JPH034885B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rigid endoscope whose observation optical system can be easily adjusted.

In recent years, by inserting a long and thin insertion section into a body cavity, organs within the body cavity can be observed, and if necessary, in-vivo tissues can be collected using forceps inserted through the forceps channel to diagnose the affected area in detail. Medical endoscopes are widely used. or,
In the industrial field, it is also used for maintenance purposes, such as observing the condition inside the pipes of boilers, chemical plants, etc., or collecting and inspecting deposits on the inner surface of the pipes.

The above-mentioned endoscope is a flexible endoscope with a flexible insertion part,
The insertion section is roughly divided into rigid endoscopes, which have a rigid insertion section.For the latter, a relay optical system (relay lens system) with excellent resolution is used as an image transmission means inserted through the insertion section. It is used.

Therefore, especially in rigid endoscopes, the performance of the observation optical system is greatly affected by whether or not the observation optical system is adjusted correctly.
Adjustment of this observation optical system is a very important adjustment factor.

In the adjustment of the observation optical system, among the objective optical system, the relay optical system, and the eyepiece optical system, the objective optical system in particular greatly contributes to the optical performance.

In the conventional example, the observation optical system is constructed by housing the objective optical system and the relay optical system in one pipe and attaching the eyepiece optical system to the pipe. Even when adjusting them alone, the objective optical system and relay optical system must be disassembled, and the entire system must be readjusted. Therefore, the adjustment work becomes complicated, it is difficult to adjust to the best condition, and it is difficult to fully perform the function as an observation optical system.

Furthermore, there is an endoscope 1 having a configuration as shown in FIG. 1, which is disclosed in Japanese Patent Application Laid-open No. 55-155642.

As shown in the figure, the elongated lens barrel 2 includes lens systems 3a, 3b, and 3 that serve as objective systems and image transmission means.
c, 3d, 3e, and 3f are arranged, and a variable magnification eyepiece 5 is arranged in the eyepiece section 4 behind them.

The lens barrel 2 can be attached and detached and divided into multiple parts,
By changing the focal length of the lens systems connected in series, the magnification, observation distance, optical length, etc. can be varied stepwise depending on the object to be observed.

However, in this conventional example, since the lens barrel 2 whose side outer periphery is exposed to the outside can be divided,
Liquid-tightness and air-tightness at each connection part cannot be maintained sufficiently. Therefore, it is almost impossible to actually use it as a rigid endoscope, which requires constant disinfection, cleaning, sterilization, etc. before and after use.

In addition, in the conventional example described above, the light guide fibers that transmit illumination light are divided into short sections and connected, so the amount of light that should be transmitted at each connection part decreases, and the amount of illumination light may be insufficient, or depending on the combination. There is an inconvenience that variations occur in the amount of illumination light, making it necessary to adjust the amount of illumination light, which imposes a burden on the operator. Therefore, there is a possibility that the operator's diagnosis or treatment using forceps or the like will be hindered.

The present invention has been made in view of the above-mentioned points, and includes a cylindrical body that accommodates an objective optical system extending from the inside of a pipe-shaped insertion part mantle to a rear eyepiece section, a cylindrical body that houses a relay optical system, and an eyepiece optical system. Adjustment work can be facilitated by connecting and fixing at least two or more adjacent cylinders to the cylinder housing the system and inserting them into the inner tube for housing the observation optical system to form the observation optical system. It is an object of the present invention to provide a rigid endoscope that can be easily set to the best condition.

The present invention will be specifically described below with reference to the drawings.

Figures 2 to 4 relate to the first embodiment;
The figure shows a perspective type rigid endoscope according to the first embodiment, FIG. 3 shows an exploded view of the configuration shown in FIG. 2, and FIG. 4 shows the objective and relay optical system which are the main parts of the first embodiment. Parts are shown enlarged.

In these figures, the rigid endoscope 11 of the first embodiment has an elongated insertion section 12 inserted into a body cavity.
and an operating section 13 formed at the rear end of the insertion section 12;
The eyepiece section 14 is formed on the rear end side of the operation section 13.

The insertion portion 12 is covered with a hard pipe-shaped outer tube (mantle tube) 15, and the rear end of this outer tube 15 is provided with a light guide cap 16 on the side to which a light guide cable (not shown) is attached. It is fixed to the inner circumferential surface of the open front end of the operating portion 13 by brazing or the like.

