JPS62209509A - Endoscope - Google Patents

Abstract

PURPOSE:To switch a visual field and to obtain an erect image in the eyepiece part side by twisting an image guide consisting of an optical fiber bundle at the visual field switching time between side sight and straight sight. CONSTITUTION:In case of side sight, a side sight image A is made incident as an inverted image by a prism 22 for side sight and is converted to the original erect image by a lens system 23 and is made incident on an image guide 34. Consequently, an erect image (a) is obtained on the side of an eyepiece part 36. In case of straight sight, a straight sight image A' is made incident on the image guide 34 as an inverted image by a lens 20 for straight sight, but the image is inverted on the way of the image guide because the image guide 34 is twisted at 180 deg. and consists of an optical fiber bundle. Consequently, the erect image (a) is obtained on the side of the eyepiece part 36.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to an endoscope, and particularly to an endoscope that can be switched between direct viewing and side viewing.

[Background of the invention]

The curved portion of the insertion portion of the endoscope is formed to be flexible and can be bent in a desired observation direction. Furthermore, there are two types of endoscopes: a direct-viewing endoscope that observes the direction (forward) along the axis of the insertion section, and a side-viewing endoscope that observes the side in a direction perpendicular to the axis. In any type of endoscope, the viewing direction can be changed by curving the insertion section. However, the bending range is limited depending on the size of the body cavity to be observed, and there are cases where a necessary part cannot be observed or a bending operation cannot be performed quickly. For this reason, it has been considered to expand the observation range by equipping the tip of the endoscope insertion section with two types of objective optical systems, one for direct viewing and one for side viewing, and making it possible to switch and connect an image guide to these systems. There is.

However, if the image obtained on the eyepiece side is set to be an erect image when using the direct viewing optical system, the image obtained when using the side viewing optical system using a prism or reflector is reversed, resulting in an inverted image with the left and right sides reversed. There is an obvious problem. Conventionally, in order to solve this problem, an image rotator made of a trapezoidal prism was arranged, and the image rotator was rotated in conjunction with switching from direct view to side view, thereby obtaining an erect image. There is. However, this method requires an image rotator, and the image rotator must be rotated in conjunction with switching the viewing direction, resulting in a complicated structure.

[Purpose of the invention]

The present invention has been made in view of these circumstances, and is an endoscope that can be switched between direct view and side view, has a simple structure, can always obtain an erect image on the eyepiece side, and is easy to operate. The aim is to propose an endoscope that can provide convenience.

[Summary of the invention]

In order to achieve the above object, the present invention includes a side-view objective optical system equipped with an observation window on the outer peripheral surface of the distal end of an endoscope insertion section, and a direct-view objective optical system equipped with an observation window on the front surface. In the endoscope, the endoscope is configured to be switchable so that the tip of the image guide, the rear end of which is disposed facing the eyepiece of the endoscope manual operating section, can be disposed facing each of the optical systems. The objective optical system and the direct-view objective optical system are arranged approximately 180° apart, and the tip of the image guide is arranged opposite to one of the objective optical systems, and is twisted approximately 180° when switching to the other objective optical system. It is characterized by being placed opposite to the optical system.

〔Example〕

Hereinafter, preferred embodiments of the endoscope according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows the general shape of the endoscope, with reference numeral 10 indicating an endoscope insertion section, 12 indicating a hand-operated operation section including a bending operation knob, a water supply button, a suction button, an eyepiece, etc., and 14 indicating the endoscope insertion section. , a control unit 16 equipped with a light source, etc., and a manual operation section 12
It is a connecting part that connects the A curved section 18 is formed at the distal end of the endoscope insertion section 10, and a flexible section 19 is formed following the curved section 18.

