-view first lens 41, and a direct-view rear group lens 42 disposed rearward facing the rod lens 31. . As shown in FIG. 4, the common CCD 16 passes through the rear-viewing side group lens 37 and the direct-viewing rear group lens 42 arranged adjacent to the front surface (imaging surface) of the CCD 16.
Are formed on the left and right imaging area portions of the imaging surface.

Further, as shown in FIG.
9 (for example, the rearmost lens of the rear group lens 37) and some of the lenses of the direct-view imaging optical system 28 (for example, the rearmost lens of the rear group lens 42) cut the inner side adjacent in the left-right direction. D-shaped non-circular and common C
An image is formed over a wide range on the imaging surface of the CD 16.

Direct-view imaging optical system 28 and side-view imaging optical system 29
Are not crossed, for example, by a partition 55 integrated with the adapter body 25. Also, BB in FIG.
As can be seen from the cross-sectional view of FIG. 6, a side-view illumination light guide 43 constituting the side-view illumination system 34 is disposed below the direct-view imaging optical system 28. The side-view illumination system 34 extends below the direct-view imaging optical system 28 in a direction parallel to the axis of the insertion portion 6, and has a rear end facing the front end surface of the light guide 20. The light guide 43 includes an illumination light guide 43 and a side-view illumination lens 44 attached to a side-view illumination window facing the bent distal end surface of the light guide 43.

The light guide 43 is formed so as to be three-dimensionally bent from under the direct-view imaging optical system 28 to outside the direct-view imaging optical system 28 and to the vicinity of the side-view illumination lens 44. The field of view is illuminated according to the angle of view of the system 29. More specifically, as shown in FIG. 6, the distal end side of the light guide 43 is bent radially outward so as to surround the direct-view imaging optical system 28 and extends to the upper side-viewing illumination window side. A side view observation window is formed adjacent to the illumination window side.

In the present embodiment, in the distal end optical adapter 10 in FIG. 3, a cross section taken along the line AA perpendicular to the axis of the insertion portion at the facing portion facing the distal end portion 9 and near the distal end portion 9 is shown in FIG. As shown in the figure, (the light guide 43 of) the side-view illumination system 34 is disposed on the opposite side of the side-view imaging optical system 28 from the side-view direction, and the direct-view illumination system 33 is provided below the side-view imaging optical system 29. (Rod lens 38) is arranged.

Incidentally, as shown in FIG.
The central axis of 8 is arranged between the central axis of the side-view imaging optical system 29 and the bent portion 43a of the light guide 43 for side-view illumination. The side-view illumination light guide 43 is bent toward the side-view imaging optical system 29 in order to prevent illumination unevenness at the time of near-point observation (bent so as to face obliquely upward beyond the upward direction which is the side-view direction). )ing. The side-view illumination lens 44 is disposed so as to partially overlap the direct-view imaging optical system 28 with an offset.

In this embodiment, the direct-view imaging optical system 28
In the first embodiment, the cover 26 is provided with a first lens 41 for direct viewing, and the adapter body 25 is provided with a lens system after the rod lens 31 as a second lens. In the case of such a structure, light leaked from the side-view illumination light guide 43 and the direct-view illumination rods lens (or light guide) 38 passes through the first lens 41.
The structure must be such that it does not penetrate between the lens and the second lens and does not cause flare.

In the case where the cover 26 and the adapter body 25 are in close contact with each other to prevent light from entering, very high-precision processing is required, and the cost is increased. Also,
A step is provided between the cover 26 and the adapter body 25 and loosely fitted,
If the illumination light is prevented from directly entering, the structure becomes complicated and the cost increases.

In order to solve the above-mentioned problem, in the present embodiment, the first viewing optical system 28 of the
A light blocking member 45 is provided at the rear end of the lens 41. The light blocking member 45 is adhesively fixed to the outer periphery of the rod lens 31 and further loosely fits with the cover 26.

