JPH07311348A - Plural visual field-direction type endoscope - Google Patents

Abstract

PURPOSE:To provide a plural visual field-direction type endoscope constituted so that there is not a movable part at the tip part and the image transmission part of the endoscope, the structure of the tip part is simple and the assembling performance thereof is excellent, an image is not deteriorated in the peripheral part and sterilization resistance is excellent by specially considering the deterioration of the sterilization resistance, the assembling performance and the picture. CONSTITUTION:The endoscope 11 is obtained by arranging an objective optical system 22 having plural visual field directions and forming one image on the tip thereof and provided with a relay lens system 23 transmitting the image or a pupil corresponding to the plural visual field directions by continuing the optical system 22. At the back part of the lens system 23 of the endoscope 11, an eyepiece optical system 24 is arranged. At the back part of the optical system 24, a camera for picking up the object images whose visual field directions are different at the position of the plural pupils P3 can be arranged.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an endoscope, and more particularly to a multi-view direction endoscope having a plurality of view directions.

[0002]

2. Description of the Related Art Japanese Unexamined Patent Publication (Kokai) No. 57-200125 discloses an endoscope which can be viewed by switching between direct-view and side-view directions. As shown in FIG. 15, the objective optical system includes an optical system 89 in the direct-viewing direction and an optical system 90 in the side-viewing direction. These optical axes are combined by a half mirror 91 and superposed as one image. ing. That is, the images formed by any of the optical systems are the same as the subsequent optical system 9
It can be handed over to 2. There are two ways to change the view direction. One of the means is to switch the illumination irradiation direction toward the direction of direct view or side view to the direction to be observed. Further, the other means is provided with a light-shielding member 93, 93 provided on the object side of the prism for both direct view and side view and capable of electrically switching transmission / blocking of light. One is observable.

Japanese Unexamined Patent Publication No. 2-32313 discloses an endoscope which has two visual field directions and uses polarized light for conversion of the visual field directions. In this endoscope, in order to realize two visual field directions as shown in FIG. 16, a polarizing device 96 is provided between two prisms 94 and 95 for combining light rays from the two visual field directions, and the respective visual fields are provided. Direction images are transmitted through the relay lens system as linearly polarized light orthogonal to each other, and one of the viewing directions is mechanically and electrically rotated by 90 ° at the base end of the endoscope. You can select and observe.

In Japanese Patent Laid-Open No. 2-156923, there is shown in FIG.
The arthroscope shown in 7 (a) is shown. That is, in this arthroscope, an optical path forming two visual field directions is formed by three prisms 97, 98, 99, and the center of the pupil of the objective optical system corresponding to each visual field direction is shown in FIG. The common planes are arranged in the lateral direction at the positions 100 and 101. Then, by moving the position of the optical system behind the prism within the range of the arrow shown in FIG. 9B, one of the pupils can be selected to switch the visual field direction.

[0005]

SUMMARY OF THE INVENTION The above-mentioned endoscope having an electric and mechanical visual field direction switching device at the distal end portion and the image transmitting portion has a complicated structure, which deteriorates the assembling property. When polarized light is used to switch the viewing direction, linear polarized light is transmitted as it is in the vicinity of the optical axis by passing through a lens system behind the polarizing device, but rotation of the polarization axis occurs in the peripheral area. In the peripheral image, images from different viewing directions leak and image deterioration occurs.

Further, an endoscope, particularly a rigid endoscope, is exposed to high temperature steam of 100 ° or more for sterilization. Therefore, a rigid endoscope having a movable part has a problem in durability.

The present invention has been made by paying attention to the drawbacks of the assembling property and the deterioration of the image as described above, and there is no movable part in the tip portion and the image transmitting portion of the endoscope, and the structure of the tip portion is simple. It is an object of the present invention to provide a multi-viewing direction endoscope which is easy to assemble and does not show image deterioration in the peripheral portion.

The present invention has been made by paying attention to the deficiency of sterilization resistance as described above, and there is no movable portion at the distal end portion of the endoscope and the image transmitting portion, and the multi-viewing direction type internal endoscope having excellent sterilization resistance is provided. The purpose is to provide an endoscope.

According to the present invention, a plurality of object images corresponding to a plurality of visual field directions can be simultaneously observed or selectively observed so that a plurality of object images corresponding to a plurality of visual field directions can be observed. An object of the present invention is to provide a multi-viewing direction endoscope that can provide object images without overlapping.

[0010]

The invention according to claim 1 is
A plurality of visual field directions and a plurality of pupils corresponding to these visual field directions and arranged so as not to overlap with each other;
Alternatively, the objective optical system for forming two or more object images and the size equal to or larger than the size of the plurality of pupils from the objective optical system are formed, and the object image from the objective optical system and the plurality of pupils are formed. And a transmission optical system for transmitting backward.

According to a second aspect of the present invention, in the multi-view direction endoscope according to the first aspect, there are a plurality of pupils respectively corresponding to the light beams from the plurality of different directions, and the pupils are formed by the transmission optical system. A plurality of pupils that are separated from each other, and an imaging optical system that forms an object image formed by a light beam included in the range of the separated pupils corresponding to the respective visual field directions. There is.

According to a third aspect of the present invention, there is provided an objective optical system having a plurality of visual field directions and a plurality of pupils corresponding to the visual field directions and formed so as not to overlap each other, and an objective optical system for forming an object image. A multi-viewing direction endoscope having a single optical axis and a transmission optical system for transmitting an object image from the objective optical system and a plurality of pupils, wherein the objective optical systems are different from each other. A front optical system for injecting a light beam from a direction and emitting the light beam as a plurality of substantially afocal light beams arranged in parallel substantially parallel to each other along the optical axis of the transfer optical system; A rear optical system having one optical axis and converging a plurality of light beams from the front optical system to form an object image rearward, and the transfer optical system includes a plurality of rear optical systems. Size equal to or larger than the size of multiple pupils corresponding to the luminous flux It is formed, and to transmit the object image and a plurality of pupils from the rear optical system backward.

