JPS60241018A - Stereoscopic endoscope - Google Patents

Abstract

PURPOSE:To make an in-cavity insert part thin by providing a couple of ocular systems through which images are observed respectively when one objective lens fixed to a rotating member supported pivotally on the tip part of the endoscope so that its optical axis is not aligned to the optical axis of the rotating member takes two different positions. CONSTITUTION:The rotary member 13 is rotated by a motor 12 and then the objective lens 15 takes positions which are 180 deg. symmetrical about the rotating shaft 12a alternately. Images when the lens takes those different positions, i.e. two images A and B having parallax are received by a solid-state image pickup device 16 and converted into a signal, which is passed through a signal processing circuit, so that the images are displayed on a couple of image receiving tubes. Those images A and B are viewed with the right and left eye stereoscopically.

Description

[Detailed description of the invention] Technical field The present invention relates to a stereoscopic endoscope.

Prior Art To realize stereoscopic vision, it is generally necessary to obtain images with parallax using a pair of objective systems, and to observe these images using a pair of eyepiece systems.

Therefore, in the conventional stereoscopic endoscope, as shown in FIG. 1, for example, the objective lens 1. Image guide 2.
An observation system consisting of 3 eyepieces is installed inside a pair of endoscopes,
The parallax created by both objective lenses 1.1 was used to provide stereoscopic viewing. However, in this configuration, objective lens 1
．． Image guide 2. Since two eyepiece lenses 3 are required, the overall structure is complicated, and in particular, since there are two objective lenses 1° and two image guides 2, the endoscope's insertion portion into the body cavity tends to be thick, which is undesirable. The problem was that it was not sharp.

Therefore, if we consider a configuration in which two image guides are combined into one in order to make the insertion portion into the body cavity thinner, the result will be as shown in FIG. 2. That is, although the front groups 4a, 4a of the pair of objective systems 4, 4 are separate, by using the prism 5 and the half mirror 6, the rear group 4b is shared, and the images from both objective systems 4, 4 can be used as image guides. 2, and a shutter 7 is provided at the rear of each front group 4a, 4a.
゜7 are placed respectively and opened and closed alternately at high speed (to the extent that an afterimage of the eye remains), so that images with parallax are transferred to the image guide 2.
so that it appears on the output end face of the Then, by using a half mirror 8 and a prism 9, the light emitted from the image guide 2 is divided into a pair of eyepieces], 0
, 10, and each eyepiece 3,
Three-dimensional viewing was made possible by disposing shutters 7 and 7 and shutters 'l' and T', which are alternately opened and closed in synchronization 1-, in front of the camera 3 so that the above-mentioned images can be viewed alternately. However, in this configuration, the objective systems 4, 4 have shutters 7.
7, the structure of the distal end of the endoscope becomes complicated, and the distal end becomes thick, which is undesirable because it causes great pain when swallowing.

In addition, since both of the above two conventional examples use two objective lenses, the number of parts is large, and it is necessary to improve the precision of the objective lenses to reduce variations in the angle of view of the two objective lenses. As a result, there was a problem that manufacturing costs increased.

Purpose: In view of the above-mentioned problems, the present invention aims to provide a stereoscopic endoscope in which the entire body cavity insertion portion including the distal end portion is made thinner, and the manufacturing cost is reduced.

Overview The stereoscopic endoscope according to the present invention includes a rotating member pivotally attached to the distal end of the endoscope, and a rotating member fixed to the rotating member such that the optical axis does not coincide with the rotation axis of the rotating member. By comprising an objective lens and a pair of eyepiece systems that respectively observe images when the objective lens assumes two different positions due to rotation of the rotating member, it is possible to observe two parallax object images. This is how it was done.