On the rear end side of the operating section 13, there is a connecting member 1 whose front end outer circumferential surface can be attached and detached by screwing onto the rear end inner circumferential surface.
7 is connected, and an O-ring 18 is disposed in a concave portion on the outer periphery of this connecting member 17 for watertightness, and a threaded portion is formed on the outer periphery of the rear end side adjacent to this concave portion.
The inner peripheral surface on the front end side abuts the ring 18, and is covered with an outer cylinder 19 (eyepiece part) in which a screw hole is formed to be screwed into the threaded part.

On the other hand, inside the outer tube 15, an inner tube 20 serving as an optical system storage tube is provided in contact with the upper inner circumferential surface of the outer tube 15.
is arranged, and the rear end side of this inner tube 20 is provided with an operating section 13
It extends further to the rear and is fitted and fixed to the inner circumferential surface of a small-diameter through hole that fits into the outer diameter of the inner tube 20 of the connecting member 17 . In fixing using the connecting member 17, the diameter of the front end of the through hole that fits into the outer diameter of the inner tube 20 is expanded, an O-ring 21 is housed inside, and a retaining ring 22 having a thread formed on the outer periphery is used to secure the O-ring 21. The O-ring 21 is held between the inner tube 20 and the outer periphery of the inner tube 20 to prevent gases such as water vapor from entering the rear side of the inner tube 20 (or the connecting member 17).

For example, a hemisphere is cut out at an angle on the distal end side of the outer tube 15 to form a perspective opening for observation and illumination, and a cover glass mounting frame 23 is fixed to the distal end of the inner tube 20 facing the opening. A fixing frame 24 is press-fitted into the cover glass mounting frame 23 to sandwich the cover glass 25, and the cover glass 25 is mounted so as to maintain air-tightness and liquid-tightness.

On the other hand, a light guide fiber 26 is inserted into a gap having a substantially crescent-shaped cross section between the eccentrically arranged outer circumference of the inner tube 20 and the inner circumference of the outer tube 15 so as to transmit the illumination light and emit it from the end surface. , this rear end side is curved at a substantially right angle in the operation part 13 and fixed with a light guide base 16, and the illumination light supplied from a light source device (not shown) via a light guide cable is attached to the tip of the inner tube 20. The light is emitted from the end face of the light guide fiber 26, which is curved along the outer periphery of the cover glass mounting frame 23 and the hemispherical circumference of the outer tube 15, and is configured to illuminate an object in front in the oblique direction.

By the way, as shown in FIG. 3 or 4, inside the inner tube 20, there is a cylindrical objective outer frame (objective optical system housing tube) 27, and its front end is fitted into the rear end of the objective outer frame 27. A cylindrical relay optical system storage tube 28 that can be integrated together is fitted and inserted.

A front objective lens frame 29 is fixed to the front end side of the objective outer frame 27 by adhesive or the like, and the peripheral edge where the objective front lens 30 comes into contact with the objective front lens frame 29 is fixed to the objective front lens frame by adhesive or the like. It is fixed at 29. The front end surface of an objective prism 31 is in contact with and fixed to the rear end surface of the front objective lens frame 29 to which the front objective lens 30 is fixed. The surfaces are fixed so that they are in contact.

Behind the objective lens 32 is a rear objective lens 3 fixed to the objective outer frame 27 via an objective inner frame 33.
4 is fixed, and the rear end side of this objective outer frame 27 is stepped and has a small diameter so that it can be fitted into a spacer 35 that is fitted and fixed to the inner peripheral surface of the front end of the relay optical system housing tube 28. The objective outer frame 27 and the relay optical system housing tube 28 when these are integrated
The outer diameter is made almost the same as the inner diameter of the inner tube 20 so that it can be fitted into the inner tube 20.

The spacer ring 35 is arranged in the relay optical system housing tube 28 in such a way that the front side periphery is in contact with the spacer ring 35, and the rear side is also in contact with a spacer ring (hereinafter the same reference numeral 36) having each predetermined length. A relay rod lens 37, a relay cemented lens 38, etc. serving as image transmission means are fixed at predetermined intervals, and in the illustration, the relay rod is partially protruded from the rear end of the relay optical system housing tube 28. A lens 37' is fixed with adhesive or the like.

The relay optical system such as the relay rod lens 37 and the relay cemented lens 38 is housed, and the objective outer frame 27
The relay optical system housing tube 28 integrated with the inner tube 2
At the rear of the relay rod lens 37', which is inserted into the inner periphery of the connecting member 17 and fixed at a predetermined position, is a screw 39 on the inner periphery of the enlarged rear end of the connecting member 17. Stopped eyepiece adjustment tube 40
A cylindrical eyepiece frame 42 whose front end side is fitted into the rear end side and an eyepiece system 41 attached to the rear end side is fixed with a screw 43, and a recess is formed on the front end side of this eyepiece frame 42 to form a field stop 44. It is accommodated. Further, the eyepiece system 41 is fitted and accommodated in an open end with a slightly enlarged rear end side of the eyepiece frame 42, and a fixed frame 45 has a protruding edge that abuts against the peripheral edge of the rear end of the eyepiece system 41. The eyepiece lens system 41 is fixed by screwing it onto the outer periphery of the eyepiece frame 42.

