JPH0552928B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an endoscope that can change the amount of illumination light that illuminates a subject.

[Technical background of the invention and its problems]

For example, when inspecting the inner surface of a tube as a subject with an industrial endoscope, unless the amount of illumination light emitted from the endoscope is changed according to the thickness of the tube, the inner surface of the tube will be inspected. A problem arises in that the brightness of the inner surface changes greatly, making it difficult to observe well. That is, if the tube has a small diameter, the amount of light must be decreased, and if the tube has a large diameter, it must be increased.

By the way, conventional endoscopes have a built-in illumination lamp in the distal end of the insertion tube, and the illumination lamp is turned on or the illumination light is emitted from a light guide made of an optical fiber bundle with its distal end facing the distal end of the insertion tube. It had a structure that emitted . Therefore, the range of adjustment of the amount of illumination light is limited by the capacity of the light source lamp that inputs illumination light into the illumination lamp and light guide. The drawback was that it could not provide illumination.

[Purpose of the invention]

This invention was made based on the above circumstances, and its purpose is to provide an endoscopic system in which the amount of illumination light can be sufficiently varied to provide good illumination according to the size of the subject. It's about providing a mirror.

[Summary of the invention]

The present invention includes an insertion section having a built-in imaging optical system in its distal end, a ring-shaped illumination unit that is detachably attached to the outer periphery of the distal end of the insertion section, and an illumination unit arranged at equal intervals on the circumference of the ring-shaped illumination unit. The endoscope is equipped with a plurality of light sources.

Therefore, by having the illumination optical system on the circumference around the imaging optical system, the area around the subject can be uniformly illuminated, and the illumination unit can be replaced with one with a different number of light sources. This enables uniform illumination regardless of the size of the subject.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 1 to 3. Reference numeral 1 in FIG. 1 indicates an insertion section of the endoscope. A mounting portion 3 having a smaller diameter than the insertion portion 1 and having a thread 2 formed on its outer peripheral surface is provided at the distal end of the insertion portion 1 . A recess 4 is formed in the center of the mounting portion 3 and is open to the distal end surface of the mounting portion 3, and an objective lens 5 is provided in the recess 4 and held by a holding cylinder 6. A solid-state image sensor 7 is provided on the bottom wall of the recess 4 so as to face the objective lens 5 . This solid-state image sensor 7 is electrically connected to a monitor or a VTR via a video process circuit (not shown). Therefore, the objective lens 5
The optical image obtained by this is converted into an electrical signal by the solid-state image sensor 7, and then subjected to signal processing by a video processing circuit and displayed on a monitor.
It is now being recorded on a VCR. moreover,
A plurality of illumination windows 8 made of cover glass are formed around the objective lens 5 on the distal end surface of the mounting portion 3 . Each illumination window 8 is opposed to the tip of a light guide 9 made of an optical fiber bundle. Illumination light from a light source lamp built into a light source device (not shown) is incident on these light guides 9. Therefore, the illumination light incident on the light guide 9 is emitted from the illumination window 8.

A first lighting unit 10 is detachably attached to the attachment portion 3. This first illumination unit 10 has a ring-shaped main body 11. The inner diameter of this main body 11 is formed to be approximately the same as the outer diameter of the mounting portion 3, and the inner circumferential surface has a female thread 11a.
is provided. Therefore, the main body 11 can be removably screwed onto the mounting portion 3. Further, the main body 11 has a plurality of open mounting recesses 12 formed at predetermined intervals in the circumferential direction on the distal end surface thereof. A lamp 13 is accommodated and held in each mounting recess 12, and a pair of first lead wires 14 connected to these lamps 13 are respectively connected to a pair of ring-shaped contact plates 15 provided on the rear end surface of the main body 11. has been done. In addition, a plurality of first contact pins 17 and second contact pins 18 that contact each of the pair of contact plates 15 are arranged in a predetermined manner in the circumferential direction on the stepped portion 16 formed at the base end of the mounting portion 3. Planted at intervals.
A second lead wire 19 is connected to each contact pin 17, 18, and these second lead wires 19 are connected to a power source (both not shown) via a switch provided in the operating section of the endoscope. has been done. Therefore,
The main body 11 of the first lighting unit 10 is screwed onto the mounting part 3, and the contact plate 15 is attached to the first and second contact pins 1.
7 and 18 and turn on the switch, the lamp 13 provided on the main body 11 lights up.

