JP3668331B2 - Imaging unit - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a small imaging unit used for an endoscope or the like, and more particularly to shortening the imaging unit in the length direction.
[0002]
[Prior art]
In recent years, various electronic endoscopes having an imaging unit including an objective lens, a solid-state imaging device, a circuit wiring board connected to the solid-state imaging device, and the like at the distal end portion of an insertion unit have been proposed and used.
[0003]
When such a small imaging unit is disposed at the distal end portion of the insertion portion of the electronic endoscope, the configuration of the signal transmission cable mounting portion is, for example, that shown in FIG. In the imaging unit of the first conventional example, the circuit wiring board 51 and the solid-state imaging device 52 are connected by a conductive material 53 such as solder, and then the internal cable 55 is stripped from the signal transmission cable 54 for connection. Cutting and processing to the required length, extending the signal transmission cable 54 to the end of the circuit wiring board 51, connecting the cable 55 with the conductive material 53 to the required location, and then shrinking The periphery of the circuit wiring board 51 is protected by the tube 56, and the signal transmission cable is fixed and attached by filling and hardening the insulating resin 57 inside.
[0004]
Another configuration example includes the configuration shown in FIG. In the imaging unit of the second conventional example, after the circuit wiring board 51 and the solid-state imaging device 52 are connected by the conductive material 53 in the same manner as in the configuration of FIG. Arranged in parallel, a metal cable fixing member 59 is fixed to the rear end side of these with a conductive material 53, and the cable 55 inside the signal transmission cable 54 extends along both the boards from the cable fixing member 59 side. With the outer conductor 60 of these cables 55 in contact with the cable fixing member 59, the end portions of the cables 55 are connected and fixed to the outer surfaces of the circuit wiring board 51 and the connection board 58 with the conductive material 53, respectively. After that, the periphery of the circuit wiring board 51 and the connection board 58 is protected by the shrinkable tube 56, and the inside is filled with an insulating resin 57 and cured to fix the signal transmission cable. It is with to perform Ri.
[0005]
[Problems to be solved by the invention]
In the configuration of the conventional imaging unit as described above, in the imaging unit shown in FIG. 12, the position of the cable bundle branching portion 61 of the signal transmission cable 54 is located behind the rear end portion of the circuit wiring board 51. . Therefore, in order to secure the fixed strength when the signal transmission cable 54 is attached, it is necessary to overlap the signal transmission cable 54 and the contraction tube 56. Therefore, as the end of the contraction tube 56 is located rearward, the imaging unit becomes more rigid. The part becomes long, and as a result, the hard part of the distal end part of the endoscope becomes long. Further, since the signal transmission cable 54 is held when it is fixed by the shrinkable tube 56 and the insulating resin 57, there are problems such as low fixing strength and difficulty in positioning the signal transmission cable.
[0006]
On the other hand, the imaging unit shown in FIG. 13 has a problem that the cable fixing member 59 is separately required in addition to the problem that the hard portion becomes long as described above, and the processing man-hour and the mounting man-hour increase. .
[0007]
The electronic endoscope is configured such that the distal end portion can be directed in a predetermined direction by bending a bending portion provided at the rear portion of the insertion portion distal end portion, and the distal end portion is preferably as short as possible. Therefore, it is desirable that an imaging unit incorporated in such an electronic endoscope or the like has a hard portion as short as possible.
[0008]
The present invention has been made in view of these circumstances, and can reduce the length of the hard portion without impairing the fixing strength of the signal transmission cable and the workability during assembly. An object of the present invention is to provide an imaging unit that can be made smaller.
[0009]
[Means for Solving the Problems]
An imaging unit of the present invention, versus objective lens and a solid-state imaging device for imaging an optical image wherein the objective lens is imaged, the other end portion side of the imaging with one end side is connected to the solid-state imaging device and arranged circuit wiring board so as to extend toward the rear end side of the unit, a signal transmission cable distal end portion is formed by bundling a plurality of cables to be electrically connected to the circuit wiring board, wherein A bundle branch portion that constitutes a tip portion of the signal transmission cable and the plurality of cables branch from the signal transmission cable, and the bundle branch portion provided on the circuit wiring board and a part of the signal transmission cable are sandwiched. And a cutout portion having a side surface to be fixed with.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
1 to 3 relate to a first embodiment of the present invention, FIG. 1 is a longitudinal sectional view showing a configuration of an image pickup unit, and FIG. 2 is a cross-sectional view showing the vicinity of a connection portion between a circuit wiring board and a signal transmission cable of the image pickup unit. FIG. 3 is an explanatory diagram showing a schematic configuration of the entire endoscope apparatus.