According to a fourth aspect of the present invention, there is provided an objective optical system having a plurality of visual field directions and a plurality of pupils corresponding to the visual field directions and formed so as not to overlap each other, and to form a plurality of object images. And a transmission optical system having a single optical axis, wherein the objective optical system makes light beams incident from different visual field directions enter the transmission optical system. A front optical system that emits a plurality of substantially afocal light beams that are arranged substantially parallel to each other along the optical axis of the system, and a plurality of emitted light beams from the front optical system, respectively, to converge a plurality of object images to the rear side. A plurality of rear optical systems arranged in parallel to form a plurality of objective images respectively, and the transfer optical system has a size that a plurality of pupils corresponding to a plurality of light beams from the rear optical system have. Is formed to a size equal to or larger than Transmitting the plurality of object images and a plurality of the pupil from the serial plurality of posterior optical system backward.

According to a fifth aspect of the present invention, there is provided an objective optical system having a plurality of visual field directions and a plurality of pupils corresponding to the plurality of visual field directions, and a transfer optical system having a single optical axis. A multi-view direction endoscope, wherein the objective optical system comprises:
Front including a plurality of pupils that respectively enter a plurality of light beams from different directions, and a prism optical system that changes at least one optical path of the light beams to convert each light beam into a light beam that is directed in substantially the same direction An optical system and a rear optical system that forms an object image composed of a plurality of light fluxes from the front optical system at substantially the same position, and the transfer optical system includes an object image from the rear optical system and a plurality of object images. The eyes of the person are transmitted backward.

According to a sixth aspect of the present invention, there is provided an objective optical system having a plurality of visual field directions and a plurality of pupils corresponding to the plurality of visual field directions, and a transfer optical system having a single optical axis. A multi-view direction endoscope, wherein the objective optical system comprises:
A plurality of lenses having optical axes in mutually different directions, and prism optics for receiving each light flux transmitted through the plurality of lenses and converting the light flux into a plurality of light fluxes arranged substantially in parallel along the optical axis of the transmission optical system. A front optical system including a system and a size including a light beam emitted from the front optical system, and a plurality of light beams are simultaneously imaged on an image plane. A rear optical system having a converging property, and the transfer optical system transfers the object image from the rear optical system and the plurality of pupils rearward.

According to a seventh aspect of the present invention, there is provided an objective optical system having a plurality of visual field directions and a plurality of pupils corresponding to the plurality of visual field directions, and a transmission optical system having a single optical axis. A multi-view direction endoscope, wherein the objective optical system comprises:
A front optical system including a pupil dividing unit that divides the pupil into a plurality of pupils, a prism member that makes incident directions of light beams corresponding to the divided pupils different from each other, and a plurality of lenses having optical axes in different directions. , A rear optical system having a single optical axis for simultaneously forming a plurality of light beams on the image plane and having a convergent property with respect to an outgoing light beam, and the transfer optical system includes a rear optical system from the rear optical system. The object image and the plurality of pupils are transmitted backward.

According to an eighth aspect of the present invention, there is provided an objective optical system comprising a plurality of visual field directions, a plurality of pupils corresponding to these visual field directions, and an optical system for forming an image at the same position by a light beam from each pupil. Is included.

A ninth aspect of the present invention includes a plurality of front optical systems including a lens having a negative refractive power and an objective optical system including a rear optical system having a convergent property and including a lens having a positive refractive power. A field-of-view endoscope, wherein the front optical system is provided with a plurality of lenses having optical axes in different directions, and optical axes of a transmission optical system that receives light beams from different directions and transfers the light beams. And a prism for converting into a plurality of light fluxes arranged substantially parallel to each other, the rear optical system has a size including the light flux emitted from the front optical system and a single optical axis, and a plurality of light fluxes simultaneously Form an image of an object on the image plane.

[0019]

A multi-viewing direction endoscope according to any one of claims 1 to 7 includes an objective optical system having a plurality of visual field directions and a plurality of pupils corresponding to the visual field directions, and the objective optical system. A transfer optics of said one or more images and said plurality of pupils, said transfer optics being compared with the size of said plurality of pupils formed in said transfer optics from said objective optics. The object image and the pupil are formed to have substantially the same size or more, and the object image and the pupil are transmitted rearward without vignetting. That is, it is possible to obtain a plurality of pupils that do not overlap behind the transmission optical system, and a plurality of visual field directions corresponding to the pupils are simultaneously provided. For this reason, JP-A-2-15692
Unlike Japanese Patent Publication No. 3, it is not necessary to provide a movable part in the transmission optical system for selecting the visual field direction.

Further, there are a plurality of visual field directions and one-to-one correspondence in the visual field directions.
The objective optical system having a plurality of pupils corresponding to is used.
Therefore, the present endoscope has a plurality of pupils corresponding to one-to-one in the visual field direction as in the technique disclosed in JP-A-57-200125 and JP-A-2-323313, It is not necessary to provide a field-of-view direction switching means such as a light blocking means and a polarizing means in front of the pupil in the objective optical system, and the structure of the objective optical system is simplified and the assembling property is improved.

Further, since the endoscope according to any one of claims 1 to 7 does not use polarized light, it is disclosed in JP-A-2-32313.
The image in the peripheral portion does not deteriorate due to the rotation of the polarization direction as in the publication.

Here, of the one or more object images in claim 1, one object image and the object images of the claim lights 3, 5, 6 and 7 are images from a plurality of pupils. It is a thing. It does not have to be exactly the same, and the area is made to substantially overlap only at the image forming position to reduce the area, and when the observer's pupil is placed at any of the plurality of pupil positions transmitted by the transmission optical system. The viewing direction can be selected. It is also possible to arrange the imaging means at the position of this pupil. Further, since the area is made small, when the image pickup means is arranged at the image position, by blocking the light rays other than the light rays forming the necessary image at the pupil position, the viewing direction can be selected without moving the image pickup means. Is possible. In addition, according to the first to seventh aspects, since it is possible to selectively observe a plurality of images corresponding to a plurality of visual field directions, it is possible to simultaneously provide a plurality of objective images corresponding to a plurality of visual field directions.

The plurality of pupils in the fourth aspect are substantially overlapped on the same plane.

A multi-view direction endoscope according to claim 2 is
A plurality of object images corresponding to a plurality of visual fields can be simultaneously obtained from the light flux separated by the pupil separating means by the image forming optical system. Therefore, in the endoscope described in this section, it is easy to selectively observe the object images corresponding to a plurality of visual fields with the naked eye and to provide the image signal by capturing each object image by providing the image pickup means. Is. In the endoscope described in this section, since there is no need to use the above-mentioned movable part or polarized light in the endoscope, the endoscope has excellent resistance to high temperature due to sterilization.

