JPH0921962A - Stereoscopic endoscope - Google Patents

Abstract

(57) [Summary] [Object] An object of the present invention is to provide a stereoscopic endoscope capable of changing the stereoscopic effect and enabling stereoscopic viewing from different angles without moving the primary optical system. A structure is characterized in that three or more secondary optical systems that take in light fluxes that have passed through different regions in a pupil Ep of the primary optical system 10 are provided. Each secondary optical system includes separator lenses 37a to 37e arranged in the pupil of the primary optical system, and image pickup elements 38a to 38e arranged at positions conjugate with the image formation positions of the separator lenses.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stereoscopic endoscope for stereoscopically observing an object in a space that cannot be directly observed from the outside.

[0002]

2. Description of the Related Art A stereoscopic endoscope is disclosed in, for example, Japanese Patent Laid-Open No. 6-19.
As disclosed in Japanese Patent No. 4581, a rigid mirror provided with a primary optical system including an objective lens system that forms an object image and a relay system that transmits this image, and an image transmitted by this primary optical system It is provided with a pupil splitting unit that splits the image into right and left portions so that the image can be viewed, and two secondary optical systems that respectively observe or image the two divided images.

This type of stereoscopic rigid endoscope is used for medical purposes for observing a site inside a body cavity, or for industrial purposes for observing the inside of a machine such as an engine.

The images photographed by the respective secondary optical systems use, for example, a method using polarized glasses, a method of displaying left and right screens in a time division manner in synchronization with glasses with a liquid crystal shutter, and a lenticular screen. 2 from the back
It is displayed by a method of projecting with one projector, and the observer can recognize the displayed image as a stereoscopic image.

[0005]

However, since the stereoscopic rigid endoscope described in the above-mentioned publication is provided with two secondary optical systems in a fixed manner, the stereoscopic rigid endoscope is not suitable for stereoscopic viewing.
The positions of the two viewpoints are fixed, and the observation direction with respect to the object cannot be changed unless the entire rigid endoscope is displaced with respect to the object.

Generally, if an object can be observed from a plurality of different directions, it is possible to more accurately determine the shape of the object, but the observation target of the endoscope is usually in a narrow space. , It is difficult to change the viewpoint by moving the entire rigid endoscope.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and provides a stereoscopic endoscope capable of changing the stereoscopic viewpoint of an object without moving the primary optical system. The purpose is to provide.

[0008]

In order to achieve the above-mentioned object, the stereoscopic endoscope according to the present invention has three secondary optical systems for taking in light fluxes passing through different regions in the pupil of the primary optical system. It is characterized by being provided above. Each secondary optics
It is provided with a separator lens arranged in the pupil of the primary optical system and an image pickup element arranged at a position conjugate with an image forming position of the separator lens.

By selecting any two of the images input through the three separator lenses, stereoscopic vision becomes possible, and by changing the combination of the secondary optical systems to be selected, a stereoscopic image with respect to the object is obtained. The prospective direction of vision can be changed. With this configuration, the object can be observed from a plurality of different directions without moving the primary optical system, and the property of the object can be determined more accurately.

It should be noted that, in this specification, the 2
The change of the position of at least one of the two viewpoints is defined as “change of the prospective direction of stereoscopic vision”. This includes not only the change in the direction of the line segment connecting the two viewpoints, but also the change by moving the viewpoint without changing the direction of the line segment. The latter includes a case where two viewpoints are moved while keeping the viewpoint interval constant, and a case where at least one of the two viewpoints is moved while changing the viewpoint interval to change the stereoscopic effect.

In order to change the directionality of the line segment connecting the two viewpoints, it is necessary to arrange the separator lens two-dimensionally within the pupil of the primary optical system. When it is not necessary to change the directionality of the line segment, the separator lens may be arranged in a straight line in the pupil.

When the captured image is displayed by the projection device using the lenticular screen, the observer changes the viewpoint on the screen by projecting the image captured by each secondary optical system by the projector. The observation angle with respect to the object can be changed by. It should be noted that when an image is taken by the image pickup device, not only is it displayed in real time, but it can also be recorded and saved on a video tape or the like.

