JPH0232890B2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to endoscopes.

In general, an endoscope is equipped with a light guide for guiding and illuminating the subject, and a water/air supply tube for cleaning the objective lens or enlarging the body cavity of the living body to be observed, such as the stomach wall. These light guides, water supply pipes, and air supply pipes are arranged physically independently. The lighting lamp connected to the light transmitting end of the light guide is generally used with a power output of 150 to 250 watts, and since this light is focused onto a bundle of thin optical fibers, the light guide generates a considerable amount of heat. occurs.

The endoscope also has at its tip a solid-state imaging device, such as a charge transfer device (CCD) or a bucket brigade device (BBD), which captures an image of the illuminated subject. There have been problems in that the temperature of such a solid-state image sensor increases due to heat generation, the S/N ratio decreases and failures occur due to dark current, and the life of the solid-state image sensor is shortened.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to solve the above-mentioned problems of conventional endoscopes and to provide a compact endoscope with high cooling efficiency.

According to the present invention, an endoscope is provided with an imaging optical system for capturing an image of a subject on a solid-state image sensor, and an air/water pipe, the air/water pipe being located at the tip of the endoscope. The contact portion of the air/water pipe is arranged so as to be in contact with the back of the solid-state image sensor, and the contact area of the air/water pipe is configured to increase the contact area with the solid-state image sensor, thereby cooling the solid-state image sensor. This is what I decided to do. Therefore, even if the light guide is placed near the solid-state image sensor, there will be no adverse thermal effect on the solid-state image sensor. Therefore, the outer diameter of the endoscope head can be made sufficiently small.
A compact and highly reliable solid-state imaging device endoscope can be provided.

In addition, the present invention uses an air/water supply pipe that is inserted into the endoscope and guided to the distal end for cooling the solid-state image sensor, and then, as necessary, supplies liquid or gas from the distal end to the endoscope. It is an attempt to guide the With this configuration, the air and water supply pipes are used not only for their original purpose but also for cooling the solid-state image sensor, providing a compact and highly reliable endoscope similar to the above-mentioned configuration. can.

The present invention will be explained in detail below with reference to the drawings. In addition,
As used herein, the term "endoscope" includes not only endoscopes used in living organisms, but also industrial endoscopes inserted into internal cavities of devices.

1 and 2 show an embodiment of an endoscope according to the present invention.

In these figures, 1 is an air/water pipe, and around it is a light guide bundle 2 (for example, a diameter of 20 mm).
A fiber bundle of 1,000 to 15,000 optical fibers 3 of ~30 μm is arranged integrally. The light guide bundle 2 is suitably distributed and guided to the endoscope head 5 at suitable locations, for example in the vicinity of the endoscope head 5. That is, as shown in the figure, the optical fibers 3 in the light guide bundle 2 are appropriately distributed and branched into a plurality of light guides 2-1, 2-2, and 2-3, so that the chips of a solid-state imaging device such as a CCD can be connected. 6 is mounted on the package 7, and is connected to the illumination window 9 through the through hole 8 of the package 7. Although the other light guides 2-2 and the like are configured in this manner, illustrations thereof are omitted to avoid complication of the figure.

The air/water supply pipe 1 is separated from the bundle 2 and guided to the back of the package 7 in which the solid-state image sensor 6 is mounted in a meandering manner as shown in FIG. The pipe is branched into two parts, one of which is connected to the return pipe 1a and the other to the small pipe 11. The liquid or gas in the air/water pipe 1 is directed from arrow A and returns to arrow B when the valve 10 is in the normal switching position. When the valve 10 is activated by operation from an operating section (not shown) of the endoscope, it guides fluid or gas from the air/water supply pipe 1 to the small tube 11 . For example, if water is supplied from arrow A, this operation will cause the surface of the window 12 of the imaging optical system to be
The water jetted from the nozzle 13 can be used for cleaning, and when the air is sent from the arrow A, the gas jetted from the nozzle 13 can be used to expand the inner wall of a body cavity such as the stomach. .

Incidentally, the fiber bundle 2 is further provided with a heat insulating layer 14 made of a heat insulating material such as urethane rubber.
covered with. This is to prevent the heat generated from the optical fiber 3 from being conducted to the outside, particularly to the outside of the endoscope, and causing thermal damage or pain to the living body.

This structure in which the fiber bundle 2 and the air/water supply pipe 1 are integrally arranged concentrically when viewed in cross section connects the head 5 of the endoscope and the operating section (not shown). Since the liquid such as water sent from the arrow A to the air/water pipe 1 passes through the connection part 15 and reaches the head 5, It sufficiently absorbs the heat of the fiber bundle 2, further absorbs the heat of the solid-state image sensor 6, and is normally returned in the direction of arrow B through the return pipe 1a. This liquid or gas may be cooled with a cooling device and circulated through the air/water pipe 1 again.

Further, instead of always sending liquid or gas to the air/water pipe 1 as described above, it may be sent only when air/water or cooling of the solid-state image sensor is required. The liquid or gas delivered in this case is expelled through the forceps hole or body cavity.
For example, if the cleaning liquid is sent through the air/water pipe 1,
This cleans the lens system of dirt and cools the solid-state image sensor. Therefore, if the display screen becomes difficult to see, an endoscope operator can use the cleaning solution without having to judge whether the problem is due to thermal noise caused by the temperature rise of the solid-state image sensor or dirt on the lens system. By sending the air through the air/water pipe 1, the solid-state image sensor can be cooled, the lens system can be cleaned, and the display screen can be improved, so the operation is easy.

As is clear from the above description, according to the present invention, since the solid-state imaging device is directly cooled using a liquid such as a cleaning liquid for the imaging window or a gas for expanding the body cavity wall, the cooling efficiency is high. It is possible to eliminate the adverse effect on imaging due to temperature rise of the solid-state image sensor. Furthermore, since the air and water supply pipes are used as cooling pipes, an increase in the thickness of the endoscope can be prevented.

[Brief explanation of drawings]

FIG. 1 is a side sectional view showing an embodiment of an endoscope according to the present invention, and FIG. 2 is a partially omitted rear view of the endoscope shown in FIG. Explanation of symbols of main parts, 1...Air/water pipes,
2...Light guide bundle, 6...Solid image sensor chip, 10...Bulb.

Claims (1)

[Scope of Claims] 1. A solid-state imaging device disposed at the distal end to capture an image of the subject, an imaging optical system for projecting the image of the subject onto the solid-state imaging device, and In an endoscope equipped with an air/water pipe for sending gas and liquid, the air/water pipe is arranged so as to be in contact with the back of the solid-state image sensor disposed at the tip of the endoscope. , the contact part of the air/water pipe is,
An endoscope characterized in that the endoscope is configured to have a large contact area with the solid-state image sensor, thereby cooling the solid-state image sensor. 2. In the endoscope according to claim 1, the tip of the air/water pipe passing through the back of the solid-state image sensor is guided outside the endoscope to supply air/water. An endoscope characterized by: 3. In the endoscope according to claim 2, the air/water supply pipe that has passed through the back of the solid-state image sensor is divided into two pipes, one of which is guided outside the endoscope, and the other is guided inside the endoscope. What is claimed is: 1. An endoscope, which is inserted into the endoscope, and is configured to control diversion by means of a valve means.