The multi-viewing direction endoscope according to the eighth and ninth aspects does not require a transmission optical system itself for selecting a viewing direction unlike the conventional example, and corresponds to the viewing direction one to one. It is unnecessary to provide a visual field direction switching unit such as a light blocking unit or a polarizing unit before the pupil in the objective optical system as compared with the case where the plural pupils are not provided, and the structure of the optical system is simplified. Assembleability is improved.

[0026]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 3 relate to the first embodiment, and FIG.
1A is a configuration diagram of a multi-viewing direction endoscope, FIG. 1B is a diagram showing a configuration example of a brightness diaphragm, FIG. 2 is an overall configuration diagram of an endoscope device, and FIG. 3 is pupil division. It is a block diagram which concerns on the design example of the objective optical system which utilized this.

An endoscope apparatus 10 shown in FIG. 2 has an endoscope 11 which has an insertion portion 2 and whose view direction is variable, and a camera 4.
And a monitor 5 and a light source device 7.

In the endoscope 11, the distal end portion 1 of the insertion portion 2 is incorporated with an objective optical system having a plurality of visual field directions and a light guide for illuminating each visual field direction.
Following the objective optical system, the insertion section 2 is provided with a relay lens system which is an optical system for transmitting an image and a pupil. An eyepiece optical system is arranged on the base 3 of the endoscope 11, and a camera 4 can be attached behind the eyepiece optical system. Here, the base portion 3 and the camera 4 of the endoscope 11 are configured as an integral type or a detachable type. The subject imaged by the camera 4 is finally displayed on the monitor 5 as an endoscopic image so that the observer can observe it.

Illumination light from the light source device 7 passes through the light guide cable 6, passes through the base portion 3, the insertion portion 2 and the tip portion 1 and illuminates each visual field direction.

Next, details of the optical system of the endoscope 11 will be described. Regarding the optical system of the endoscope of the first embodiment,
The objective optical system uses pupil division and is an example of a configuration having an eyepiece optical system.

The pupil division method is basically composed of an optical system having one optical axis, but since it is of a plural visual field direction type, a lens corresponding to plural visual field directions is provided in front of the optical system. A group will be arranged. A multiple visual field direction type optical system adopting this pupil division method has the same configuration in the plural visual field directions in order from the object side, and the front lens group arranged facing each visual field direction, A prism for forming images from a plurality of viewing directions in the latter stage of the front lens group corresponding to the viewing direction, and a brightness diaphragm having a plurality of apertures arranged in the vicinity of the pupils to form a plurality of pupils. , A rear lens group that forms light beams from a plurality of visual field directions into a single superimposed image. Originally, the light flux of one optical system is divided in the vicinity of the pupil by the aperture stop 21 having two apertures shown in FIG.
The light flux passing through one of the openings is directly viewed as it is, and the light flux passing through the other opening of the aperture stop 21 is viewed in a perspective view by a prism. Here, two images in the visual field directions are formed to overlap each other on the image plane.

The configuration of the optical system according to this embodiment will be specifically described with reference to FIG. The optical system shown in FIG. 1A is composed of an objective optical system 22, a set of relay lens systems 23 as a transmission optical system, and an eyepiece optical system 24.

The objective optical system 22 is provided with two objective lenses 25 and 26 which are arranged at a position closest to the object and which respectively face in the direct-viewing direction and the side-viewing direction, and the light flux from the two objective lenses 25 and 26. Is incident on different surfaces, a second prism 28 on which the light flux from the first prism 27 is incident on the same surface, and a diaphragm 21 for dividing the pupil into a plurality of portions corresponding to the visual field direction. And a rear lens group 29b for converging the light flux from the pupil and forming an objective image behind the front lens group 29a. In the figure, the alternate long and short dash line indicates each visual field direction, that is, the optical axis of the objective lenses 25 and 26.

An image in the direct viewing direction is formed by this optical system as follows. The light ray that has passed through the direct-viewing objective lens 26 passes through the surface 31 of the first prism 27, and then the cemented surface 3
Up to 2. The joint surface 32 on the side of the first prism 27 is coated with black so as to prevent passage of rays other than effective rays in order to prevent harmful flare, and forms a flare stop. First and second prism 2
Since 7 and 28 are made of the same glass material, they have the same refractive index and pass through the surface 28 without refraction. Thereafter, the lower side of the aperture stop 21 is used as a pupil plane, and the rear lens group 29b forms an image I1 with the optical axis of the rear lens group 29b as the central axis.

On the other hand, the image in the perspective direction is formed as follows. The light ray that has passed through the oblique-viewing objective lens 25 reaches the cemented surface 32 after passing through the surface 33 of the first prism 27.
At this time, the light rays forming the image in the oblique direction go straight on the cemented surface without being refracted as in the case of the direct-viewing light rays. The joint surface 32 on the side of the first prism 27 is a flare diaphragm that allows only effective light rays to pass in order to prevent harmful flare. Since the optical axis in the direct viewing direction and the optical axis in the oblique direction intersect at the joint surface, the same flare diaphragm effectively functions for light rays from both directions. The light ray from the oblique direction that has traveled straight is reflected by the mirror-processed surface 34 and reaches the surface 32 on the second prism 28 side again. The surface 32 on the side of the second prism 28 is mirror-processed within a range in which the direct-view light rays and the oblique light rays separated by pupil division are not vignetted and in which the oblique light rays reflected by the surface 34 are covered. Therefore, the rays from the perspective direction which are reflected by the surface 34 without being eclipsed pass through the upper side of the aperture stop 21 and are then transmitted by the rear lens group 29b in the same manner as the direct-view rays, with the optical axis of the rear lens group 29b as the central axis. The formed image I1 is formed.

The images I1 and the pupil 21 from a plurality of visual fields formed by the objective optical system 22 are formed by the relay lens system 2
It is transmitted in the direction of the eyepiece optical system by 3. Reference numeral P2 in the drawing indicates a plurality of pupils corresponding to the respective visual field directions transmitted by the relay lens. An image I2 is formed between the relay lens system 23 and the eyepiece optical system 24, and the eyepiece optical system 24
Through, a plurality of pupils P3 corresponding to each visual field direction can be obtained.

The observer can select the visual field direction by moving the position of his / her pupil to the position of the transmitted pupil in the visual field direction to be observed.