FIG. 3 shows a second lighting unit 20. FIG. The main body 21 of the second lighting unit 20 is formed to have a larger diameter than the main body 11 of the first lighting unit 10, and this main body 21 is provided with more lamps 13 than the first lighting unit 10. There is.

In such a structure, when the inner diameter of the tube to be inspected is small, the first illumination unit 10 is attached to the mounting part 3, and when it is large, the second illumination unit 20 is attached and inspected. Do this. The first lighting unit 10 and the second lighting unit 20 are
Since the number of lamps 13 provided on these tubes differs, the amount of illumination light irradiating the inner surface of the tube also differs.
Therefore, even if the inner diameter dimensions of the tubes are different, the first lighting unit 10 or the second lighting unit 2
By selecting and using 0, the inner surface of the tube can be illuminated in a good condition. Moreover, if the lamps 13 of each lighting unit 10, 20 are turned on and illumination light is emitted from the light guide 9 at the same time, the illumination condition of the inner surface of the tube can be further improved.

FIG. 4 shows another embodiment of the present invention, in which first and second lighting units 1 are attached to the mounting portion 3.
0 and 20 (the drawing shows the first lighting unit 10) are different in structure. That is, a bayonet pawl 25 is provided on the rear end surface of the main body 11 of the first lighting unit 10, and a bayonet receiver 26 is provided on the stepped portion 16 formed at the base end of the mounting portion 3. It is detachably attached to the attachment part 3 by bayonet connection. Further, although the light guide 9 is not provided in the insertion portion 1 in this embodiment, it may be provided. Naturally, the second lighting unit 20 is also attached to the mounting portion 3 by bayonet connection.

According to such a structure, compared to the case where the first and second lighting units 10 and 20 are screwed to the mounting portion 3, attachment and detachment operations can be performed more easily and quickly.

Note that this invention is not limited to the above embodiments,
For example, by preparing not only two illumination units but three or more illumination units with different amounts of illumination light, the amount of illumination light can be adjusted even better according to the size of the subject. Further, the lamp provided in the illumination unit may be of a so-called circle-line type, a ring-shaped strobe, a fluorescent lamp, etc., and is not limited in this respect at all. Furthermore, the lighting unit may have a built-in power source such as a battery to light the lamp. Further, the imaging optical system may use an image guide made of an optical fiber bundle instead of the solid-state imaging device.

〔Effect of the invention〕

As described above, the present invention includes an insertion section that incorporates an imaging optical system in its distal end, a ring-shaped illumination unit that is removably attached to the outer periphery of the distal end of the insertion section, and a circumference of the ring-shaped illumination unit. It was equipped with a plurality of light sources arranged at equal intervals on the top.

Therefore, by having light sources on the circumference around the imaging optical system, it is possible to uniformly illuminate the area around the subject, and by replacing the illumination unit with one with a different number of light sources, Uniform illumination can be achieved regardless of the size of the subject.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of the distal end of the insertion section showing one embodiment of the present invention, FIG. 2 is a front view of the first illumination unit, and FIG. 3 is a front view of the second illumination unit. FIG. 4 is a sectional view of the distal end of the insertion portion showing another embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Insertion part, 3... Attachment part, 5... Objective lens (imaging optical system), 7... Solid-state image sensor (imaging optical system), 10, 20... Illumination unit.

Claims (1)

[Claims] 1. An insertion section with a built-in imaging optical system in its distal end, a ring-shaped illumination unit that is detachably attached to the outer periphery of the distal end of the insertion section, and an illumination unit provided at equal intervals on the circumference of the ring-shaped illumination unit. An endoscope characterized by comprising a plurality of light sources.