EXAMPLE Below, the present invention will be described in detail based on an example shown in FIGS. 3 to 8. FIG. 3 is a schematic sectional view showing the structure of the tip of an endoscope, and FIG. It is a schematic cross-sectional view showing the configuration of the entire mirror, in which 11 is an endoscope tip portion provided with a cylindrical recess 11a on the front end surface, 12 is a motor provided in the endoscope tip portion ll, and 13 is a motor provided in the endoscope tip portion ll. A rotating member 1 fixed to the rotating shaft 12a of the motor 12 while housed in the four parts 11a.
4 is a transparent lid that liquid-tightly covers the recess 11a; 1;
5 is an objective lens provided in the rotating member 13 so that its optical axis does not coincide with the rotation axis 12a, and 16 is an objective lens 1.
A solid-state imaging device 17 is provided at the imaging position of 5, and the solid-state imaging device 17 is provided in the endoscope tip 11, and its input end is connected to the light source 18, and its output end is near the external protruding end of the rotation shaft 12a. A first light guide facing the bottom of the recess 11a, 1
Reference numeral 9 indicates a second light guide provided within the rotating member 13, and its input end faces the output end of the first light guide 17 near the rotating member attachment position of the rotating shaft 12a; An illumination lens is disposed close to the output end of the second light guide 19, and 21 is a conducting wire for sending the output signal of the solid-state imaging device 16 to a pair of picture tubes 23 and 23 via a signal processing circuit 22. . The first light guide 17 is made by bundling optical fibers to form a through hole 17a' (i7) extending from the output end surface to the side surface as shown in FIG. The shaft 12a is made to reach the rotating member 13.The incident end face of the second light guide 190 has a ring shape corresponding to the outgoing end face of the first light guide 17.The conducting wire 21 is For example, as shown in FIG. 5, it enters into the rotating member 13 along the outer peripheral surface of the first light guide 17 and comes into sliding contact with the ring-shaped electrode 24 connected to the solid-state imaging device 16.

6 is a block diagram of the signal processing circuit 22, and FIG. 7 is a timing chart showing the operation of the signal processing circuit 220. When a motor drive signal is output from the control circuit 31, the motor drive circuit 32 controls the motor 12 at 180. Rotate intermittently in ° steps. The motor 12 is provided with a pulse generator 33 for position detection immediately before the stop position every 180°, and the pulse generator 33 generates a PG pulse as a signal indicating that the rotation operation of the motor 12 has ended at each step. is supplied to the control circuit 31. The control circuit 31 supplies a drive signal to the solid-state imaging device drive circuit 34 at a timing slightly delayed from the input of the PG pulse, thereby starting reading out signals from the solid-state imaging device 16. The output signal of the solid-state imaging device 16 is amplified by a preamplifier 35 and then supplied to a sample and hold circuit 36. However, since the sampling pulse generation circuit, which will be described later, does not operate at first, no sampling pulse is supplied to the sample hold circuit 36, and as a result, the output signal is not sampled and is not supplied to subsequent circuits. The control circuit 31 issues the solid-state imaging device drive signal again when T7 seconds have elapsed, thereby reading out the signal from the solid-state imaging device 16.
7 is driven, a sampling pulse is supplied to the sample and hold circuit 36, and as a result, the output signal is sampled. This output signal is sent to the color separation circuit 38
, G, and H, and process circuits 39 , 40 .

After being processed at 41, the signals are outputted as color video signals by a color encoder 42, stored in a frame memory 43, and displayed on one of the picture tubes 33. When T1 seconds have elapsed, the control circuit 31 again outputs a motor drive signal, causing the motor drive circuit 32 to rotate the motor 12 by 180°.
A PG pulse is output from the control circuit 31. The solid-state imaging device 16 is driven via the solid-state imaging device drive circuit 34, but similarly to the above, the sampling pulse is applied to the signal read out from the solid-state imaging device 16 by the solid-state imaging device drive signal immediately after the PG pulse is output. Since no signal is output, this signal is discarded. After this, only the signal read out by the solid-state imaging device drive circuit 34 in accordance with the solid-state imaging device drive signal from the control circuit 31 when T1 seconds has elapsed is sampled by the sample hold circuit 36, and the frame is processed through the same processing as described above. While being stored in the memory 44,
The image is displayed on the other picture tube 33. In addition, frame memory 4
The video signals stored in 3.44 are alternately replaced with new video signals that are supplied one after another. Further, the period of the motor drive signal is set to be shorter than the afterimage time of the human eye.