The number of secondary optical systems need only be three or more, and five separator lenses may be arranged in a straight line, or the same number or more separator lenses may be arranged two-dimensionally. Good. When four or more secondary optical systems are provided, at least one of them may be used for observation with the naked eye. For example, when five secondary optical systems are provided, three secondary optical systems may be used. One for photographing and two for observation with the naked eye, and two for observation can be shared with photographing.

The primary optical system is provided at an insertion portion to be inserted into a space such as a body cavity and has an objective lens system located at the tip of the insertion portion and at least one relay lens system.
The image transmitted by the first relay lens system is transmitted to the observation unit connected to the base end side of the insertion unit by the relay lens system in the subsequent stage. In this case, the separator lens and the image sensor of the secondary optical system are arranged in the observation section.

In another example, the relay lens system is arranged only on the tip side of the insertion portion, and the separator lens of the secondary optical system is arranged in accordance with the pupil located inside the insertion portion of the relay lens system. The image formed by the separator lens is transmitted to the observation unit by the image guide fiber bundle and is photographed by the image pickup device in the observation unit, or is photographed by the image pickup device arranged at the primary image forming position of the separator lens and is an electric signal. Is transmitted to the observation section through the signal line.

Further, when a primary optical system and a secondary optical system are separately provided on the insertion portion side and the observation portion side, a monocular rigid endoscope is used as the insertion portion and stereoscopic vision is used as the observation portion. It is also possible to have a configuration in which a power adapter is connected. In this case, adjustment means may be provided for changing the relative positional relationship between the primary optical system and the secondary optical system in order to align them. The adjusting action may be provided in the connecting unit that connects the positions of the insertion unit and the observation unit, or may be provided in the holding unit that integrally holds the separator lens and the image pickup device.

[0017]

Embodiments of the stereoscopic endoscope according to the present invention will be described below. As shown in FIG. 1 (A), the stereoscopic endoscope according to the first embodiment is connected to a rigid insertion portion 1 to be inserted into a narrow space such as a body cavity and a proximal end side of the insertion portion 1. The observation unit 2 is provided.

Inside the insertion section 1, an objective lens system 11 for forming an image of an object, which is composed of four elements in three groups, and the objective lens system 11 are provided.
A plurality of relay lens systems 12 and 12 composed of a plurality of lenses for transmitting the image formed by the primary optical system 1.
A pupil forming lens system 13 forming an exit pupil of 0 is arranged in order from the object side, and the primary optical system 1 is formed by these lens systems.
0 is configured.

In the observation section 2, the pupil Ep of the primary optical system 10 is
A light receiving unit 30 including five secondary optical systems is provided in accordance with the above. The light receiving unit 30 is shown in FIG.
(B) As shown in (C), five separator lenses 37a arranged in parallel on the diameter of the pupil Ep,
37b, 37c, 37d, 37e and an image pickup device 38 for picking up an image formed by these separator lenses
a, 38b, 38c, 38d, and 38e, each separator lens and the image pickup element form a pair to form one secondary optical system.

As shown in FIG. 1A, the light receiving unit 30 is adjusted by the adjusting means 40 in the front-back direction along the optical axis Ax1, and in the left-right direction perpendicular to the optical axis (in the plane of FIG. 1).
It is possible to move integrally along.

The adjusting means 40 is provided on a holding frame 41 for supporting the light receiving unit 30 from both the left and right sides, and at an end of the holding frame 41 opposite to the light receiving unit 30, and the both sides are rotatably supported by the holding frame 41. The left and right position adjusting screw 44 is attached to the supported left and right position adjusting screw 44 and the mounting part 2a of the observation part 2 so as to be movable back and forth in the optical axis Ax1 direction.
And a front and rear position adjusting bolt 45 for holding

A nut portion 45a which is screwed to the left and right position adjusting screw 44 is fixed to the tip of the front and rear position adjusting bolt 45, and a front and rear screw which is screwed to the front and rear position adjusting bolt 45 is provided inside the wall surface of the mounting portion 2a. A position adjusting knob 46 is rotatably attached.

