JP2818154B2 - Endoscope tip structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an endoscope, and more particularly, to a distal end structure of an endoscope using a solid-state image sensor instead of an image fiber.

[0002]

2. Description of the Related Art In a conventional endoscope, a subject image is formed by an objective lens provided at the tip of a portion inserted into the body, and the image is guided to an eyepiece through an image fiber for observation. Met. However, recently, with the development of solid-state imaging devices, it has been attempted to form an observation image by an objective lens on the solid-state imaging device and to project an observation image on a television screen by a signal from the solid-state imaging device. An endoscope using this solid-state imaging device may use a signal line instead of an expensive image fiber, and since the observation does not need to be performed through an eyepiece, the operator has
It can be operated in a natural posture while watching the TV screen, and has excellent operability. In addition, the resolution is improved compared to the so-called external TV camera attached to the eyepiece of the endoscope,
In addition, since it is possible to electrically process image signals, there is a feature that observation performance and diagnostic performance are excellent.

A solid-state image pickup device such as CMOS, CCD, CPD, etc. is, for example, provided on the surface of a silicon single crystal thin plate (wafer).
A silicon oxide film is formed, and a photolithography method is further formed on top of this.
A required integrated circuit pattern is formed by using techniques such as thermal diffusion and vapor deposition. A silicon oxide film, an aluminum film, and the like are exposed on the surface of the integrated circuit pattern, and these are very easily oxidized and corroded. For this reason, the surface is covered with a front glass, and the space between the device and the element is sealed with an inert gas such as nitrogen gas. The front glass also has a role of preventing dust from adhering to the element surface, which is an image forming surface, and preventing dust from forming an image. That is, even if the dust adheres to the front glass surface, the dust is out of focus and is not observed as dust.

[0004] However, since the front glass has a certain thickness, there is a problem that a space is required for the objective optical system of the endoscope. That is, the insertion part of the endoscope in the body is required to be as thin as possible, and to shorten the rigid part at the tip in order to reduce the pain of the patient. If it is thicker, it cannot be used as a stomach endoscope. Under such demands, the solid-state image pickup device with a front glass filled with an inert gas itself becomes thicker, which deteriorates the space efficiency. That is, for example, the diameter and length of the rigid portion at the distal end of the body insertion portion are increased, and the storage space for other internal components is sacrificed, so that the functions of the endoscope such as light intensity and biopsy ability are reduced.

In addition, if other built-in components such as a forceps channel for inserting a biopsy tool, a light guide for illumination, and the like are mainly configured, a good arrangement of the objective optical system and the solid-state imaging device cannot be obtained. Further, the solid-state imaging device has an input terminal for inputting an electric drive signal for imaging, and an output terminal for outputting an image signal converted into an electric signal by imaging. Therefore, a space for accommodating these input / output terminals and signal lines connected to these input / output terminals is required.

[0006]

SUMMARY OF THE INVENTION The present invention pays attention to such a problem of an endoscope using a conventional solid-state image pickup device, and can effectively utilize the space at the distal end of the body insertion portion or save the space. It is an object of the present invention to provide a distal end structure of an endoscope.

According to the present invention, there is provided an elongated body extending to a distal end portion of a body insertion portion, an objective lens, and a solid-state imaging device having an element surface located on an image forming surface of the objective lens at the distal end portion. An endoscope comprising: the solid-state imaging device, the solid-state imaging device having two rows of input / output terminals formed in a plate shape along opposing edges of the device surface and extending in a direction opposite to the device surface; The solid-state imaging device is arranged close to the elongated body so that the input terminals are located on both outer surfaces of the elongated body. It is characterized by being arranged close to the above-mentioned elongated body in such a form.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the illustrated embodiments. 1 and 2 show a first embodiment of the present invention, in which the present invention is applied to a side-view type endoscope. A cover glass 12 of the objective optical system and a cover glass 13 of the illumination optical system are arranged on the side of the rigid portion 11 at the tip of the body insertion portion. Cover glass 12
A first right-angle prism 14 is adhered to an inner surface of the right-angle prism 14, and an objective lens 15 having an optical axis in an axial direction of a body-inserted portion is located on an optical path of the right-angle prism 14.

A second right-angle prism 16 is further positioned on the optical path of the objective lens 15. One surface of the right-angle prism 16, that is, a surface 16 a parallel to the axial direction of the insertion portion of the rigid portion 11 in the body. Element surface 20 of solid-state imaging device 20
a is directly bonded via an optical adhesive. The right-angle prism 16 has its slope 16 b adhered to a prism holder 17, and the prism holder 17 is fixed to the rigid portion 11 via a fixing screw 18.

FIG. 3 shows an element surface 20a of the solid-state image sensor 20.
This schematically shows the state of adhesion between the right-angle prism 16 and the right-angle prism 16. The right-angle prism 16 is directly bonded to the element surface 20 a via an optical adhesive 19. Of course, the element surface 20a
May be provided with a suitable protective film other than the optical adhesive 19. Although the adhesive 19 is filled between the prism 16 and the element surface 20a in FIG.
0a may be in close contact.

