JPS5846924A - Endoscope - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an endoscope, and particularly to an endoscope that uses a solid-state image pickup device to extract an image of a subject as an electrical signal and guide it to an image display device such as a cathode ray tube to reproduce the image. .

Endoscopes that use solid-state imaging devices, such as charge transfer devices (CCDs), packet 1srs, and dove vices (BBDs), are more economical than conventional endoscopes that use optical fibers as image guides. It is viewed as promising because of its small size and many other advantages.

However, from the standpoint of miniaturization, this type of conventional endoscope cannot be said to leave room for structural improvement.

For example, when inserting an endoscope head into the stomach, it is desirable to make the endoscope head as small as possible in order to eliminate pain for the patient. It was not satisfying.

In direct-view endoscopes using conventional solid-state imaging devices, the imaging surface on which the pixels of the solid-state imaging device are arranged is arranged perpendicular to the longitudinal direction of the sheath of the endoscope head, and one or more The light guide, water supply/air supply holes, forceps/treatment tool guides, etc. pass through the side of the cage of the solid-state image sensor and extend to the front end surface of the sheath. Since the size of the solid-state image pickup device itself is relatively large compared to its effective image pickup surface, in a structure in which a light guide or the like passes outside the sheath, the outer diameter of the sheath is small. An object of the present invention is to provide an endoscope using a solid-state imaging device having a small head.

According to the invention, this object is achieved by an endoscope as follows. In other words, this endoscope includes a sheath that is generally cylindrical as a whole, an imaging optical system whose optical axis is arranged substantially parallel to the longitudinal direction of the sheath, and an imaging surface that is substantially perpendicular to the optical axis. The solid-state image sensor has a generally cylindrical cage supported inside the sheath, and the periphery of the cage extends from one end surface to the other end surface. The light guide is provided with an opening communicating with the sheath through which the light guide terminates at the end surface of the sheath.

With this configuration, the endoscope according to the present invention has at least the light guide incorporated into the /4' position of the solid-state image sensor and arranged close to each other in the longitudinal direction of the sheath.
This not only reduces the diameter of the endoscope head, but also has the effect of uniformly illuminating the subject using the light guide.

According to an aspect of the present invention, a plurality of such openings may be arranged, and the light guide may be passed through at least two of these openings. As a result, the diameter of each light guide required to maintain a constant illuminance of the subject can be made smaller, making it possible to further reduce the head-to-outer diameter and making uniform illumination of the subject even more effective. Furthermore, throughout this specification, "
The term "opening" is used to include not only those whose cross-sectional shape is completely closed, but also those whose cross-sectional shape is open, that is, notches. will be shown and explained in detail. Note that in this specification, the term "endoscope" includes not only an endoscope inserted into a body cavity of a living body, but also an endoscope used for industrial use inserted into a cavity of an apparatus. , , FIG. 1 is a side cross-sectional view showing the configuration of the main parts of the endoscope head according to the present invention. In FIG. They are arranged to form an imaging surface, and are supported by a support 4 made of, for example, ceramic.・A sheath part 8 is attached to the periphery of the Yutsugaji 4 as shown in the figure.
A plurality of small holes 5 and notches 5a are provided in parallel in the longitudinal direction of the holder, and a light guide 6 consisting of a large number of onotic fibers and an air/water supply pipe are provided in these small holes 5 and notches 5a. The tips of the 0 light guides 6, through which the numbers 7 and 7 pass, are connected to glass windows 9 provided in the front part of the sheath 8.
The light guided by the light guide 6 is irradiated onto the object (not shown), and the objective lens, 1G
The image of the subject is focused on three pixel surfaces of the solid-state image sensor through the glass window 11, and the electrical signals obtained from this element corresponding to the light of the image point are transmitted through the conductor 12 to an image display device such as a cathode ray tube ( IfC (not shown) is used to reproduce the image of the subject and enable observation.

FIG. 2 is a cross-sectional view taken along the line mA-A in FIG. 1, and the present invention will become clearer by referring to FIG. In FIG. 2, the same reference numerals as in FIG. 1 refer to the same elements as in FIG. - Sheath part 8 is Zorasti.

The endoscope is preferably made of metal coated with resin, rubber, or the like, and the shape of the endoscope is preferably approximately cylindrical as a whole from the viewpoint of ease of insertion into the body cavity of the endoscope head.

The shape of the openable package 4 is also flat and approximately cylindrical as a whole in accordance with the sheath portion 8.The shape of the opening package 4 is also flat and approximately cylindrical as a whole in the present invention. - It is advantageous in terms of space efficiency. That is, it is possible to relatively increase the effective area of the image pickup device compared to the conventional rectangular e-couge.

As shown in FIG. 2, in the embodiment of the endoscope according to the present invention, a plurality of light guides 6 are housed in a distributed manner around the periphery of the cylindrical lock cage 4. As shown in FIG.