Eyepiece section 14 outer cylinder 1 that houses these eyepiece optical systems
A cover glass 46 (eyepiece) is provided in the opening at the rear end of 9.
However, the front end side of the cover glass fixing frame 47 is attached to the outer cylinder 19.
By press-fitting into the outer circumference of the rear end which has a small diameter,
The cover glass 46 is fixed by pressing the tapered portion of the rear end periphery forward. An eyepiece 48 is screwed from the rear end side of the outer periphery of the outer tube 19 to which the cover glass fixing frame 47 is attached.

In the first embodiment configured in this way,
Objective outer frame 27 housing the objective optical system within the inner tube 20
It is characterized in that the relay optical system storage tube 28 and the relay optical system housing tube 28 that house the relay optical system therein are configured to fit and be integrated.

Therefore, according to the first embodiment, the objective optical system, the relay optical system, and the eyepiece optical system are housed in independent cylindrical members, that is, the objective outer frame 27, the relay optical system housing tube 28, and the eyepiece frame 42. Since it has been
All you have to do is assemble and adjust each part individually. Then, the objective optical system and the relay optical system after each adjustment are combined and integrated, and the insertion portion 12
By inserting the integrated operating part 13 into the inner tube 20 from behind and combining it with the adjusted eyepiece optical system, it is possible to complete an observation optical system that can fully perform a predetermined function.

The above-mentioned adjustment work when assembling each optical system may be performed by preparing highly accurate prototypes for each optical system and replacing the parts to be adjusted with the prototypes. Further, when adjusting an individually assembled optical system, for example, an objective system, it is performed by observing an image in combination with prototypes of a relay lens system and an eyepiece optical system. In this case, the cause of the poor resolution is not caused by anything other than the objective system, so it is easy to eliminate the cause. The same thing can be done for other optical systems.

As described above, in the first embodiment, each optical system is provided as a separate member, and by combining these, a predetermined observation optical system is completed. Therefore, each optical system can be adjusted. It also has the advantage that the combined optical system can be easily adjusted. Further, in the case of maintenance or repair, each optical system can be separated, so maintenance and repair can be easily performed.

5 to 8 relate to the second embodiment, and FIG.
The figure shows a perspective type rigid endoscope according to the second embodiment, FIG. 6 shows the second embodiment exploded, and FIG. 7 shows the second embodiment.
An observation optical system according to an embodiment is shown, and FIG. 8 shows an exploded view of the observation optical system of FIG. 7.

In these figures, the rigid endoscope 51 of the second embodiment is configured such that an eyepiece optical system can be further integrated with the rear end of the relay optical system housing tube 28 of the first embodiment by screwing.

That is, in the second embodiment, as in the first embodiment, a connecting member 17' is attached to the rear end of the inner tube 20' so that the O-ring 21 is kept liquid-tight by a holding ring 22. Similar to the first embodiment, this connecting member 17' accommodates the O-ring 18 inside the eyepiece portion 1.
It is configured to be covered with four outer cylinders 19.

In this embodiment, the eyepiece adjusting tube 40' to which the front end side of the eyepiece frame 42 is fixed is not attached to the rear end side of the connecting member 17' as in the first embodiment, but is attached via an intermediate tube body 52. It is attached to the rear end of the relay optical system housing tube 28.

The intermediate cylindrical body 52 has an inner diameter that fits into the outer periphery of the relay optical system storage tube 28, and has an enlarged diameter on the rear end side and a threaded part formed on the inner peripheral surface, into which it is screwed. A ring-shaped fixing frame 5 with screws formed on the outer periphery.
3 is accommodated. A projecting edge portion projecting inward is formed on the rear end side of the fixed frame 53, and the relay rod lens 37' is fixed by this projecting edge portion so as to be pressed forward.

Further, the outer periphery of the rear end of the intermediate cylinder 52 is threaded, and the threaded part is screwed into a screw hole formed on the inner periphery of the eyepiece adjustment cylinder 40', so that the eyepiece adjustment cylinder 40' is housed. There is.