In this embodiment, the objective optical system is originally designed as a coaxial optical system, and is not a decentered optical system. It has a structure in which it is bent by a prism with respect to pupils having different viewing directions. That is, the objective lens 2 is placed on the line extending the optical axis of the rear lens group 29b through the cemented surface 32.
There are 6 optical axes, and the optical axis of the objective lens 25 is on the extension line where the optical axis of the rear lens group 29b is reflected by the cemented surface 32 and further reflected by the reflective surface 34. Therefore, even if the light beam is not afocal between the optical system including the two negative lenses and the prism and the optical system behind the optical system, two images that are overlapped in front of the relay optical system are formed. be able to.

Since pupil division is used in this embodiment,
Since it is originally one optical system, good image quality can be obtained with a small number of lens configurations, and the means for determining a plurality of pupils can be set at the position of the pupil P2 of the relay system 23 as long as it is a position conjugate with the pupil position of the objective optical system. Other parts may be used, and since the objective optical system and the transmission optical system do not have a device for switching the visual field direction,
It has a simple structure and is easy to assemble.

FIG. 3 shows an actual design example of the objective optical system, and Table 1 shows its numerical data. In the structure shown in FIG. 3, the portion shown as the rear lens group 29b in FIG. 1 is composed of three cemented lenses 29 '.

[0041] As described above, in the configuration of the present embodiment, the following effects can be obtained by adopting a configuration in which only one image is formed. That is, the objective optical system of the multiple-viewing-direction endoscope has a plurality of viewing directions and a plurality of pupils corresponding to the viewing directions one by one, and one image, and one image is an image in the plurality of viewing directions. Are overlapped with each other, and the optical axes of multiple visual fields coincide with the optical axis of the transfer system at the image position. The image and the plurality of pupils are transmitted without vignetting.

Therefore, in this embodiment, the visual field direction can be selected behind the transmission optical system, and the objective optical system and the transmission optical system for selecting the visual field direction do not require a movable portion. Further, in this embodiment, since the objective optical system and the like do not have a device for switching the visual field direction, the structure is simple and the assembling is good. Further, since polarized light is not used, the image in the peripheral portion is not deteriorated by the rotation of the polarization direction.

These effects are the same when the pupil dividing means is provided in the transmission optical system or the image forming optical system.

FIGS. 4 to 9 relate to the second embodiment of the present invention, and FIG. 4A is a configuration diagram of a multi-viewing direction endoscope including an objective optical system using a decentered optical system. FIG. 6B is a configuration diagram of an endoscope according to a modified example of the second embodiment, FIG. 5 is a configuration diagram of an objective optical system that uses a decentered optical system, and an afocal portion is partially common, and FIG. FIG. 7 is a block diagram of an objective optical system that uses a decentered optical system and achieves a perspective view by refraction, FIG. 7 is a configuration diagram of a design example of an objective optical system that uses a decentered optical system, and FIG. FIG. 9 is a configuration diagram according to a design example in which a relay lens system is combined, and FIG. 9 is a front view of an objective optical system having three viewing directions.

The endoscope of this embodiment uses a decentered optical system as an objective optical system, and uses an image forming optical system and a solid-state image sensor instead of the eyepiece optical system of the first embodiment. It does not have a general visual field direction selection means.

FIG. 4A shows the configuration of the optical system arranged inside the endoscope of this embodiment. The optical system of this endoscope has an objective optical system 41, a relay lens system 42, an imaging lens 43, and a pupil separation optical member 44c in order from the tip side.
And reflection members 44a and 44b such as mirrors, two lens systems 45a and 45b, and two solid-state image pickup devices 46a and 46b as image pickup means. Although only one relay lens system is shown, it goes without saying that a plurality of relay lens systems may be used if necessary. Also, the imaging lens 4
5a and 45b constitute the above-mentioned image forming optical system.

The objective optical system 41 has a substantially afocal lens group 47 which is independent of each other and has two visual field directions of a front group and a strabismus and a pupil P11 corresponding to these visual field directions.
A front optical system 47 composed of a and 47b is arranged, and the rear group has a size capable of transmitting the light beams from the plurality of pupils P11 to the image without being eclipsed, and the light beams from the plurality of visual field directions overlap each other. A rear lens system 48 is arranged which forms one image I11.

The relay lens system 42 forms an image of the pupil P11 as a pupil P12 and an image I11 as an image I12, which is transmitted to the image forming lens 43. The imaging lens 43 transmits the image and the pupil transmitted from the relay lens system 42 to the side of the pupil separating optical member 44c having a plurality of reflecting surfaces, and the pupil separating optical member 44c receives the plurality of pupils P13, In different directions, that is, the reflecting members 44a, 44
It is designed to be separated and sent to b. In the reflecting members 44a and 44b, the separated pupils, in the illustrated example, two pupils corresponding to the optical system in the direct viewing direction and the optical system in the oblique direction are respectively reflected toward the lens systems 45a and 45b, respectively, The lens systems 45a and 45b are adapted to form an image corresponding to each pupil on the solid-state image pickup devices 46a and 46b.

In the above-mentioned structure, first, the light rays in each visual field direction pass through the two lens groups 47a and 47b which are substantially afocal constituting the front optical system 47, and then the rear lens system 48 causes the light rays in each visual field direction. The axis is bent and the image I11 is imaged on the optical axis of the rear lens system 48. In this embodiment, in realizing the perspective direction, the one having the same basic configuration as the one realizing the perspective performed by the prisms 27 and 28 of the first embodiment is used. Here, the perspective prism is described in JP-A-60-140313,
JP-A-50-91333 and JP-A-2-10801
A 30 ° prism shown in Japanese Patent Laid-Open No. 3-9, JP-A-59-87.
70 ° prism or 110 shown in Japanese Patent No. 403
A prism or the like may be used.

Further, as the objective optical system 41, as shown in FIG. 5, a front optical system 47c including prisms similar to the prisms 27 and 28 of the embodiment is used, that is, the direct-viewing and oblique-viewing optical systems are shared. May be. Alternatively, in the objective optical system 41, as shown in FIG. 6, a wedge prism 49 may be placed in the vicinity of the pupil P1 to realize a perspective view by utilizing refraction. In this configuration, the lens groups used in the direct-viewing direction and the oblique-viewing direction can use substantially the same lens groups only with different lengths. In addition, the wedge prism 49 is arranged behind the wedge prism 49. Alternatively, the objective optical system 41
As shown in FIG. 9, three or more viewing directions may be provided as long as the relay lens system arranged behind does not cause vignetting of an image or pupil. In the example shown,
The lenses 50, 51, 52 on the frontmost side are shown, each of which is 0.
A lens group of 30 degrees (squint), 30 degrees (squint), and 70 degrees (squint) is formed.

