JPH04335611A - Fitting structure for solid-state image pickup device for electronic endoscope - Google Patents

Abstract

PURPOSE:To arrange an observation window at the center position of the endoscope of an electronic endoscope device without increasing the endoscope diameter. CONSTITUTION:In the fitting structure for fitting the CCD 17 connected to an optical system to a circuit board at the tip part of the electronic endoscope 1, an optical system such as the observation window 3 and an objective 5 is arranged nearby the center axis of the endoscope and a CCD 17, a package 18, and a flexible substrate 20 are arranged in the direction of an endoscope barrel; and the CCD 17 and circuit board are connected by wire bonding at 19 and 21 in the axial direction and the wire bonding parts 19 and 21 and a mold 22 covering the wire bonding parts are formed within the thickness of cover glass 8 provided halfway between the optical system and CCD 17.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure for mounting a solid-state image sensor for an electronic endoscope, and more particularly to a structure for mounting a solid-state image sensor inside an electronic endoscope inserted into a subject.

0002

[Prior Art] An electronic endoscope device inserts an electronic endoscope, which is a scope, into a body cavity or cavity to display an image of the inside of the body on a monitor. A solid-state image sensor, such as a CCD (C
This is done by providing a harge coupled device). FIG. 2 shows the structure of the tip end of this type of electronic endoscope. As shown in FIG. Windows 2a, 2b, an observation window 3, a forceps port 4, etc. are provided. Further, as shown in Figure (b), an objective lens 5 is provided inside the observation window 3, and a treatment instrument insertion channel 6 is formed inside the electronic endoscope 1 in communication with the forceps port 4. By inserting forceps or the like into this treatment instrument insertion channel 6, tissue within the body cavity can be collected.

At the rear stage of the objective lens 5 disposed in the observation window 3, there is a C.
A CD 10 is provided, and when light is irradiated into the object to be observed from the irradiation windows 2a and 2b, an image of the inside of the object to be observed captured by the objective lens 5 is captured by the CCD 10. This CCD 10 is connected to a circuit board 12 via a package 11, and a signal cable 13 is connected to this circuit board 12. That is, as shown in FIG. 4, a CCD is connected to the prism 7 through a cover glass 8.
This CCD 10 is attached to a ceramic package 11 with a bonding wire 14, and this package 11 connects the CCD
10 is protected from environmental conditions. Further, this package 11 is attached to a circuit board 12 made of a rigid board with thick bonding wires 15, and a mold 16 is formed to cover the bonding portion.

According to the above structure, the image of the object to be observed that has entered the objective lens 5 is supplied to the imaging surface of the CCD 10 by the prism 7, and the video signal obtained by this CCD 10 is transmitted onto the circuit board 12. The signal is supplied into the main processing device via a signal cable 13 through a circuit formed in the .

[0005]

[Problems to be Solved by the Invention] However, in the conventional mounting structure for the solid-state image sensor, the CCD
10 and the circuit board 12 including the package 11 is arranged at the center of the shaft, so the observation window 3 is arranged at a position slightly offset from the center of the endoscope, as shown in FIG. 3 above. There was a problem. That is, the operator performs operations such as positioning, moving, and inserting the endoscope while viewing the image obtained by the endoscope. However, if the observation window 3 is not located at the center of the endoscope, , it is difficult to establish a correspondence between the observation viewpoint and the center of the endoscope, making it impossible to position or move the endoscope to the desired position. Therefore, in the past, there was a problem in that sufficient operability could not be obtained because the operator had to rely on the experience and intuition of the operator.

[0006] Therefore, it is conceivable to arrange the CCD 10, circuit board 12, etc. near the endoscope barrel. but,
As shown in FIG. 4, the bonding wires 14 of the CCD 10 and the package 11 and the bonding wires 15 of the package 11 and the circuit board 12 are connected in the radial direction of the electronic endoscope. The width of the circuit board 12 in the radial direction becomes wider. With electronic endoscopes,
In order to make it possible to insert it into a narrow body cavity, it is necessary to make the diameter of the endoscope small to a certain extent. There is a problem that it cannot be arranged in the cylindrical direction.

The present invention has been made in view of the above-mentioned problems, and its purpose is to reduce the diameter of the endoscope without increasing the diameter of the endoscope.
An object of the present invention is to provide a mounting structure for a solid-state image pickup device for an electronic endoscope, which allows an observation window to be placed at a central position within the endoscope.

[0008]

[Means for Solving the Problems] In order to achieve the above object, the present invention connects a solid-state image sensor to an optical system disposed at the tip of an electronic endoscope, and connects the solid-state image sensor to a circuit board. In the mounting structure of the solid-state image sensor for mounting,
The optical system is arranged near the central axis of the endoscope, while the solid-state image sensor and circuit board are arranged in the direction of the endoscope barrel, and the solid-state image sensor and the circuit board are connected in the axial direction by wire bonding. In addition, the present invention is characterized in that the wire bonding and the mold covering the wire bonding portion are formed within the thickness of the cover glass disposed between the solid-state image sensor and the optical system.

[0009]

[Operation] According to the above configuration, since the wire bonding is formed in the axial direction, the width of the circuit board in the radial direction of the endoscope can be reduced to the width of the solid-state image sensor.
In addition, since the bonding wire and mold do not exceed the height of the cover glass, the circuit board containing the solid-state image sensor can be stored well inside the electronic endoscope, and the endoscope diameter does not become large. .