FIG. 2 shows the internal structure of the curved portion 18, which includes a direct viewing lens system 20 as a direct viewing objective optical system on the distal end side,
The side-viewing prism 22 constituting the side-viewing objective optical system is 180' apart from the central axis X of the curved portion 18 and fixed in symmetrical positions with respect to each other. A lens system 23 is arranged behind the prism 22. The direct viewing lens system 20, the side viewing prism 22, and the lens system 23 are arranged 180' apart from each other. A direct viewing light guide head 24 that illuminates the front and a side viewing light guide head 26 that illuminates the side are fixed near the lens system 20 and prism 22, respectively. The light guide head 24, 26 may be made of bundled fibers, or may be a quartz rod or a single fiber with a large core diameter.

lens system 20.23 and each light guide rad 24.
A switching member 28 made of a spur gear rotatable about the central axis X is provided behind the switching member 26 . A driving gear 30 meshes with this switching member 28, and the driving gear 30 can be rotated manually or driven by a motor via an operating shaft 32 guided to the hand operating section 12 side.

One image guide 34 and one light guide 36 are connected to the switching member 28 . Image guide 34
The light guides 36 are made of optical fiber bundles, and the tips of the light guides 36 pass through the switching member 28 so that they can come into sliding contact with the rear ends of the lens systems 2Q, 23 and the light guide heads 24, 26.

Then, the switching member 28 is moved 180' by the driving gear 30.
When rotated in the forward and reverse directions, the image guide 34 and the light guide 36 are connected to the direct viewing lens system 20 and the direct viewing light guide head 24, or to the side viewing prism 22 and the side viewing light guide head 26, respectively, and the eyepiece portion An image for direct viewing or an image for side viewing is sent to the 36 side via the image guide 34.

FIG. 3 shows changes in the shape of the image guide 34. The solid line indicates the side view state, and the imaginary line indicates the direct view state. In the direct view state, the image guide 34 is connected to the 18
Twisted by 0°.

During side viewing, the side-viewing image A enters the side-viewing prism 22 as an inverted image, is converted into the original erect image by the lens system 23, and enters the image guide 34.

Therefore, an erect image a is obtained on the eyepiece section 36 side.

Further, during direct viewing, the direct viewing image A' is incident on the image guide 34 in an inverted state by the direct viewing lens system 20, but since the image guide 34 is twisted by 1800 degrees and the image guide 34 is formed of an optical fiber bundle, The image is turned upside down in the middle. Therefore, an erect image a is still obtained on the eyepiece section 36 side.

Therefore, according to the endoscope according to this embodiment, an erect image can always be obtained even when switching between direct viewing and side viewing, which is extremely convenient for performing various treatments.

Further, in the above embodiment, the case of switching from side view to direct view has been described, but the image guide 34 may be first set to the direct view side, and then switched to the side view side at 180'[1.

Further, in the embodiment described above, the light guide 36 is attached to a rotating member and rotated at the same time as switching, but it goes without saying that the present invention can also be applied to a fixed type light guide 36.

〔Effect of the invention〕

As explained above, according to the present invention, the field of view is switched by twisting the 1' image guide made of an optical fiber bundle when changing the field of view between side view and direct view. You can get a royal image with .

[Brief explanation of drawings]

FIG. 1 is an overall configuration diagram showing an embodiment of an endoscope according to the present invention, FIG. 2 is a perspective view showing the main structure of FIG. 1, and FIG. 3 is an explanatory diagram of the operation. 20... Lens system for direct viewing, 22... Prism,
23... Lens system for side viewing, 28... Switching member, 34... Image guide.

Claims (1)

[Claims] The endoscope insertion section has a side-view objective optical system with an observation window on the outer peripheral surface of the distal end, and a direct-view objective optical system with an observation window on the front. In an endoscope configured to be switchable so that the tip of an image guide disposed facing the eyepiece can be disposed facing each of the optical systems, the side-viewing objective optical system and the direct-viewing objective optical system have approximately 180 mm diameter. The tips of the image guides are placed opposite to one of the objective optics, and the tip of the image guide is placed at a distance of approximately 1
An endoscope characterized in that it is twisted by 80 degrees and placed opposite to the other objective optical system.