The light flux from the objective optical system 41 is shown in FIG.
As shown in (a), the relay lens system 42 forms an image I12 behind the relay lens system as in the first embodiment. The light rays from the respective visual field directions forming the image I12 formed behind the relay lens system 42 are generated by two pupil light fluxes having different visual field directions by the pupil separation optical member 44c arranged behind the imaging lens 43. Each is separated. The pupil separation optical member 44c is, for example, a prism arranged near the position of the pupil P13 transmitted by the relay lens system 42 and imaged by the imaging lens 43. The separated luminous fluxes in the respective visual field directions are reflected by the reflecting members 44a and 44b, respectively, and are imaged on the image pickup devices 46a and 46b via the lens systems 45a and 45b.

In this embodiment, the image forming lens 4 for forming an image on the pupil is formed.
3, the optical axis is made substantially parallel to the optical axis of the relay lens system 42, and the object point is imaged at infinity. The images may be formed so as not to overlap one solid-state image sensor.

According to this embodiment, with the above-described structure, the plurality of solid-state image pickup devices can independently pick up images in different visual field directions, and the number of visual fields and the visual field directions can be easily selected by the objective optical system. An optical visual field direction switching means is not provided, and images in all visual field directions are taken in and imaged. In the configuration using a plurality of solid-state image pickup elements as shown in the figure, each switch is performed by switching the switch. Select the output of the image sensor,
Display and the like can be performed by performing predetermined signal processing. Further, in the case of the configuration using one solid-state image pickup device, each image having a different visual field direction may be selected by the signal processing means connected to the subsequent stage. Then, an image in only one visual field direction can be displayed on the monitor.

In other words, in this embodiment, the visual field direction conversion can be realized without moving the optical system or optically switching the visual field direction. Further, depending on how the signal processing is performed, it is possible to simultaneously display a plurality of images in the visual field direction on one or a plurality of monitors.

A design example of the objective optical system is shown in FIG.
A design example in which the objective optical system and the relay lens system are combined is shown in FIG. 8, and R (radius of curvature of lens surface), d
The data (distance between each surface), n (refractive index), and V (Abbe number) are shown in Table 2-1 and Table 2-2. In the figure, reference numeral 54 is an objective optical system, and reference numeral 55 is a relay lens system. Table 2-2
Is a series of tables that follow Table 2-1.

[0056] Incidentally, the diaphragm for determining the pupil may be the objective optical system or the pupil position in the conjugate relay system, as in the first embodiment.
Alternatively, it may be a pupil position near the pupil division optical member.

FIG. 4 (b) shows a modification of the second embodiment. In this modification, a pupil image forming lens 56 provided in place of the image forming lens 43 forms a pupil image P3 as a divergent light beam or a convergent light beam, and then a lens 57 for making the light beams parallel forms an afocal light beam. Then, this light flux is further transmitted through the imaging lenses 45a and 45b to the image pickup elements 46a and 4a.
The image is formed on 6b. In this modification, the reflection prism as the pupil division optical member is unnecessary. The diaphragm may be arranged at the pupil position in the figure, may be arranged in the relay lens system, or may be arranged at the pupil position of the objective optical system. Other configurations and operations similar to those of the second embodiment are designated by the same reference numerals and description thereof will be omitted.

10 to 13 relate to the third embodiment of the present invention. FIG. 10 is a block diagram of a multi-viewing direction endoscope having a pupil switching device, and FIGS. 11 (a) and 11 (b) are image rotators. FIG. 13 is a configuration diagram of a multiple-viewing-direction endoscope in which the viewing directions can be switched according to FIG. 12, and FIG. 13 is a configuration diagram of a multi-viewing direction endoscope in which a pupil switching device is provided near the pupil of the objective optical system, FIG.
(B) is a block diagram of a multiple visual field direction endoscope different from (a).

The structure of the third embodiment has an image forming optical system and a solid-state image pickup element as in the second embodiment, and further has a means for switching the optical visual field direction.

The objective optical system of the present embodiment may be either the pupil division system of the first embodiment or the substantially afocal plural optical systems of the second embodiment and the rear optical system. This embodiment is different from the above-mentioned embodiments in the configuration of the optical system and the like arranged behind the relay lens system arranged behind the objective optical system.

As shown in FIG. 10, the optical system of the present embodiment is a light beam which is formed as a divergent light beam in each visual field direction after being imaged once by the relay lens system behind a relay lens system (not shown). A lens system 61 for making the light beam parallel to the optical axis of the relay lens, and a light flux in each visual field direction, which is arranged in the vicinity of the pupil imaged through the lens system 61 and is parallel to each pupil. A pupil switching device 62 as a selection means for switching between the two, and an imaging lens system 63 for focusing the light beam selected by the pupil switching device 62 on a solid-state image sensor 64.
And have.

The rays of light in the respective visual field directions forming the image I21 formed behind the relay lens system are made parallel by the lens system 61 to the optical axis of the relay lens system. The switching device 62 near the pupil position blocks light rays passing through the pupil other than the visual field direction that the observer wants to observe. The blocking means as the selecting means may mechanically move the light shielding plate,
You may use the on / off of the switch of a liquid crystal shutter. Alternatively, as the selection means, the selection means shown in FIGS.
The image rotator 65 may be moved to switch the viewing direction. Reference numeral 66 is an image forming lens system for forming an image of the light beam obtained by the image rotator 65 on the solid-state image pickup device 64. The figures (a) and (b) are
It is shown that the image rotator 65 is moved to switch the visual field direction.

Alternatively, as the selection means, FIG.
As shown in, the imaging lens system 65 and the solid-state imaging device 64 may be integrally moved to a position in the visual field direction to be observed, and the visual field direction may be switched. Only the image in the selected visual field direction is formed on the solid-state image sensor 64.

The effect of this embodiment is that the viewing direction conversion can be realized in a small space.

When the pupil and the image formed by the objective optical system are transmitted by the relay lens system and the pupil dividing means is arranged after the relay lens system, the aperture stop 2 of the first embodiment is used.
1 can be omitted.