Since the stereoscopic endoscope according to the present invention is constructed as described above, when the rotating member 13 is rotated by the motor 12, the objective lens 15 is moved to the rotating shaft 12 as shown in FIG.
The images taken at these different positions, that is, the images A and B with two parallaxes, are received by the solid-state imaging device 16 and converted into signals, and then converted into signals. A pair of picture tubes 33 via the processing circuit 22
゜33 respectively. Therefore, these images A and B
If you look at it with your left and right eyes, you can see stereoscopically.

In this embodiment, only the signals accumulated in the solid-state imaging device 16 are sampled at T1 seconds shown in FIG. Since the signals accumulated during this process are discarded, the image does not fade and a clear image can be obtained. Further, the rotating member 13 may be alternately rotated by 180° in the left and right directions as shown in FIG.

In that case, the rotating member 13 has a pair of pins 13a.

13a at a 180° symmetrical position, and the endoscope tip 11
A stopper 11b is provided to move the rotating member 13 to the left and right
What is necessary is to lock it every 0° rotation.

Further, in this case, even if the conducting wire 21 is introduced into the rotating member 13 as it is along the inner circumferential surface of the first light guide 17, it will not be twisted and the structure will be simple, which is preferable. Alternatively, the rotating shaft 12a of the motor 12 may be made hollow and the conducting wire 11 may be passed through it.

The operating principle of the stereoscopic endoscope according to the present invention has been explained above. Since this endoscope uses only one objective lens 15, the space required for the objective lens is small, and as a result, the distal end The entire body cavity insertion portion including 11 becomes thinner. Further, for the same reason, the number of parts is reduced, and since an image with parallax can be obtained with a single objective lens 15, there is no need to increase the accuracy of the objective lens so much, so manufacturing costs are reduced.

FIG. 1O shows a second embodiment, in which a light emitting element 45, such as an LED, is used in place of the light guide 17, 19 and the illumination lens 20. FIG. 11 shows a third embodiment, in which the rotating shaft 12a of the motor 120 is set perpendicular to the longitudinal direction of the endoscope tip 11 to enable side viewing. Of course, if the rotating shaft 12a of the motor 120 is set obliquely, a perspective view is also possible.

Effects of the Invention As described above, the stereoscopic endoscope according to the present invention has important practical advantages in that the entire body cavity insertion part including the distal end becomes dark blue and the manufacturing cost is low.

[Brief explanation of the drawing]

FIG. 1 and FIG. 2 are schematic diagrams showing conventional optical systems, respectively;
3(A) and 3(B) are a schematic sectional view and a front view, respectively, showing the structure of the distal end of an embodiment of the stereoscopic endoscope according to the present invention, and FIG. 4 shows the structure of the entire embodiment. 5 is a perspective view of essential parts of the above embodiment, FIG. 6 is a block diagram of the signal processing circuit 22 of the above embodiment, and FIG. 7 is a timing chart showing the operation of the signal processing circuit 22. Fig. 8 is a front view showing a change in the position of the objective lens 15 due to rotation in one direction, Fig. 9 is a front view showing a change in position of the objective lens 15 due to alternating left and right rotation, and Fig. 10 shows the structure of the second embodiment. The schematic sectional view and FIGS. 11(A) and 11(B) are a schematic sectional view and a front view, respectively, showing the structure of the third embodiment. 11...Endoscope tip, 12...Motor, 13
...Rotating member, 14...Transparent lid, 15...
・Objective lens, 16... Solid-state imaging device, 17...
・First light guide, 18°...Light source, 19...
Second light guide, 20...Illumination lens, 21...
... Conductor, 22... Signal processing circuit, 23... Picture tube. Ward C 108) Lr, ↑ U

Claims (1)

[Claims] a rotating member pivotally mounted to the distal end of the endoscope; an objective lens fixed to the rotating member such that its optical axis does not coincide with the rotating axis of the rotating member; and rotation of the rotating member to rotate the objective lens. A stereoscopic endoscope equipped with a pair of eyepiece systems for respectively observing images when the lens takes two different positions.