JPH0213283B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a solid-state imaging device-integrated endoscope that incorporates a solid-state imaging device together with its drive circuit and the like.

Over the past few years, efforts have been made to improve the bendability and durability of the insertion section in endoscopes, which are constructed by connecting the insertion section, which consists of a so-called flexible section, a curved section, and a distal end, etc., to a manual operation section. In order to economically obtain clear images of observation and inspection areas, we have developed an electrical method using a solid-state image sensor and its drive circuit, instead of the conventional image guide using an optical fiber bundle. Studies have been conducted on the applicable technology.

By the way, in this type of endoscope that is currently being put into practical use, the solid-state image sensor and part of its drive circuit are housed inside the distal end section, which is also called a rigid distal section for the endoscope structure. Therefore, the length of the distal end in the axial direction, that is, along the length of the insertion part, is inevitably long, which significantly impedes the ease of bending in narrow areas such as inside the body cavity. There were some drawbacks, and this was one of the major practical obstacles.

In view of the above-mentioned difficulty, which is one of the major practical difficulties in endoscopes with built-in solid-state image sensors, the present invention has been developed to provide a photographing optical system mounted in the distal end of the endoscope. The solid-state image sensing device is fixed at the focal position of the image sensor, and its drive circuit, output amplification circuit, and other circuit units are distributed and supported in different node rings for forming the curved portion. By connecting each circuit unit with a twisted thin flexible printed wiring board, we first shortened the tip, which is the rigid area for forming the insertion part of the endoscope, and then increased the resistance to bending. This makes it possible to provide an endoscope incorporating a solid-state image pickup device that has uniformity and excellent bending operability. This will be explained in detail below.

In the figure, 1 is a curved section also called a curved tube or curved tube section, and this seems to be part of a component called a so-called flexible section, flexible tube, flexible tube section, etc. Reference numeral 10 denotes a distal end section, which is sometimes referred to as a rigid distal section, and is used to constitute a so-called insertion section in an endoscope.

The curved portion 1 is formed into a tubular shape by a flexible outer skin tube 2 made including a mesh pipe, and a number of joint rings 3 used for regulating the bending direction. The fact that several operating wires 4 used for bending, a light guide formed of an optical fiber bundle, etc., an air and water pipe, a forceps channel 5 for inserting and guiding the forceps 40, etc. are built-in and protected.
As before, in the present invention, each adjacent node ring 3, every other node ring, or every several nodes among the plurality of node rings 3 is selected as appropriate, and the tips described below are A drive circuit 22 for the solid-state image sensor 21 mounted on the unit 10, an amplifier 23 for amplifying the output of the solid-state image sensor 21, and an A/D conversion circuit 2.
4. Each circuit unit such as an electric-to-optical converter 25 to which a light guide 30 for optical communication is connected is supported.

In addition, in the tip section 10, 11 is an outer shell for forming the tip section, which is also referred to as tip metal fittings, etc., 12 is the end thereof, and 13 is the rearward part from the end section 12. The rear part extends in a cylindrical shape, and 14 is a lens barrel attachment hole bored from the end face of the end part 12, and 15 is a photographing optical system 16, which usually consists of several lenses, inside. A fixed lens barrel 17 is connected to the photographing optical system 16,
It is a window with a lens provided with a lens 18 which is also a component thereof. In addition, an illumination window, an air/water supply port, an outlet for the forceps 40, and the like are formed in the end portion 12 in the same manner as in the previous ones.

Further, inside the rear part 13, a photographing optical system including the lens 18 is fixed to a sheath body 20 which surrounds the rear opening of the lens barrel mounting hole 14 at one opening end, At the focal point of system 16,
A solid-state image sensor 21 such as a CCD or a MOS image sensor is fixed.

Between the solid-state image sensor 21 and its drive circuit 22, there is an amplifier 23 between the solid-state image sensor 21 and an output amplification circuit or an output amplifier.
3 and A/D conversion circuit 24, A/D converter etc.
Between the D conversion circuit 24 and the electric-optical converter 25, etc.,
Depending on the interval, twist the curved part 1 by about 90 degrees.
Flexible printed wiring thin plates 26, 27, 2 with uniform resistance when bending
8,29 are connected. However, some of the wiring on the flexible printed wiring thin board 27 utilizes the flexible printed wiring thin board 26.

As is clear from the above description, in the present invention, as in the conventional technology applied to endoscopes of this type, each circuit unit such as a drive circuit, an output amplification circuit, etc. is installed in the tip part along with a solid-state image sensor. Because these are distributively arranged and supported on the separate joint rings for the cylindrical pipe structure of the curved part that continues from the tip, without having to incorporate them, the tip can be narrowed without increasing the size and length of the tip. The thin flexible printed wiring board, which not only improves the operability in the area, but also connects the circuit units distributed and supported in each node ring, is not a flat thin plate, but also has a flexible printed wiring board that connects the circuit units distributed and supported in each node ring. Since it was twisted according to the interval of
Since the resistance to curving is uniform regardless of the direction of curvature of the curving portion, the present invention has a structure that allows the tip to be shortened and the curving operation to be carried out smoothly. This makes it possible to provide an endoscope with a built-in solid-state image sensor that does not cause erroneous operation.

[Brief explanation of drawings]

In order to explain the main structure of an embodiment of the solid-state imaging device-integrated endoscope according to the present invention, the drawings are partially cut away or shown vertically, and components other than the main structure are omitted. It is a diagram for explaining the main part configuration. 1; Curved part, 2; Outer tube, 3; Nodal ring, 4; Operation wire, 5; Forceps channel, 10; Tip part, 11; Tip body, 12; End part, 13; Posterior part, 14; Mirror Body mounting hole, 15; Lens barrel, 16; Photographing optical system, 17; Window with lens, 18; Lens, 2
0; sheath body, 21; solid-state image sensor, 22; drive circuit, 23; amplifier, 24; A/D conversion circuit, 2
5; Electrical-optical converter, 26, 27, 28, 29;
Flexible printed wiring thin board, 30; Light guide for optical communication, 40; Forceps.

Claims (1)

[Claims] 1. A solid-state image sensor is fixed at the focal position of a photographing optical system attached to the tip, and each circuit unit such as a drive circuit, an output amplification circuit, etc. is connected to a curved portion for each circuit unit. A solid-state image sensing element built-in type interior characterized in that the circuit units are supported in a distributed arrangement on separate joint rings for formation, and the circuit units are connected by flexible printed wiring thin plates twisted according to the spacing between them. Endoscope. 2. The endoscope incorporating a solid-state image sensor according to claim 1, wherein the solid-state image sensor is a so-called CCD or MOS image sensor. 3 The output amplification circuit of the solid-state image sensor is an amplifier and an A/
An endoscope incorporating a solid-state image sensor according to claim 1, characterized in that it is a D-conversion circuit unit or the like. 4. Claim 1, characterized in that each circuit unit of the solid-state image pickup device drive circuit and output amplification circuit is supported by a joint ring with one or several joint rings placed between them. The solid-state imaging device built-in endoscope described above.