As shown in FIG. 7, the light shielding member 45 is made of an elastic body such as rubber, resin, or the like, and is provided on the outer periphery of the rod lens 31, and the cover 26 and the adapter body 2 are provided.
The intrusion of the illumination light from the gap 5 may be prevented.
By adopting such a structure, it is possible to prevent the illumination light from entering the direct-view imaging optical system with a simple structure and without increasing the cost.

According to the present embodiment, two modes of direct view and side view are provided.
An adapter having two optical systems. In a section perpendicular to the axial direction of the insertion portion near the portion facing the distal end of the endoscope, the side-view illumination system 34 is disposed below the direct-view imaging optical system 28 and the side-view imaging optical system. The direct-view illumination system 33 is located below the system 29.

Further, the side-view illumination lens 44 is located beside the first lens 36 for the side-view imaging optical system,
The central axis 8 is located between the central axes of the side-view illumination light guide 43 and the side-view imaging optical system first lens 36.

With such a configuration, both the imaging optical systems 28 and 29 and both illumination systems 33 and
When the endoscope 2 is used as the endoscope 2 in a state in which the distal end optical adapter 10 is mounted on the hard distal end portion 9, the distal end side hard portion (the distal end optical adapter 10 and the distal end portion) can be stored. 9) The length, that is, the length of the tip hard portion can be shortened. In this case, since it can be arranged compactly, it is possible to avoid an increase in the outer diameter.

Further, both the direct-viewing and side-viewing imaging optical systems 28,
Since the optical path lengths of the imaging optical systems 29 can be made substantially equal, many of the lenses of the two imaging optical systems 28 and 29 can be shared, and the cost can be reduced.

Next, an embodiment of an endoscope which solves the problem from another viewpoint will be described. This endoscope will be described first with reference to a background in which a tip optical adapter containing two imaging optical systems is connected to a tip portion containing one solid-state imaging device.

In an endoscope optical system adapter (hereinafter referred to as an adapter) for changing the angle of view and depth of an observed image of an industrial endoscope used for inspection of pipes and the inside of a machine, the watertightness of an imaging optical system is ensured. In addition, it is necessary to seal the lens and a hole for accommodating the lens (hereinafter referred to as a lens hole) by some means.

In the case where images from two imaging optical systems are formed on one solid-state imaging device (CCD or the like), a method using an all-circular lens for the imaging optical system (for example, US Pat. Since the lens hole is circular, the lens serves as a sealing member for hermetic sealing.

However, in US Pat. No. 5,122,650, since the two images do not intersect (the light beams of both optical systems do not intersect), as shown in FIG. 12, the image is projected on the imaging surface 62 of the solid-state imaging device. Range 63, 63
Becomes smaller. That is, only an image with a low resolution can be obtained.

Therefore, by using a non-circular lens in which a part of the lens constituting the imaging optical system or a plurality of parts is cut, a large image, that is, a high-resolution image, which effectively utilizes the imaging surface of the solid-state imaging device is projected. Will be able to do it. FIGS. 13 and 14 show this state.

As shown in FIG. 13, for example, by using non-circular lenses 64, 64 cut into a D-shape, images can be formed in a wide range 65, 65 on the imaging surface 62.

The D-shaped non-circular lens 64 shown in FIG.
The other side of the lens 64 is also cut to form a non-circular lens 6 as shown in FIG.
Also in the case where 6 and 66 are used, images can be formed in a wide range 65 and 65 on the imaging surface 62 as in FIG.

However, when a non-circular lens is used, the lens frame naturally needs a non-circular lens hole having the same shape as the lens in order to ensure watertightness.

When machining this non-circular lens hole, special machining such as electric discharge machining is required, and the cost of parts increases.

Further, since it is necessary to bond the plurality of lenses at the rearmost end of the image pickup optical system to each other in a watertight manner, it takes much time for assembling.