Although the structures of the second and third embodiments have the image pickup means, they can be applied to an external camera connectable to the eyepiece optical system of the first embodiment. In this case, the lens system 43 or 61 is replaced with the eyepiece optical system 24.

Further, the optical system after the transfer optical system combined with the one using the pupil division of the objective optical system and the one using the decentering optical system has an eyepiece optical system and a means for switching the optical visual field direction. You can choose anything you don't have.

In either case of utilizing the pupil division in the objective optical system of the present invention or utilizing the decentering optical system, a means for blocking light rays in the direction other than the visual field required near the pupil in each visual field direction is provided. By providing the endoscope, a variable viewing direction endoscope can be realized even if the transmission optical system is replaced with a solid-state image sensor or an image guide. The configuration shown in FIG. 13A has a pupil near the pupil formed in the optical path of an objective optical system 70 including a front lens group similar to the front lens group 29a of the first embodiment and the rear lens system 48. In this example, the switching device 68 is provided and the solid-state imaging device 69 is arranged. Pupil switching device 68
A liquid crystal shutter or the like is preferable. The configuration shown in FIG. 13B uses the decentering optical system 71 including the same optical system as the front optical system 47c shown in FIG.

FIG. 14A is a block diagram of the optical system of the multiple-viewing direction endoscope according to the fourth embodiment, and FIG. 14B is a block diagram of an objective optical system that is partially common. .

The objective optical system of the fourth embodiment is composed of a plurality of lens groups provided for each visual field instead of the objective optical system 22 of the first embodiment, and a plurality of images are formed by this lens group. It is configured to. Other configurations and operations similar to those of the first embodiment are designated by the same reference numerals and description thereof will be omitted.

The objective optical system 73 shown in FIG. 14A is composed of a plurality (two in the illustrated example) of independent lens groups. Behind the objective optical system 73, the relay lens system 23 and the eyepiece optical system 24 are arranged. still,
The relay lens system 23 and the eyepiece optical system 24 may be configured in place of the imaging optical system and the solid-state image sensor.

The objective optical system 73 may be constituted by an independent optical system as shown in FIG. 14 (a), or a part, that is, a tip end, like the objective optical system 73 'shown in FIG. 14 (b). The side lens may be shared.

A plurality of images I31, I formed by the objective optical system
32 is transmitted rearward by a relay lens system 23 as a transmission optical system. With the configuration including the eyepiece optical system 24, as shown in FIG. 14A, an observer can view the respective visual field directions at the same time by placing his eyes at the pupil position 74.

On the other hand, when the image forming optical system and the solid-state image pickup device are used, a plurality of images formed behind the relay lens system 23 are formed on one solid-state image pickup device by the image forming lens. The effect of this configuration can be achieved relatively easily technically regardless of whether the objective optical system or the transmission optical system is an optical system behind it.

In this embodiment, the solid-state image pickup device may be placed at a position corresponding to a plurality of images by increasing the image formation magnification so that images are formed on the plurality of solid-state image pickup devices.

[Supplementary Note 1] In the multi-viewpoint direction endoscope according to claim 2, the pupil separating means is a side on which a light beam is emitted by the transmission optical system and is transmitted by the transmission optical system. It is arranged near a plurality of pupils.

[Supplementary Note 2] In the multi-viewing direction endoscope according to claim 2, a plurality of image pickup means for respectively receiving and picking up a plurality of object images formed by the image forming optical system are provided. There is.

[Supplementary Note 3] In the multi-viewing direction endoscope according to Supplementary Note 2, the pupil separating means is an optical member for separating the light beams contained in the plurality of pupils formed by the transmission optical system into different directions. And a reflecting means for directing a plurality of light fluxes separated by the optical member in a direction substantially parallel to the optical axis of the transmission optical system, and the plurality of image pickup means includes a light flux reflected by the reflecting means. The object images received and formed by the imaging optical system are respectively captured.

[Supplementary Note 4] In the multiple-viewing-direction endoscope according to claim 3, the plurality of light fluxes of the transmission optical system are arranged on the exit side of the light fluxes forming the object image transmitted by the transmission optical system. An optical system for arranging a plurality of light fluxes arranged substantially parallel to the optical axis is arranged, and an imaging lens for receiving only one of the plurality of light fluxes and an object image formed by the imaging lens are imaged. The imaging lens and the imaging means are configured to be integrally moved in a direction intersecting the optical axis of the optical system, and only one of the plurality of light beams is selectively selected. To the imaging lens.

[Supplementary Note 5] In the multiple-viewing-direction endoscope according to claim 3, the plurality of light fluxes of the transmission optical system are arranged on the exit side of the light fluxes forming the object image transmitted by the transmission optical system. An optical system for converting into a plurality of light fluxes arranged substantially parallel to the optical axis and moving in a direction intersecting the optical axis of the optical system in order to selectively transmit only one of the plurality of light fluxes rearward. An optical path switching means that is movably arranged, an image forming optical system that forms an object image by receiving one light beam selected by the optical path switching means, and an object image that is formed by the image forming optical system. And an image pickup means for picking up an image.

[Supplementary Note 6] In the multiple-viewing-direction endoscope according to claim 3, the plurality of light fluxes of the transmission optical system are provided on the exit side of the light fluxes forming the object image transmitted by the transmission optical system. Between the first optical system for converting into a plurality of light fluxes arranged substantially parallel to the optical axis, the second optical system for receiving the plurality of light fluxes to form an image, and between the first optical system and the second optical system And a light beam switching unit that selectively transmits only one of the plurality of light beams, and an image pickup unit that receives and picks up an object image formed by the second optical system.

[Supplementary Note 7] In the multiple-viewing-direction endoscope according to Supplementary Note 4 or Supplementary Note 5, a plurality of corresponding ones of the plurality of light beams from the plurality of different directions are provided in either the objective optical system or the transmission optical system. It is equipped with a means for setting the pupil.

[Supplementary Note 8] In the multi-viewing direction endoscope according to claim 3 or claim 4, the endoscope has a common optical axis with the transfer optical system and corresponds to each view direction from the transfer optical system. It has an imaging optical system for forming an object image formed by the light fluxes included in the range of a plurality of pupils.

[Supplementary Note 9] In the multi-view direction endoscope according to Supplementary Note 8, there is provided one image pickup means for receiving and picking up a plurality of object images formed by the image forming optical system. .