With this configuration, the left and right position of the light receiving unit 30 can be entirely adjusted by rotationally adjusting the left and right position adjusting knob 44a fixed to the left and right position adjusting screw 44, and By adjusting the front-rear position adjusting knob 46, the position of the light receiving unit 30 in the front-rear direction can be adjusted as a whole.

By adjusting these two-dimensional directions, the object-side surfaces of the separator lenses 37 to 37e are accurately positioned within the pupil Ep of the primary optical system 10 and the optical axis Ax1 of the primary optical system 10 is adjusted. Positioned symmetrically.

Images obtained by viewing the object from different angles according to the positions occupied by the respective separator lenses in the pupil Ep are captured in the respective image pickup devices. That is, images having parallax with each other are captured in each of the five secondary optical systems, and by displaying any two of these images by a known stereoscopic image display method, the observer stereoscopically displays the object. Can be observed.

Further, by changing the selected secondary optical system, it is possible to change the prospective direction of stereoscopic vision with respect to the object. For example, when the displayed stereoscopic image is switched from the image captured through the separator lenses 37a and 37e at both ends to the image captured through the inner separator lenses 37b and 37d, the parallax becomes small. The three-dimensional effect becomes smaller. In addition, from the images taken through the adjacent separator lenses 37a and 37b on one side, the adjacent separator lenses 37d and 37e on the other end side are formed.
When switching to the image taken via, the stereoscopic effect does not change, but the observation direction for the object changes,
The observation direction with respect to the object can be changed without mechanical movement.

Further, when an image is displayed by the projection device 200 using a lenticular screen, as shown in FIG. 2, five images captured by each secondary optical system are provided in parallel in the horizontal direction. 5 projectors 2
It is possible to simultaneously project from 10 to 214 toward the back surface of the lenticular screen 220.

The lenticular screen 220 is formed by assembling a large number of cylindrical lenses having a generatrix in a direction perpendicular to the plane of the paper, and the direction of the image projected from each projector through the lenticular screen 220 is determined by the respective cylindrical lenses. It is limited to a predetermined direction according to the angle of incidence on the lens. Therefore, when the observer's viewpoint changes in the horizontal direction, the photographer observes images from different projectors accordingly, and by changing the viewpoint, the observation direction for the object can be changed.

For example, when the head H of the photographer is at the position shown by the solid line, the image of the second projector 211 mainly enters the right eye and the image of the third projector 212 mainly enters the left eye. On the other hand, when the head H of the photographer moves horizontally to the position indicated by the broken line, the image of the fourth projector 213 is incident on the right eye and the image of the fifth projector 214 is incident on the left eye. To do.

The stereoscopic endoscope according to the second embodiment shown in FIG. 3 constitutes an endoscope for monocular viewing only by the insertion portion 1 provided with the primary optical system 10, and the endoscope for the stereoscopic vision is shown in FIG. The observation unit 2 provided with a secondary optical system is attached as a binocular vision adapter. The optical configuration and the configuration of the adjusting means 40 are the same as those of the first embodiment shown in FIG.

A collar-shaped hood 14 is attached to the base end side of the insertion portion 1 to come into contact with the periphery of the observer's eyes when observing with a single eye to block ambient light. The observation part 2 is fixed to the insertion part 1 via an attachment 50 attached to the hood 14.

The attachment 50 includes a mounting ring 51 that is attached to the hood 14 from the observation section 2 side to enclose the hood 14 from the outside, and a mounting piece 52 that is in contact with the hood 14 from the object side and is attached to the mounting ring 51. , A fixing bolt 5 for fixing the contact piece 52 to the mounting ring 51
And 3.

The mounting ring 51 has a disc portion 51a which is in contact with the hood 14 and has an opening formed in the center thereof, and the disc portion 5a.
A cylindrical portion 51b that rises from the peripheral portion of 1a toward the object side and surrounds the outer periphery of the hood 14, and a flange portion 51c that is formed from the object-side tip of this cylindrical portion toward the inner periphery are integrally configured. ing. The contact piece 52 is a small piece having an L-shaped cross section, and is located at least at three circumferential positions.
4 is attached to the mounting ring 51.