An object of the present embodiment is to provide an endoscope having an adapter which is non-circular and has a plurality of image pickup optical systems and which can be manufactured at a low cost. In order to achieve this, an endoscope with one solid-state imaging device is attached to the insertion end of the endoscope, and the angle of view and the depth of the observation image are changed. Place a water-resistant transparent sealing member (eg, glass) large enough to cover the lens hole including the escape portion of the blade other than the lens hole, such as a wire cutter, at the final end of the imaging optical system of the adapter, and adhesively fix it. The endoscope is an adapter that secures a sealed structure.

Hereinafter, the present embodiment will be described with reference to FIGS. 8 is a vertical cross-sectional view of the distal end portion of the endoscope and the adapter from the side, FIG. 9 is a vertical cross-sectional view of the distal end portion of the endoscope and the adapter from the top side, and FIG. 10 is an adapter along line EE in FIG. FIG. 11 is a cross-sectional view (when the partition is integral with the adapter main body), and FIG. 11 is a cross-sectional view of the adapter along the line EE in FIG. 8 (when the partition is separate from the adapter main body).

The overall configuration of the endoscope 2 of the present embodiment is shown in FIG.
In the following, description will be made on the case of the endoscope provided with the adapter of the first embodiment of FIGS. 2 to 7, and the same members as those of the first embodiment will be described with the same reference numerals. .

As shown in FIGS. 8 and 9, a distal end hard member 21 is provided at the distal end portion 9 of the insertion section 6 of the endoscope 2, and includes a solid-state imaging device 16, an electric component 17, and a signal line cable 18. Built-in imaging unit 19. Further, a light guide 20 is provided adjacent to the imaging unit 19.

The adapter 10 attached to the distal end portion 9 is composed of an adapter body 25 and a cover 26. The adapter body 25 and the cover 26 are fixed with an adhesive and screws 27 in a watertight manner.

The distal end portion 9 of the insertion portion 6 of the endoscope 2 is provided with an adapter attaching / detaching screw portion 22. The adapter 10 is screwed, and the distal end hard member 21 and the adapter main body 25 are attached and mounted. Is done.

The positioning of the distal end 9 and the adapter 10 in the rotation direction is performed by using the positioning groove 2 provided in the distal end hard member 21.
4 and positioning pins 23 provided on the adapter 10.

As shown in FIGS. 9 and 10, lens holes 51a and 51b are formed in the adapter body 25 so as to be adjacent to each other, and both the lens holes 51a and 51b are formed as shown in FIGS. A circular hole (sealing member hole) 52 for accommodating a sealing member 53 of a size that can be covered is provided, and the direct-view imaging optical system 28 and the side-view imaging optical system 29 are provided.
Is stored, and then the disk-shaped transparent sealing member 53 can be housed and sealed. FIG.
As shown in FIG. 0, the lens holes 51a and 51b are provided with blade reliefs 54 used to drill the lens holes 51a and 51b, respectively.

Direct-view imaging optical system 28 and side-view imaging optical system 29
Are not crossed by the partition 55.
8 and 9 show a case where the partition 55 is formed integrally with the same member as the adapter body 25. In this case, the cross section taken along line EE in FIG. 8 is as shown in FIG. On the other hand, when the partition 55 is formed of a member different from the adapter main body 25, the cross section taken along line EE in FIG. 8 is as shown in FIG.

The light beam entering from the first lens 41 of the direct-view imaging optical system 28 passes through each optical element (the cylindrical rod lens 31 and the rear group lens system 42) of the direct-view imaging optical system 28,
An image is formed on the left half area of the solid-state imaging device 16. The light ray entering from the first lens 36 of the side-view imaging optical system 29 passes through each optical element (prism 32 and rear group lens 37) of the side-view imaging optical system 29 and forms an image on the right half area of the solid-state image sensor 16. I do.

As shown in FIG. 10, a part of the lens (for example, the rear group lens 37) of the side-view imaging optical system 29 and a part of the lens (for example, the rear group lens 42) of the direct-view imaging optical system 28 are adjacent in the horizontal direction. Cut out the inside of each of them (disposed facing each other) and use a common C
An image is formed over a wide range on the imaging surface of the CD 16.