[Supplementary Note 10] In the multiple-viewing-direction endoscope according to Supplementary Note 8, the image-forming optical system is an eyepiece optical system for forming a plurality of object images corresponding to different visual-field directions so as to be visually observable. thing. The endoscope described in appendix 10 is also excellent in resistance to high temperature due to sterilization.

[Supplementary Note 11] In the multi-viewpoint direction endoscope according to Supplementary Note 8, a plurality of pupils corresponding to the light beams from the plurality of different directions are provided in either the objective optical system or the transmission optical system. Is provided.

[Supplementary Note 12] In the multiple-viewing-direction endoscope according to Supplementary Note 10, one of the objective optical system, the transmission optical system, and the eyepiece optical system is provided with a plurality of light beams from different directions. A means for setting a plurality of corresponding pupils is provided.

[Appendix 13] In the endoscope according to claim 6 or 7, an optical axis common to the transmission optical system is provided on the exit side of the light flux forming the object image transmitted by the transmission optical system. It has an eyepiece optical system. The endoscope described in appendix 13 is also excellent in resistance to high temperature due to sterilization.

[Supplementary Note 14] In the multiple-viewing-direction endoscope according to claim 6 or 7, the plurality of light beams are transmitted to the exit side of the light beams forming the object image transmitted by the transmission optical system. An optical system for converting into a plurality of light fluxes arranged substantially parallel to the optical axis of the optical system, a reflecting means for directing the plurality of light fluxes emitted from the optical system in different directions, and respective light fluxes reflected by the reflecting means. A plurality of image forming optical systems provided in the respective optical paths of the respective light fluxes for forming an object image, and a plurality of image capturing means for receiving and capturing the respective object images formed by the image forming optical system. And are equipped with. The endoscope described in appendix 14 is also excellent in resistance to high temperature due to sterilization.

[Supplementary Note 15] In the multiple-viewing-direction endoscope according to claim 6 or 7, the plurality of light beams are transmitted from the transmission optical system to the exit side of the image position formed by the transmission optical system. An optical system for arranging a plurality of light fluxes arranged substantially parallel to the axis is arranged, and an imaging lens for receiving only one of the plurality of light fluxes from the optical system and an object image formed by the imaging lens. An image pickup means for receiving and picking up an image, and the imaging lens and the image pickup means are configured to be integrally moved in a direction intersecting the optical axis of the optical system, and only one of the plurality of light fluxes is provided. Is selectively made incident on the imaging lens.

[Supplementary Note 16] In the multi-viewing direction endoscope according to claim 6 or 7, the plurality of light beams are transmitted to the exit side of the image position formed by the transfer optical system. An optical system for converting into a plurality of light fluxes arranged substantially parallel to the axis, and moving in a direction intersecting the optical axis of the optical system in order to transfer only one of the plurality of light fluxes from the optical system to the rear side. Optical path switching means that is arranged possible,
An image forming optical system which receives the light flux selected by the optical path switching means and forms an object image in the rear.

[Supplementary Note 17] In the multiple-viewing-direction endoscope according to claim 8, there is provided a transmission blocking switching means for selectively setting one of the plurality of pupils from the objective optical system into a transmission state. .

[Supplementary Note 18] A multi-viewing direction endoscope having an objective optical system having a plurality of viewing directions and an image pickup means for receiving and picking up an object image formed by the objective optical system, The objective optical system includes a prism optical system that receives light fluxes from a plurality of mutually different directions and converts the light fluxes into a plurality of light fluxes that are arranged substantially in parallel, a means that sets a plurality of pupils corresponding to the respective light fluxes, and A front optical system including a transmission blocking switching unit that selectively sets one of the pupils of the unit to a transmissive state, and a rear optical system having a single optical axis and a converging property. The object image corresponding to the pupil selected by the transmission blocking switching unit and formed by the rear optical system is captured.

[Supplementary Note 19] In the multiple-viewing-direction endoscope according to Supplementary Note 18, the image pickup means is a solid-state image pickup element.

[0095]

As described above, according to the multiple-viewing-direction endoscope of the present invention, there is no movable portion at the distal end portion and the image transmitting portion of the endoscope, and the structure of the distal end portion is simple and the assembling is easy. Good, there is an effect that an image without deterioration in the peripheral portion can be obtained.

According to the second aspect of the invention, there is an effect that the distal end portion of the endoscope and the image transmitting portion have no movable portion, and the sterilization resistance is excellent.

According to the first to seventh aspects of the invention, a plurality of object images corresponding to a plurality of visual field directions can be simultaneously observed or selectively observed. There is an effect that it is possible to simultaneously provide a plurality of object images corresponding to the visual field directions of the above without overlapping.

[Brief description of drawings]

1 to 3 relate to a first embodiment, and FIG.
FIG. 1A is a configuration diagram of a multi-viewing direction endoscope, and FIG. 1B is a diagram showing a configuration example of an aperture stop.

FIG. 2 is an overall configuration diagram of an endoscope device.

FIG. 3 is a configuration diagram of an objective optical system using pupil division.

4 to 9 relate to a second embodiment, and FIG.
FIG. 4A is a configuration diagram of a multi-viewing direction endoscope including an objective optical system that uses a decentered optical system, and FIG. 4B is a configuration diagram of an endoscope according to a modification of the second embodiment.

FIG. 5 is a configuration diagram of an objective optical system that uses a decentered optical system and has a common afocal portion.

FIG. 6 is a configuration diagram of an objective optical system that uses a decentered optical system and achieves a perspective view by refraction.

FIG. 7 is a configuration diagram according to a design example of an objective optical system using a decentered optical system.

FIG. 8 is a configuration diagram according to a design example in which an objective optical system and a relay lens system are combined.

FIG. 9 is a front view of an objective optical system having three viewing directions.

10 to 13 relate to the third embodiment, and FIG. 10 is a configuration diagram of a multi-viewing direction endoscope having a pupil switching device.

11A and 11B are configuration diagrams of a multiple-viewing-direction endoscope in which the viewing direction can be switched by an image rotator.

FIG. 12 is a configuration diagram of a multi-view direction endoscope in which the view directions can be switched by moving a solid-state image sensor or the like.

FIG. 13A is a configuration diagram of a multiple-viewing-direction endoscope in which a pupil switching device is provided near a pupil of an objective optical system, FIG.
3B is a configuration diagram of a multi-viewing direction endoscope different from FIG.