As described above, the element surface 2 of the solid-state imaging device 20
If Oa is directly bonded to the right-angle prism 16 without passing through the front glass, a space is created in the hard portion 11. The element surface 20a is protected by the right-angle prism 16 and the optical adhesive, and does not come into contact with the outside air. Therefore, the element surface 20a is not oxidized or corroded. In particular, corrosive gases such as formalin gas and ethylene oxide gas are used for disinfecting endoscopes, but oxidation can be prevented even for these disinfecting gases.

As is apparent from FIGS. 1 and 2, the solid-state image pickup device 20 has a thin rectangular parallelepiped shape having a large surface having an element surface 20a, and a flat plate along the opposing edge of the element surface 20a. And two rows of input / output terminals 20b and 20c extending in a direction opposite to the element surface 20a.
As is well known, the input / output terminals 20b and 20c are used as electric terminals for reading out a driving signal for imaging and an imaged image signal. And the solid-state imaging device 2
0 is the input / output terminal 20b, as is apparent from FIGS.
Input / output terminals 2 such that the light guide 21
Ob and 20c are arranged on both sides of the light guide 21 in the radial direction. With such an arrangement, the input / output terminals 20
Since the signal lines 22 and 22 connected to the b and 20c extend along the outer surface while holding the light guide 21 from both outer surfaces, the space on both sides of the light guide 21 can be effectively used. . The present invention can be applied to a case where the prism 16 is not directly adhered to the element surface 20a of the solid-state imaging device 20, that is, a case where a conventional solid-state imaging device in which a front glass is covered on the element surface 20a is used.

As is well known, the light guide 21 guides illumination light from a light source device outside the endoscope to the cover glass 13 to illuminate the subject. The other illustrated components will be described.
The various treatment tools and forceps inserted from the operation unit are connected to the rigid unit 1.
The air supply port 25 and the water supply port 26 for guiding and protruding to the tip of 1 are for sending or sucking a cleaning liquid, air, or the like for removing dirt on the surfaces of the cover glasses 12 and 13. .

FIGS. 4 and 5 show an embodiment in which the present invention is applied to a direct-viewing type endoscope. In this embodiment, the cover glass 12 is provided at the tip of the hard portion 11 and the right-angle prism 1 is provided.
4 is omitted, and the relationship between the right-angle prism 16 and the solid-state imaging device 20 is the same as in the first embodiment. That is, the element surface 20a is directly bonded to the right-angle prism 16 without passing through a front glass for sealing an inert gas.

In this embodiment, it is desirable to use a roof prism as the right-angle prism 16 or to electrically invert the left and right of the output signal of the solid-state imaging device 20 in order to prevent the left and right inversion of the observed image.

In this embodiment, the solid-state imaging device 2
The forceps channel 24 is disposed between the input / output terminals 20b and 20c of the first input / output terminal 20 so that the signal lines 22, 22 connected to the input / output terminals 20b and 20c hold the forceps channel 24 from both outer surfaces. In addition, it is arranged along the outer surface of the forceps channel 24. The light guide 21, the air supply port 25, and the water supply port 26 are arranged in the rigid portion 11, for example, as shown in FIG.

[0017]

As described above, according to the present invention, the objective lens and the solid-state image pickup device located on the image forming surface of the objective lens are arranged at the distal end of the body insertion portion of the endoscope. Since the input / output terminals of the endoscope are located on both sides of a long body, for example, a light guide, a forceps channel, etc. to be disposed in the body insertion portion, the space at the distal end of the endoscope can be effectively used. It is possible to improve the performance of the endoscope by increasing the possibility of storing the built-in object.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a main part showing an embodiment of an endoscope of the present invention.

FIG. 2 is a sectional view taken along the line II-II in FIG.

FIG. 3 is a schematic diagram showing an adhesion state between an element surface of a solid-state imaging element and a prism.

FIG. 4 is an optical system diagram showing another embodiment of the present invention.

5 is a cross-sectional view corresponding to FIG. 2, showing an example of the arrangement of another built-in component in the embodiment of FIG. 4; DESCRIPTION OF SYMBOLS 11 Hard part (tip of body insertion part) 12 13 Cover glass 15 Objective lens 16 Right angle prism 19 Optical adhesive 20 Solid-state image sensor 20a Element surface 20b 20c Input / output terminal 21 Light guide 22 Signal line 24 Forceps channel

Claims (3)

(57) [Claims] An elongated body extending to a distal end of an insertion portion in a body is provided with an objective lens and a solid-state imaging device having an element surface located on an image forming surface of the objective lens. An endoscope, wherein the solid-state imaging device includes two rows of input / output terminals formed in a plate shape along opposing edges of the device surface and extending in a direction opposite to the device surface. The element is arranged close to the elongated body so that the input terminals are located on both outer surfaces of the elongated body, and the objective lens has a form in which an imaging surface coincides with an element surface of the solid-state imaging device. 3. The end structure of an endoscope, wherein the end structure is disposed close to the elongated body. 2. The device according to claim 1, wherein the elongated body is a light guide or a forceps channel, and a signal line connected to the input / output terminal is arranged along an outer surface of the light guide or the forceps channel. The distal end structure of the endoscope according to claim 1. 3. The end of the endoscope according to claim 1, wherein the solid-state imaging device is fixed to a prism that bends light from the objective lens toward the solid-state imaging device. Part structure.