The adapter body 25 and the cover 26 are provided with a direct-view illumination system 33 and a side-view illumination system 34 such that the rear end is located at a position facing the light guide 20 at the distal end portion 9. The observation ranges of the direct-view imaging optical system 28 and the side-view imaging optical system 29 are respectively illuminated.

The direct-view illumination system 33 includes a rod lens (or light guide) 38 and a direct-view illumination lens 39 attached to a direct-view illumination window facing the distal end surface of the rod lens 38.

The side-view illumination system 34 includes a side-view illumination light guide 43 disposed below the direct-view imaging optical system 28 and a side-view illumination window opposed to the bent distal end surface of the light guide 43. And an attached side-viewing illumination lens.

Next, the operation will be described. The sealing member 53 is water-tightly bonded to the adapter body 25 so as to cover the lens holes 51a and 51b.

In addition, the imaging optical systems 28, 2
9 first lenses 41 and 36, illumination system lenses 39 and 44
Are watertightly adhered to the cover 26, so that the two imaging optical systems 28 and 29 of the adapter 10 are hermetically sealed.

Even if there is an escape portion of the blade, water sealing can be ensured by the sealing member 53, so that low-cost processing such as an end mill and a wire cutter can be performed, and the cost of parts can be reduced. Also,
Since only one sealing member for ensuring watertightness is required, no cost is required. Further, since only one assembly and one sealing member are required to be bonded, the assembling time is reduced.

Although the endoscope 2 of the present embodiment has been described in the case where the imaging optical systems 28 and 29 for direct and side viewing are partially formed by non-circular lenses, the endoscope 2 is formed by non-circular lenses. The present invention can also be applied to a case of a stereoscopic adapter or the like provided with two of the above-described two direct-view imaging optical systems.

According to the endoscope 2 of the present embodiment, by using a sealing member having a size capable of covering the lens hole, it is possible to provide an endoscope provided with a low-cost adapter. .

[Supplementary Notes] An endoscope optical adapter detachably attached to an endoscope end portion and having two optical systems, a direct-view imaging optical system and a side-view imaging optical system, wherein an insertion portion near an opposing portion to the endoscope end portion is provided. In a cross section perpendicular to the axial direction, a direct-view illumination system is arranged on the side opposite to the side-view direction of the side-view imaging optical system, and a side-view illumination system is arranged on the side opposite to the side-view direction of the direct-view imaging optical system. An optical adapter for an endoscope, characterized in that:

2. In a cross section perpendicular to the axial direction of the insertion portion, the side-view illumination lens is located beside the first lens of the side-view imaging optical system, and the central axis of the direct-view imaging optical system is the side- view illumination light guide and the side-view illumination light guide. 2. The endoscope optical adapter according to claim 1, which is located between the central axes of the first lens of the imaging optical system.

3. 2. The endoscope optical adapter according to claim 1, wherein a lens other than the direct-view rod lens and the side-view prism is common. 4. An endoscope optical adapter is composed of at least two parts, a cover and a main body. In an endoscope provided with a first lens on the cover side and a second lens and thereafter on the main body side, between the first lens and the second lens. 2. The endoscope optical adapter according to claim 1, further comprising a light shielding member. 5. 5. The endoscope optical adapter according to claim 4, wherein the light shielding member is an elastic body such as rubber or resin.

6. In an endoscope with a solid-state imaging device built in at the tip of the insertion section, it has a plurality of imaging optical systems attached to the end of the endoscope and uses a non-circular lens. At the final end of the imaging optical system of the leading optical adapter that can convert, etc., a water-resistant transparent sealing member large enough to cover the hole for housing the imaging optical system is covered and fixed with adhesive. An endoscope having a tip optical adapter. 7. 7. The endoscope according to claim 6, wherein in two sets of imaging optical systems partially using D-shaped lenses, the cut surfaces of the lenses are arranged to face each other.