14A is a configuration diagram of a multiple-viewing-direction endoscope according to a fourth embodiment, and FIG. 14B is a configuration diagram of an endoscope in which an objective optical system is partially shared. .

FIG. 15 is a configuration diagram of a variable field-of-view endoscope according to a conventional example.

FIG. 16 is a configuration diagram of a field-of-view variable endoscope according to a conventional example.

FIG. 17 is a configuration diagram of an arthroscope according to a conventional example.

[Explanation of symbols]

 11 ... Endoscope 21 ... Brightness diaphragm 22 ... Objective optical system 23 ... Relay lens system 24 ... Eyepiece optical system 29a ... Front optical system 25, 26 ... Objective lens 27 ... First prism 28 ... Second prism 29b ... Rear optical system System I1, I2 ... Objective image P2 ... Pupil

Claims (9)

[Claims] 1. An objective optical system having a plurality of visual field directions and a plurality of pupils corresponding to the visual field directions and arranged so as not to overlap each other, and forming one or more object images. A transfer optical system formed to have a size equal to or larger than a size of a plurality of pupils from the objective optical system and transmitting the object image from the objective optical system and the plurality of pupils to the rear. A multi-view direction endoscope that is characterized in that 2. The multi-viewing direction endoscope according to claim 1, wherein a plurality of pupils respectively corresponding to the light beams from the plurality of different directions, the plurality of pupils formed by the transmission optical system, Characterized in that it has a pupil separating means for separating each, and an image forming optical system for forming an object image formed by a light beam included in a range of the separated pupils corresponding to respective visual field directions. Multi-view directional endoscope. 3. An objective optical system having a plurality of visual field directions and a plurality of pupils corresponding to these visual field directions and formed so as not to overlap with each other to form an object image, and a single optical axis. And a multi-viewing direction endoscope including a transfer optical system for transmitting an object image from the objective optical system and a plurality of pupils, wherein the objective optical system allows light beams from different directions to enter. A front optical system that emits the light beams as a plurality of substantially afocal light beams that are arranged in parallel in parallel along the optical axis of the transmission optical system, and a single optical axis common to the transmission optical system. And a rear optical system that converges the plurality of light beams from the front optical system to form an object image in the rear, and the transfer optical system includes a plurality of light beams corresponding to the plurality of light beams from the rear optical system. The size is equal to or larger than the size of the pupil, and Transmitting the object image and a plurality of pupils from rectangular optical system in the rear, a plurality of sight endoscope characterized by. 4. An objective optical system having a plurality of visual field directions and a plurality of pupils corresponding to these visual field directions and formed so as not to overlap with each other to form a plurality of object images, and a single optical axis. And a transmission optical system having a plurality of visual field directions, wherein the objective optical system makes light beams incident from different visual field directions incident on the optical axis of the transmission optical system. And a front optical system that emits a plurality of substantially afocal light fluxes that are arranged substantially in parallel and that receives a plurality of emitted lights from the front optical system to converge a plurality of object images and a plurality of objective images behind. It comprises a plurality of rear optical systems arranged in parallel to form each, and the transfer optical system has a size equal to or larger than a size of a plurality of pupils corresponding to a plurality of light beams from the rear optical system. A plurality of rear optical systems Transmitting the plurality of object images and a plurality of pupils of al backwards, multiple viewing directions endoscope, characterized in that. 5. A multi-viewing direction internal view including an objective optical system having a plurality of viewing directions and a plurality of pupils corresponding to the plurality of viewing directions, and a transfer optical system having a single optical axis. A mirror, wherein the objective optical system changes the optical paths of at least one of the plurality of pupils into which a plurality of light beams from different directions are respectively incident, and directs the respective light beams in substantially the same direction. A front optical system including a prism optical system for converting into a light flux,
A rear optical system that forms an object image composed of a plurality of light beams from the front optical system at substantially the same position, and the transfer optical system rearranges the object image from the rear optical system and the plurality of pupils to the rear. A multi-view direction endoscope that is characterized in that it is transmitted to. 6. A multi-viewing direction internal endoscope including an objective optical system having a plurality of viewing directions and a plurality of pupils corresponding to the plurality of viewing directions, and a transfer optical system having a single optical axis. The objective optical system is a mirror, and the objective optical system receives a plurality of lenses having optical axes in mutually different directions, receives each light beam transmitted through the plurality of lenses, and substantially parallels the light beams along an optical axis of the transmission optical system. A front optical system including a prism optical system for converting into a plurality of light fluxes arranged in parallel with each other, and a size including the light flux emitted from the front optical system, and simultaneously forming a plurality of light fluxes on an image plane. Therefore, a rear optical system having a single optical axis and a convergent property with respect to the emitted light beam, and the transmission optical system transmits the object image from the rear optical system and a plurality of pupils rearward. The characteristic multi-view direction endoscope. 7. A multi-viewing direction internal view including an objective optical system having a plurality of viewing directions and a plurality of pupils corresponding to the plurality of viewing directions, and a transfer optical system having a single optical axis. The objective optical system is a mirror, and the objective optical system divides the pupil into a plurality of pupils, a prism member that makes incident directions of light beams corresponding to the divided pupils different from each other, and optical axes in different directions. A front optical system including a plurality of lenses having, and a rear optical system having a single optical axis for simultaneously forming a plurality of light beams on an image plane and having a convergent property with respect to an emitted light beam, A multiple-viewing-direction endoscope, wherein the transfer optical system transfers the object image and the plurality of pupils from the rear optical system rearward. 8. A multiple-viewing-direction type including an objective optical system including a plurality of viewing directions, a plurality of pupils corresponding to these viewing directions, and an optical system for forming an image at the same position by a light beam from each pupil. Endoscope. 9. A multi-view direction endoscope including a front optical system including a lens having a negative refractive power and an objective optical system including a rear optical system having a converging property including a lens having a positive refractive power. The front optical system includes a plurality of lenses having optical axes in mutually different directions, and light fluxes from different directions, and the lenses are arranged substantially parallel to each other along the optical axis of a transmission optical system that delivers the light fluxes. A rear optical system having a size and a single optical axis including the light beam emitted from the front optical system, and a plurality of light beams to convert the object to the image plane at the same time. A multi-view directional endoscope characterized in that it forms an image.