Further, adjustment bolts 54 projecting toward the observation section 2 side are fixed at three locations in the circumferential direction on the outer peripheral portion of the surface of the attachment ring 51 on the observation section 2 side. In the observation section 2,
An outer flange 2b is formed in the peripheral portion on the insertion portion 1 side, and a through hole 2c into which the adjustment bolt 54 is inserted is formed in the outer flange 2b. Adjustment bolt 54
The nuts 55 and 56 located on both sides of the outer flange 2b while being inserted into the through hole 2c.
The insertion part 1 fixed to b and fixed to the attachment 50 is fixed to the observation part 2.

In this embodiment, by adjusting the positions of the nuts 55 and 56 screwed into the three adjusting bolts 54, the positional relationship between the attachment 50 and the observation section 2 is three-dimensionally adjusted. can do.

4 to 7 show Embodiments 3 to 6 of the present invention. In these examples, the relay lens system 12 and the pupil forming lens system 13 are arranged only on the distal end side of the insertion section 1, and the separator lens of the secondary optical system is matched with the pupil of the primary optical system located in the insertion section 1. 37a to 37e are arranged. Therefore, the distal end portion 1a of the insertion portion 1 in which the lenses 11 to 13 are arranged is hard as in the first embodiment, but the intermediate portion 1b connecting the distal end portion 1a and the observation portion 2 has a flexible tube. Can also be used.

In the third embodiment shown in FIG. 4, the image pickup device is arranged at the primary image forming position of the separator lens to constitute the light receiving unit 30 similar to that of FIG. 1, and the image signal from each image pickup device is an electric signal. Signal line 30a as an intermediate portion 1
It is transmitted to the observation unit 2 through b.

In the fourth embodiment shown in FIG. 5, the image guide fiber bundles 39a to 39e are arranged so that the incident end faces are aligned with the primary image forming positions of the separator lenses 37a to 37e, and the image transmitted to the observing section 2 by this. Is imaged on the image pickup devices 38a to 38e fixed in the observation unit 2 via the imaging lenses 32a to 32e.

In the fifth embodiment shown in FIG. 6, the image captured by the separator lens is transmitted to the observing section 2 side by using the image guide fiber bundles 39a to 39e in substantially the same manner as in the fourth embodiment. However, in this example, the secondary optical system includes two eyepiece optical systems that allow observation with the naked eye, in addition to the three including the image pickup devices 38a to 38c. That is, the image guide fiber bundles 39a, 39c,
The image transmitted by 39e is formed by the imaging lenses 32a, 3a.
2b and 32c provide image pickup devices 38a and 38b,
38c is imaged. On the other hand, the image transmitted by the image guide fiber bundles 39b and 39d is transmitted to the outside of the observation unit 2 through the eyepieces 33a and 33b,
It enables observation with the naked eye.

FIG. 7A and a partially enlarged view of FIG.
In the sixth embodiment shown in (B), while adopting the same configuration as the fifth embodiment, an image used for observation with the naked eye is also used for photographing. Image guide fiber bundle 39a, 3
The configurations of the three central secondary optical systems that directly form the images from 9c and 39e are the same as in the fifth embodiment.

Image guide fiber bundles 39b, 39
A part of the light flux transmitted by d and transmitted through the imaging lenses 32d and 32e is a half mirror 6 as an optical path splitting means.
0a, 60b and re-imaging lenses 32f, 3
An image is formed on the image pickup devices 38d and 38e via 2g. The light flux transmitted through the half mirrors 60a and 60b is used for observation with the naked eye through the eyepiece lenses 33a and 33b.

In each of the above embodiments, five secondary optical systems are provided, and five separator lenses are provided in parallel on the diameter of the pupil of the primary optical system. However, the number of secondary optical systems is different. May be three as in the seventh embodiment shown in FIG.

In the example of FIG. 8, the primary optical system 10 is arranged in the rigid insertion part 1 as in the first embodiment, and the three separator lenses 37a, 37b, 37c are formed in the observation part 2 at the respective imaging positions. Arranged image pickup elements 38a, 38b, 38
A secondary optical system composed of c and c is provided.