[0072]

As described above, according to the present invention, there is provided an optical adapter for an endoscope having two optical systems, a direct-view imaging optical system and a side-view imaging optical system, which is detachably attached to the distal end of the endoscope. In a section perpendicular to the axial direction of the insertion portion near the end portion facing the endoscope distal end portion, a direct-view illumination system is arranged on the side opposite to the side-view direction of the side-view imaging optical system, and the direct-view imaging optical system Since the side-view illumination system is disposed on the side opposite to the side-view direction, both imaging optical systems and both illumination systems can be compactly stored in the endoscope optical adapter, and the length of the hard part can be shortened. The optical path lengths of the imaging optical system can be made substantially equal, and many lenses can be shared.

[Brief description of the drawings]

FIG. 1 is an external view showing the external appearance of an endoscope system.

FIG. 2 is a perspective view of an optical adapter for an endoscope according to one embodiment of the present invention.

FIG. 3 is a sectional view taken along line CC of FIG. 6;

FIG. 4 is a sectional view taken along the line DD of FIG. 6;

FIG. 5 is a sectional view taken along line AA of FIG. 3;

FIG. 6 is a sectional view taken along line BB of FIG. 3;

FIG. 7 is a cross-sectional view near a first lens of a direct-view imaging optical system according to a modification.

FIG. 8 is a longitudinal sectional view of the distal end portion of the endoscope and the adapter viewed from the side.

FIG. 9 is a longitudinal sectional view of the distal end portion of the endoscope and the adapter from the upper surface side.

FIG. 10 is a sectional view of the adapter taken along line EE in FIG. 8 when the partition is integrated with the adapter body.

11 is a cross-sectional view of the adapter taken along line EE in FIG. 8 when the partition is separate from the adapter body.

FIG. 12 is an explanatory diagram showing a state where an image is formed on an imaging surface of a solid-state imaging device by two imaging optical systems in a conventional example.

FIG. 13 is an explanatory diagram showing a state in which lenses constituting two imaging optical systems in FIG. 12 are imaged on an imaging surface by a non-circular lens cut into a D shape.

FIG. 14 is an explanatory diagram showing a state in which an image is formed on an imaging surface by non-circular lenses in which both right and left sides of lenses constituting two imaging optical systems in FIG. 12 are cut.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Endoscope system 2 ... Endoscope 3 ... Light source device 9 ... Tip part 10 ... Tip optical adapter 16 ... CCD 20 ... Light guide 21 ... Tip part main body 25 ... Adapter body 26 ... Cover 28 ... Direct-view imaging optical system 29 ... side-view imaging optical system 31 ... rod lens 32 ... prism 33 ... direct-view illumination system 34 ... side-view illumination system 36 ... side-view first lens 39 ... direct-view illumination lens 41 ... direct-view first lens 43 ... side-view illumination Light guide 44 ... side view illumination lens

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G02B 23/26

Claims (2)

(57) [Claims] 1. An endoscope optical adapter detachably attachable to an endoscope distal end portion and having two optical systems of a direct-view imaging optical system and a side-view imaging optical system, wherein the optical adapter is opposed to the endoscope distal end portion. In a cross section perpendicular to the axial direction of the insertion section near the section, a direct-view illumination system is arranged on the side opposite to the side-view direction of the side-view imaging optical system, and the side opposite to the side-view direction of the direct-view imaging optical system. An optical adapter for an endoscope, wherein a visual illumination system is arranged. 2. In a cross section perpendicular to the axial direction of the insertion portion,
The side-view illumination lens is positioned beside the first lens of the side-view imaging optical system.
And the central axis of the direct-view imaging optical system is the side-view illumination light.
Position between the guide and the central axis of the first lens of the side-view imaging optical system.
The optical adapter for an endoscope according to claim 1, wherein the optical adapter is disposed.