JPS61282815A - Hard endoscpe - Google Patents

Abstract

PURPOSE:To prevent the drop-out of an image and the breaking of an optical member by providing spacer members at suitable intervals between the inside wall of a straight outside pipe and the outside periphery of the optical member to be inserted to the inside of the outside pipe thereby maintaining the space. CONSTITUTION:The spacer members 3 are provided at suitable intervals between the inside periphery of the straight outside pipe 1 and the outside periphery of the optical member to be inserted to the inside of the outside pipe, for example, a relay lens 2. A top end member and eyepiece part are provided to both ends of the pipe 1 and an optical fiber bundle for illumination is inserted into the space between the pipe 1 and the member 2. The crescent hiding of the visual field and the breaking of the lens are thereby prevented even if external force is exerted to the insertion part of the endoscope.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a rigid endoscope.

[Prior Art] In recent years, an elongated insertion section is inserted into a body cavity, an objective optical system formed at the tip of the insertion section forms an image of a target region such as an organ inside the body cavity, and the image is transmitted via an image transmission means. Endoscopes that allow observation at the proximal eyepiece outside the body cavity are now widely used for observation and diagnosis. This endoscope has a flexible insertion section that allows observation of the target area within the body cavity through a curved path from the oral cavity, etc., and a rigid endoscope that has a rigid insertion section that allows observation of the target area inside the body cavity through a curved path. There is a rigid endoscope that is inserted into the

This rigid endoscope has a relay lens fitted into a lens storage tube with a spacer ring in between, as disclosed in Japanese Utility Model Application No. 59-27519.

In addition, as disclosed in Tokutokuma DE3113110, the insertion section is resistant to bending of a long and narrow scope.
In order to improve performance, the diameter of the central part of the relay rod lens is made smaller than that of both ends, so that both ends fit into the lens tube.

[Problems to be Solved by the Invention] In the conventional technology, with a rigid endoscope having an insertion section with a small outer diameter and a long effective length, the insertion section bends due to external force and cannot pass through the relay lens system. There were problems such as part of the light beam being blocked, resulting in a three-month field of view, and bending of the insertion part due to external force, which caused cracks in the relay lens system and peeling of the adhesive on the lens joint surface. .

In addition, the center of the O Rad lens is thinner than both ends.
There was a problem in that the manufacturing of the lens was complicated. Therefore, the present invention was made with attention to the above-mentioned problems, and aims to reduce cracking of the lens system, peeling of adhesive on the joint surface, lack of visual field, etc. due to bending of the insertion part due to external force. purpose.

[Means for Solving the Problems] As shown in FIG.
A gap member 3 is provided between the outer wall and a part of the outer wall.

[Function] A gap member 3 is formed between the inner wall of the tube 1 and a part of the outer wall of the optical member 2.
was installed to maintain a gap between the inner and outer walls.

[Example] FIGS. 2 and 3 are diagrams showing a first embodiment of the present invention.

The rigid endoscope 110 has an elongated insertion section 1 that can be inserted into a body cavity.
2 and an eyepiece section 14 formed at the rear end of the insertion section 12.

The insertion section 12 is made up of an outer tube 1 tube 6 made of a small diameter metal pipe, and a white cloud 18 having a diameter smaller than the inner diameter of the outer tube 16.The white cloud 18 is inserted eccentrically with respect to the outer tube 16. The gap between the outer tube 16 and the inner tube 18 is filled with an optical fiber bundle 20 for illumination.

The rear end of the outer tube 16 is joined to the eyepiece main body 22, and the inner tube 18 is joined to seven flange 24 fixed inside the eyepiece main body 22. Further, the eyepiece main body 22 is provided with an optical fiber bundle base 26, and an optical fiber 118 for illumination.
The rear end of the M bundle 20 is attached. A concave groove 28 is formed in the entire rear circumference of the eyepiece main body 22, and an O-ring 30 is housed therein. Roughly speaking, a threaded portion 32 is formed at the rear end of the eyepiece main body 22, into which an eyepiece cover 34 is fitted and is watertight with an O-ring 3o. An eyepiece 36 is provided on the rear outer periphery of the eyepiece cover 34, and a rear cover glass 38 is provided on the rear end.

Furthermore, a cylindrical connection fitting 40 is provided inside the eyepiece main body 22.
is fitted by a threaded portion 42, and a pin 44 is provided at the rear end of the inner surface of this connecting fitting 40.

Adjustment ring 46 is fixed. Further, an eyepiece frame 50 to which the eyepiece system 48 is fixed by adhesive is attached to the adjustment ring 46 at a screw portion 5.
2 and fixed by a retaining nut 54.