In this example, the central separator lens 37
c and the image sensor 38c are integrally fixed to the observation unit 2, and the separator lenses 37a and 37b on both sides are fixed.
The image pickup elements 38a and 38b are integrally supported by support members 47a and 47b so as to be movable.

The base end portions of the support members 47a and 47b are screwed into a space adjusting screw 42 which is rotatably supported on the tip side which is the primary optical system 10 side of the holding frame 41. In the center of the space adjustment knob 43
Are fixed integrally. The mounting structure of the holding frame 41 to the mounting portion 2a is the same as that of the first embodiment, and thus the description thereof is omitted.

The interval adjusting screw 42 is formed with screw grooves whose spiral directions are opposite to each other with the interval adjusting knob 43 as a boundary, and by rotating and adjusting the interval adjusting knob 43, the supporting members 47a, 47b are formed. Move, and as a result, the separator lenses 37a and 37b and the image pickup device 38a,
38b move away from each other so as to be symmetrical with respect to the optical axis Ax1 of the primary optical system 10, or move so as to approach each other.

According to the configuration of the seventh embodiment, as shown in FIGS. 9A and 9B, it is possible to change the interval between the separator lenses 37a and 37b on both sides of the central separator lens 37c. It is possible to continuously change the stereoscopic effect of the observation visual field.

When the number of secondary optical systems is three, FIG.
If the separator lenses 37a to 37c are arranged so as to be arranged in the pupil Ep without a gap as shown in (C), the separator lenses cannot be moved, but the maximum amount of light taken into each secondary optical system is secured. can do.

From the viewpoint of changing the observation direction,
The three separator lenses provided in the observation part are shown in FIG.
As shown in FIG. 3, the three secondary lenses are arranged so as to be circumscribed with each other, and the three separator lenses and the image pickup devices provided corresponding to the three separator lenses are integrally movable to thereby make the relative relationship between the three secondary optical systems. It is also possible to change the range of the light flux taken in by each secondary optical system within the pupil Ep without changing the.

Further, the separator lenses are not only arranged in a straight line as shown in FIGS. 1 (C) and 9 above, but also three or more separator lenses are arranged as shown in FIG. The lenses may be arranged two-dimensionally. In the sequences of FIG. 1 (C) and FIG. 9, the selected 2
It is possible to change the prospective direction of stereoscopic vision for the object of the two secondary optical systems only in one direction which is the arrangement direction of the separator lenses.

Therefore, if this is the horizontal direction, it is necessary to rotate the entire endoscope in order to obtain a stereoscopic image observed from another direction, for example, the vertical direction. There is a time difference in the timing at which the image is obtained. The internal organs of the endoscope or the internal mechanism of the machine are often accompanied by movements, and it is not preferable that there is a time lag in switching images.

When the separator lenses are arranged two-dimensionally as shown in FIG. 10, the directionality of the line segment connecting the two viewpoints can be changed only by changing the selection of the secondary optical system.

For example, in the example of FIG. 10A, by changing the combination of the separator lenses (secondary optical system) to be selected, the directionality of the line segments connecting the viewpoints is different from each other by 60 ° of d1, d2 and d3. You can change the direction. Also,
According to the arrangement of FIG. 10B, the directionality of the line segment connecting the two viewpoints can be switched between the horizontal direction dh and the vertical direction dv by selecting the separator lens.

FIGS. 10C and 10D show an example in which more separator lenses are arranged in the pupil Ep of the primary optical system. According to these examples, the degree of freedom in selection becomes higher, and the prospective direction of stereoscopic vision for the object can be changed without moving the primary optical system.

[0055]

As described above, according to the present invention, by providing three or more secondary optical systems each including a separator lens and an image pickup element, an image input through at least three separator lenses can be displayed. By selecting any two, stereoscopic vision becomes possible, and by changing the combination of the secondary optical systems to be selected, the prospective direction of stereoscopic vision with respect to the object is changed, and the object is selected from a plurality of directions. It can be observed in detail.

[Brief description of drawings]

FIG. 1 shows Embodiment 1 of the stereoscopic endoscope of the present invention,
(A) is an overall sectional view, (B) is an enlarged view of the light receiving unit,
(C) is a plan view showing the arrangement of the separator lenses on the pupil.