0010

[Embodiment] FIG. 1 shows a mounting structure for a solid-state image pickup device for an electronic endoscope according to an embodiment, and as shown in FIG. , 2b, an observation window 3, and a forceps opening 4 are arranged. As shown in Figure (a), a prism 7 is attached to the rear side of the observation window 3 via an objective lens 5, and a CCD 17 is disposed on this prism 7 via a cover glass 8. As shown in the figure, the observation window 3 is disposed closer to the central axis 100 of the endoscope than in the past, and the CCD 17 is arranged in the cylindrical direction of the cover glass 8.
Therefore, the position of the prism 7 is also placed in the opposite direction from the conventional one. In addition, as shown in the detailed view of FIG. 2, the CCD 17 includes a
A ceramic package 18 (
This is also a type of circuit board). In the embodiment, a storage groove 18a is formed in the package 18,
The CCD 17 is embedded in this storage groove 18a, thereby reducing the overall thickness of the circuit board to which the CCD 17 is attached.

[0011]The above CCD 17 and package 18
are connected with a bonding wire 19 in the axial direction of the endoscope, and the package 18 is connected with a bonding wire 21 at a predetermined position of the flexible substrate 20 in the axial direction of the endoscope. Therefore, as shown in FIG. 2(a), the width d of the package 18 to which the CCD 17 is attached and the flexible substrate 20 can be made smaller by the bonding wire connection portion than in the past. Here, as shown in FIG. 2(b), the bonding wire 19
, 21 are formed to fit within the thickness of the cover glass 8, and in the embodiment, the wires are bonded to such an extent that the gap t shown in the figure is created, and the mold 22 of the bonding wires 19, 21 is also formed within the thickness of the cover glass 8. Shape it to fit inside. According to this, the package 18 and the flexible substrate 20 can be positioned in a good condition near the tube inside the endoscope. On the other hand, prism 7
Even if the holding member of the objective lens 5 protrudes into the cover glass 8, the arrangement of the circuit board can be maintained without changing.
Furthermore, the circuit board including the CCD 17 can be placed near the endoscope barrel without ensuring a radial distance.

Further, the flexible substrate 20 of the embodiment is bent at its rear end toward the prism 7 in the middle, and the signal cable 13 is connected to the bent portion. Therefore, the signal cable 13 is attached to the side opposite to the conventional one, and other circuit elements 25 such as transistors are also attached to the prism 7 side of the bent portion.

According to the configuration of the above-described embodiment, as shown in FIG. 3(c), the observation window 3 is located closer to the endoscope central axis 100 than the conventional structure shown in FIG. Therefore, the operator's observation viewpoint and the central axis of the endoscope almost coincide. Therefore, an electronic endoscope with good operability is obtained, and it becomes possible to easily move and position the tip of the endoscope to a desired position without relying on experience.

[0014]

[Effects of the Invention] As explained above, according to the present invention,
The optical system including the observation window is arranged near the central axis of the endoscope,
On the other hand, a solid-state image sensor and a circuit board are arranged in the direction of the endoscope barrel, and the solid-state image sensor and the circuit board are connected in the axial direction by wire bonding, and the wire bonding and the mold covering the wire bonding part are attached to the cover glass. Since the thickness of the circuit board is within the thickness of , it is possible to reduce the radial width of the circuit board including the package and to arrange the circuit board near the endoscope barrel. Therefore, it is possible to arrange the optical system, that is, the observation window, on the central axis of the endoscope, and it is possible to obtain an electronic endoscope with good operability. The advantage is that the tip of the endoscope can be easily positioned and moved.

[Brief explanation of the drawing]

FIG. 1 is a partial cross-sectional view showing the mounting structure of a solid-state image sensor for an electronic endoscope according to an embodiment of the present invention, and FIG. b) is a diagram showing the upper part of the endoscope in Figure (a) exposed, and Figure (c) is a diagram of the end surface of the endoscope.

FIG. 2 is a detailed view of the connection state between the optical system of the example and the circuit board including the CCD, where FIG. 2(a) is a perspective view of the connection portion, and FIG. .

FIG. 3 is a diagram showing the configuration of a conventional electronic endoscope tip;
Figure (a) is a front view of the tip, and Figure (b) is a partial cross-sectional view of the inside of the hard tip.

FIG. 4 is a detailed diagram of a connection state between the optical system of FIG. 3 and a circuit board including a CCD.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1... Electronic endoscope, 3... Observation window, 7... Prism, 8... Cover glass, 10, 17... CCD, 11, 18... Package, 12... Circuit board, 14, 15, 19, 21... Bonding wire, 16 , 22...mold, 20...flexible substrate.

Claims (1)

[Claims] Claim 1: A solid-state image sensor mounting structure for connecting a solid-state image sensor to an optical system disposed at the distal end of an electronic endoscope and attaching the solid-state image sensor to a circuit board, wherein the optical system is installed inside the solid-state image sensor. The solid-state image sensor and the circuit board are arranged near the central axis of the endoscope, and the solid-state image sensor and the circuit board are connected in the axial direction by wire bonding. and a mounting structure for a solid-state imaging device for an electronic endoscope, characterized in that a mold covering the wire bonding portion is formed within the thickness of a cover glass disposed between the solid-state imaging device and the optical system.