In this way, the objective outer frame 27 is fitted and attached to the front end of the relay optical system housing tube 28, as in the first embodiment, and furthermore, in this embodiment, the objective outer frame 27 is fitted to the rear end of the relay optical system housing tube 28. The eyepiece frame 42 can be integrally attached via an intervening member, and the integrated observation optical system 54 is inserted into the inner tube 20' after adjustment, and the diameter is expanded in the step shape of the connecting member 17'. The observation optical system fixing frame 55 is fixed to the connecting member 17' by a locking portion 56 protruding inward from the rear end of the observation optical system fixing frame 55 screwed into the rear end opening. The other parts are the same as the first embodiment,
Identical elements are given the same reference numerals.

In the second embodiment, the objective optical system and the relay optical system of the first embodiment are combined after adjustment, respectively, after being inserted into the integrated insertion section 12 and operation section 13 as shown in FIG. compared to being configured to mount a calibrated eyepiece optic.
As shown in FIG. 8, the eyepiece optical system is also integrated before assembly to form the observation optical system 54 shown in FIG. 7, making adjustment easier.

Other effects are substantially the same as those of the first embodiment. Further, the adjustment work for each optical system is the same as in the first embodiment, and the work for adjusting the optical systems in combination is also substantially the same, but is more effective as described above.

In the first and second embodiments, strabismus-type rigid endoscopes 11 and 51 are shown, but the present invention is of course not limited to these, and can be similarly applied to direct-viewing and side-viewing types. It can be applied to
Further, in each of the above-described embodiments, the objective optical system and the relay optical system, and the structure in which the objective optical system, the relay optical system, and the eyepiece optical system can be integrated are shown. It is obvious that the present invention can be applied not only to the examples, but also to combinations in which a relay optical system and an eyepiece optical system can be integrated, for example.

The above-mentioned means for integrating the optical system may be made removable by mechanical connection means such as press-fitting or screwing, or may be connected and fixed by adhesive, soldering, brazing, etc.

As described above, the present invention is configured so that each optical system can be adjusted independently, and after adjustment, at least two or more optical systems are connected to form an observation optical system. Therefore, it has the advantage that each optical system can be easily adjusted to the best condition individually. Therefore, an observation optical system that combines these elements can fully function as an observation optical system. Further, even when maintenance is to be carried out, it can be adjusted separately, which has the advantage that the work can be carried out easily.

[Brief explanation of drawings]

FIG. 1 is a vertical cross-sectional view showing a conventional example, FIGS. 2 to 4 are related to a first embodiment of the present invention, FIG. 2 is a vertical cross-sectional view showing the configuration of the first embodiment, and FIG. FIG. 4 is an enlarged vertical sectional view showing the objective optical system and relay optical system of the first embodiment, and FIGS. 5 to 8 are schematic side views showing the exploded view of the first embodiment. 2
Regarding the embodiments, Fig. 5 is a longitudinal sectional view showing a rigid endoscope of the second embodiment, Fig. 6 is a schematic side view showing the second embodiment in an exploded manner, and Fig. 7 is a schematic side view of the second embodiment. FIG. 8 is a longitudinal sectional view showing the observation optical system in an exploded manner. 11, 51... Rigid endoscope, 12... Insertion section, 13
...Operation unit, 14...Eyepiece, 15...Outer tube, 17,1
7'...Connecting member, 18, 21...O ring, 20,
20'...Inner tube, 25, 46...Cover glass, 26
...Light guide fiber, 27...Objective outer frame (objective optical system storage tube), 28...Relay optical system storage tube, 3
0...Objective front element, 31...Objective prism, 35, 36
... Spacing ring, 37, 37'... Relay rod lens,
38... Relay cemented lens, 40, 40'... Eyepiece adjustment tube, 41... Eyepiece, 42... Eyepiece frame, 45,
53...Fixed frame, 52...Intermediate cylindrical body.

Claims (1)

[Scope of Claims] 1. An optical system storage tube that stores an objective optical system for observation and a relay optical system is provided in the outer tube of the insertion section, and a light guide fiber for illumination is provided on the outer periphery of the optical system storage tube. in a rigid endoscope configured such that an optical image of the object illuminated from the end face of the light guide fiber can be observed through an eyepiece optical system behind the relay optical system, wherein the objective optical system , the relay optical system and the eyepiece optical system are disposed within independent cylindrical members, and at least two or more of these cylindrical members adjacent to each other are connected and can be disposed by passing them through the optical system storage tube. A rigid endoscope featuring: 2. The means for connecting the cylindrical members is a mechanical connecting means such as press-fitting, preferably screwing, or a rigid material according to claim 1, characterized in that the means for connecting the cylindrical members is a mechanical connecting means such as press-fitting, preferably screwing, or connecting by adhesive, soldering, brazing, etc. Endoscope.