FIG. 2 is an explanatory diagram showing the principle of a stereoscopic image display device using a lenticular screen.

FIG. 3 is an enlarged view of an observation unit showing a stereoscopic endoscope according to a second embodiment.

FIG. 4 is an overall sectional view showing a stereoscopic endoscope according to a third embodiment.

FIG. 5 is an overall sectional view showing a stereoscopic endoscope according to a fourth embodiment.

FIG. 6 is an overall sectional view showing a stereoscopic endoscope according to a fifth embodiment.

FIG. 7 is an overall sectional view showing a stereoscopic endoscope according to a sixth embodiment.

FIG. 8 is an overall sectional view showing a stereoscopic endoscope according to a seventh embodiment.

FIG. 9 is a plan view showing a modified example of the arrangement of the separator lenses on the pupil.

FIG. 10 is a plan view showing another modified example of the arrangement of the separator lenses on the pupil.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Insertion part 2 Observation part 10 Primary optical system 11 Objective lens system 12 Relay lens system 13 Pupil formation lens system 14 Hood 200 Projector 210-214 Projector 220 Lenticular screen 30 Light receiving unit 30a Signal line 32a-32e Imaging lens 32f, 32g Re-imaging lens 33a, 33b Eyepiece lens 37a-37e Separator lens 38a-38e Imaging device 39a-39e Image guide fiber bundle 40 Adjusting means 50 Attachment 51 Attachment ring 52 Abutting piece 53 Fixing bolt 54 Adjustment bolt 55, 56 Nut 60a, 60b half mirror

Claims (10)

[Claims] 1. A stereoscopic endoscope having a primary optical system having an objective lens system and a relay lens system, and a plurality of secondary optical systems for taking in light fluxes passing through different regions in a pupil of the primary optical system. The secondary optical system includes a separator lens arranged in the pupil of the primary optical system, and an image pickup element arranged at a position conjugate with an image forming position of the separator lens. At least three or more are provided, The stereoscopic endoscope characterized by the above-mentioned. 2. The stereoscopic endoscope according to claim 1, wherein the image pickup device is arranged at a primary image forming position of the separator lens. 3. Each of the secondary optical systems has an image guide fiber bundle provided with an incident end face at a primary image forming position of the separator lens, and the image pickup device includes the image guide fiber bundle. The stereoscopic endoscope according to claim 1, wherein the stereoscopic endoscope is arranged at a secondary image forming position for receiving an image transmitted by. 4. The separator lens is configured so that the primary direction of the separator lens can be changed in one direction within a visual field by selecting any two of the secondary optical systems so as to change the prospective direction of stereoscopic vision for an object to be observed. The stereoscopic endoscope according to claim 1, wherein the stereoscopic endoscopes are arranged side by side in a straight line in a pupil of the optical system. 5. The separator lens is configured such that by selecting any two of the secondary optical systems, the primary direction of the primary lens can be changed in a plurality of directions within the field of view of a stereoscopic view of an object to be observed. The stereoscopic endoscope according to claim 1, wherein the stereoscopic endoscope is arranged two-dimensionally in the pupil of the optical system. 6. The stereoscopic endoscope according to claim 5, wherein at least three separator lenses are arranged so that their centers coincide with the vertices of a triangle. 7. The separator lens is relatively separated,
The stereoscopic endoscope according to claim 4, wherein the stereoscopic endoscope is movable in an approaching direction. 8. The secondary optical system observes at least three image pickup devices, two separator lenses arranged at a pupil position of the primary optical system, and an image captured by the separator lenses. The stereoscopic endoscope according to claim 1, further comprising: two eyepiece optical systems each including an eyepiece lens system that operates. 9. The eyepiece optical system comprises an optical path splitting means between the separator lens and the eyepiece lens system, and an image pickup element for receiving one light flux split by the optical path splitting means. The stereoscopic endoscope according to claim 8. 10. The display device for a stereoscopic endoscope according to claim 1, wherein a plurality of lenticular screens and a plurality of image signals from the plurality of image pickup devices are respectively projected toward the lenticular screen. A display device comprising: a projector.