Therefore, only one of the plurality of light guides 6, which are branched almost equally from a large number of onotic fibers included in the light guide bundle 13, passes through the small hole 6, and the other light guide rods are not shown on the way. However, as can be seen from FIG. By providing multiple light guides 6 and dispersing them around the cage 40 in this way, the light from each light guide 6 is focused on the subject to illuminate the salmon. As a result, uniform illumination can be achieved.This will be described in more detail with reference to FIG.

FIG. 3 is an enlarged view of the glass window 90 portion in FIG. 1. As is clear from FIG. 3, the structure of the glass window 9 and the attachment of the light guide 6 to the glass window 9 are shaped so as to provide directivity of light from the light guide 6. That is, the inner surface 91 of the window 9 is inclined as shown in the figure, so that the light emitted from the light guide 6 glued perpendicularly to this surface with a suitable transparent adhesive is directed in the direction of the arrow 15 in the figure. being done. , this direction is the objective lens lO
The other light guides 6 are connected to the corresponding windows 9 in the same way, so that the illumination light exiting each light guide 6 is directed to a certain point on the optical axis of the objective lens 100. , that is, they intersect near the focal point of the objective lens 10. Therefore, the object to be examined near the optical axis is illuminated more effectively and uniformly by condensing the illumination light from the plurality of light guides 6.

Returning again to FIGS. 1 and 2, the explanation will be continued. In the embodiment, a notch 5a for the air/water pipe 7 is provided at the periphery of the motherboard 40, and the air/water pipe is inserted therein. 7 is shown, but this only shows that such a construction is possible if necessary, and other elements such as forceps or treatment instruments can be added as necessary. The guide path may be housed in these small holes 6 or notches 5a provided in the nokutsuzo 4. In this embodiment, the air/water supply pipe 7 is located near the center of the light guide bundle 13, and the surrounding area is A plurality of optical fibers are surrounded concentrically by optical fibers, and a plurality of optical fibers are branched almost equally at the end of the bundle 13 to form a plurality of light guides 6.

This is to prevent the light guide 6 from overheating and causing thermal damage to the solid-state image sensor 1 located near the light guide 6, since illumination of the object by the light guide 6 generates a small amount of heat. Therefore, the onotic fibers passing through the bundle 13 are cooled by liquid or gas passing through the water/air pipe 7.

Furthermore, according to which technology, even if the currently used large illumination light beam shaker is used, it will not cause heat damage or pain to the living body being examined. However, other variations are also possible. For example, the number of light guides 6 does not necessarily have to be plural, and may be one. In the above embodiment, i4
Although the small hole 5 for the light guide 6 was provided in the y-cage 4, a cutout similar to the cutout 5m may be provided instead. Furthermore, other variations are possible without departing from the spirit of the invention.゛By having the endoscope according to the present invention configured as described above, the body of the solid-state image sensor can be used as a light guide, a water supply/air supply pipe,
And/or the forceps, treatment instrument conduit, etc. pass through, so the endoscope head can be made smaller. Furthermore, since the light guide is arranged close to the optical axis of the imaging system, the subject can be uniformly illuminated, and this is even more effective in embodiments in which a plurality of light guides are distributed.

[Brief explanation of the drawing]

FIG. 1 is a side cross-sectional view showing the main structure of an endoscope head according to the present invention, FIG. 2 is a cross-sectional view taken along the dashed line A-A in FIG. 1, and FIG. 3 is a cross-sectional view of the glass window in FIG. 1. Explanation of the symbols of the main parts, which are enlarged views of the parts.Solid-state image sensor... 1 Nogutsu cage... 4 Aperture... 5 + 5
a Light guide...6

Claims (1)

[Claims] 1. A sheath portion having a generally cylindrical shape as a whole, an imaging optical system having an optical axis disposed substantially parallel to the longitudinal direction of the sheath portion, and an imaging surface substantially aligned with one optical axis. and a solid-state image sensor disposed perpendicularly to the sheath, the solid-state image sensor having a substantially cylindrical overall shape supported inside the sheath, and the solid-state image sensor having a substantially cylindrical shape as a whole, An endoscope characterized in that the peripheral portion has an opening that communicates from one end surface of the nook cage to the other end surface, and the endoscope includes a light guide that passes through the opening and terminates at the end surface of the sheath portion. 2. The endoscope according to claim 1, wherein a plurality of the openings are provided, and a light guide passes through each of at least two of the plurality of openings. endoscope. 3. In the endoscope according to claim 1 or 2, the light guide terminates at the end surface of the sheath so that the light exiting the light guide approaches the optical axis of the imaging optical system. An endoscope that is characterized by: 4. In the endoscope according to claim 1 or 2, the light guide conducts optical fibers that are almost equally branched from a single light guide bundle that includes a large number of optical fibers. Endoscope 0 characterized by