A tip member 58 to which a tip cover glass 56 is adhesively fixed is attached to the tip of the inner tube 18, and a lens tube 64 having an objective lens holder 60 and a relay lens holder 62 arranged at the rear end of the tip member 58. They are mated. Further, an annular spacing ring 66 is mounted between each lens. And inside i! Inside the lens tube 18, a relay lens 62 is inserted behind the lens tube 64 for transmitting an image at the tip. Each of these lenses is smaller than the inner diameter of the inner tube 18;
An annular spacing ring 74 having a gap 72 formed at both ends is fitted between the inner tube 18 and the relay lens $62. The outer diameter of the spacing ring 74 fits into the inner tube 18, and the relay lens also fits into the gap 72 at both ends of the inner circumferential surface, and the portion of the inner circumferential surface other than both ends is smaller than the outer diameter of the lens. It is smaller and maintains the distance between each lens.

Furthermore, the relay lens 62 at the rear end on the eyepiece side is connected to the lens tube 7.
8 and fixed to the rear end of the inner tube 18, and is further biased toward the distal end by a convex portion 80, a spring 82, and a lens holder 84 provided on the inner peripheral surface of the connecting fitting 4o.

Based on the configuration described above, in the first embodiment, rigid endoscopy is used to observe the inside of the body! [Insert the insertion section 12 of 10, and emit illumination light from the tip to illuminate the observation site. The observation image is then transmitted by the relay lens 62 to the rear eyepiece section 14 for observation. At this time, even if force is applied to the elongated insertion section 12 when the rigid endoscope 10 is inserted into or withdrawn from the body, the gap 72 of the spacing ring 74 prevents the relay lenses 62 from entering the body. There is no direct contact with tube 18.

Therefore, a part of the light ray passing through the relay lens system is not blocked and the field of view is not cut off in a crescent shape, and cracks in the lens and peeling of the lens joint surface do not occur.

FIG. 4 is a diagram showing a second embodiment of the present invention, in which the same parts as in the first embodiment are denoted by the same reference numerals, and details are omitted. In this embodiment, in order to fit both ends of the relay lens 62, the inner tube 88 is made to protrude in the inner diameter direction to form a protrusion 90.

Therefore, the shape of the spacer ring is simplified and workability is improved.

FIG. 5 shows a third embodiment, in which an annular spacing ring 92 is embedded in an elastic member 94 such as rubber, and a spacing is maintained between each relay lens 62 by a metal spacing ring 92. The gap between the inner tube 18 and the relay lens 62 is maintained by an elastic member 94.

FIG. 6 shows a fourth embodiment, in which grooves 96 are provided near both ends of the relay lens 62, and O-rings 98 are fitted into the grooves to maintain a gap between the inner tube 18 and the relay lens 62. be.

FIG. 7 is a view showing a fifth embodiment, in which an annular member 100 is provided to maintain a gap between the inner tube 18 and the relay lens 62, and the connecting portion 102 also connects the inner tube as shown in FIG. A coil 104 may be provided between the relay lens 18 and the relay lens 62.

[Effects of the Invention] By maintaining the gap between the inner tube and the relay lens with a gap member, even if force is applied to the insertion part, the field of view will not be cut in a crescent shape, the lens will be cracked, and the lens will not be damaged. There is no peeling of the joint surface, and good observation is always possible.

[Brief explanation of drawings]

FIG. 1 is a diagram for explaining the present invention, FIG. 2 is an overall sectional view showing the first embodiment, FIG. 3 is a partial sectional view of the first embodiment, and FIG.
The figure is a partial sectional view showing the second embodiment, FIG. 5 is a partial sectional view showing the third embodiment, FIG. 6 is a partial sectional view showing the fourth embodiment, and FIG. 7 is a partial sectional view showing the fifth embodiment. A partial sectional view, FIG. 8, is a diagram showing a modification. 10: Within hardness? J! Mirror, 12: Insertion section, 14: Eyepiece section,
18: Inner tube, 62: Relay lens, 72: Gap, 74
... Spacing ring, 90: Protrusion, 94: Elastic member, 98:
0 ring, 100: Annular member diameter 9' Figure 4 - Figure 5 Figure 6

Claims (1)

[Claims] A rigid endoscope that transmits an image using an optical member housed in a long and thin tube, characterized in that a gap member is provided between the inner wall of the tube and the outer wall of a portion of the optical member to maintain a gap. Rigid endoscope.