[0011]
In the present embodiment, a configuration example of an imaging unit disposed at the distal end portion of the insertion portion of the endoscope is shown. In the endoscope 1 on which the imaging unit of the present embodiment is mounted, an insertion portion 3 that is elongated and inserted into a subject such as a body cavity is extended in front of an operation portion 2 that also serves as a grip portion on the hand side. Configured. The insertion portion 3 is mainly composed of a flexible flexible tube 4, and a bending portion 5 that can be bent vertically and horizontally is connected to the distal end of the flexible tube 4, and a rigid distal end is provided in front of the bending portion 5. Part 6 is provided. The operation unit 2 is provided with a universal cord 7 in which a signal cable, a light guide fiber bundle and the like are provided from the side thereof. The universal cord 7 is connected to, for example, a light source via a connector 8 provided at an end portion. It is connected to a video processor 9 in which the apparatus is installed. Note that the video processor and the light source device may be separate. Further, the video processor 9 is connected to a monitor 11 via a signal cable 10, and an image of a region to be examined picked up by the endoscope 1 is signal-processed by the video processor 9 to the monitor 11. It is displayed and can be observed by the user.
[0012]
An imaging unit 12 as shown in FIGS. 1 and 2 is disposed at the distal end portion 6 of the endoscope 1. The imaging unit 12 includes an objective lens 13 that forms an image of a subject, and a solid-state imaging device such as a CCD that obtains an imaging signal by photoelectrically converting the subject optical image by arranging an imaging surface at an imaging position (focal position) of the objective lens 13. A signal transmission cable including a device 14, a circuit wiring board 15 connected to the solid-state imaging device 14 and performing processing such as signal amplification, and a coaxial cable connected to at least one of the solid-state imaging device 14 and the circuit wiring board 15. 16.
[0013]
A signal processing IC (not shown) is electrically and mechanically connected to the circuit wiring board 15 by die bonding, wire bonding, face down bonding such as TAB (Tape Automated Bonding), etc., and sealed with a sealing resin. Peripheral circuit components such as a capacitor 19 electrically and mechanically connected by the processing IC sealing portion 18 and the conductive material 21 are mounted.
[0014]
A procedure for fixing and attaching the signal transmission cable 16 in the imaging unit 12 of the present embodiment will be described with reference to FIGS. First, the outer lead 20 drawn out from the solid-state imaging device 14 and the circuit wiring board 15 are connected by the conductive material 21. Thereafter, the internal cable 22 is stripped from the signal transmission cable 16 and cut to a length necessary for the connection and processed, and the cut formed on the signal transmission cable 16 connection side at the end of the circuit wiring board 15 is performed. The distal end portion of the signal transmission cable 16 is inserted into the notch 23, and the cable 22 is connected to a necessary location such as the connection land 24 on the circuit wiring board 15 and the outer lead 20 of the solid-state imaging device 14 with the conductive material 21. And the front-end | tip part of the solid-state imaging device 14, the circuit wiring board 15, and the signal transmission cable 16 is protected by the shrinkable tube 25, and after filling the space inside the shrinkable tube 25 with the insulating resin 17, it hardens | cures and adheres. As a result, the adhesive such as the insulating resin 17 wraps around the notch 23, and the cable tip and the notch 23 are also cured and fixed.
[0015]
In the configuration of the present embodiment, the position of the front end of the cable after the signal transmission cable 16 is attached is shifted to the solid-state imaging device as a whole by the notch 23 provided on the rear end side of the circuit wiring board 15, Further, the cable 22 and the cable bundle branching portion 26 can be arranged on the inner side (front end side), so that the length of the contraction tube 25 for electrically and mechanically protecting the imaging unit 12 from the surrounding environment can be shortened. . Thereby, since the hard part length of the imaging unit 12 can be shortened, the length of the distal end hard part of the endoscope incorporating the imaging unit can be shortened, and the operability of the imaging device such as the endoscope can be improved. .
[0016]
In this embodiment, when the signal transmission cable 16 is connected to the circuit wiring board 15, the signal transmission cable 16 is accommodated in the notch 23 of the circuit wiring board 15, and the signal transmission cable 16 is formed on both sides of the notch 23. Since the signal transmission cable 16 can be positioned and fixed by inserting the pin, the fixing strength can be improved without using any other special fixing member. Furthermore, the signal transmission cable 16 and the notch 23 can be easily positioned by simply inserting the signal transmission cable 16 into the notch 23. Thereby, the efficiency of assembly work and the improvement of reliability can be aimed at.
[0017]
Next, as a modification of the first embodiment, a configuration example in which the arrangement configuration of peripheral circuit components such as a capacitor is changed in the second and third embodiments will be described.
[0018]
FIG. 4 is a cross-sectional view showing a configuration of an imaging unit according to the second embodiment of the present invention. The imaging unit 12 a of the second embodiment is configured by directly connecting an outer lead 20 drawn out from the solid-state imaging device 14 to a capacitor 19. Other parts are configured in the same manner as in the first embodiment.
[0019]
FIG. 5 is a cross-sectional view showing a configuration of an imaging unit according to the third embodiment of the present invention. The imaging unit 12b of the third embodiment is similar to the second embodiment in that the outer lead 20 of the solid-state imaging device 14 is bent and deformed in one direction so that the capacitor 19 is located in an empty space of the circuit wiring board 15. The outer lead 20 is directly connected to the capacitor 19. Other parts are configured in the same manner as in the first embodiment.
[0020]
According to these 2nd and 3rd embodiment, while being able to obtain the same effect as 1st Embodiment, size reduction of an imaging unit can be attained further.
[0021]
Next, as another modified example of the first embodiment, a configuration example in which the configuration of the connection portion between the solid-state imaging device and the circuit wiring board in the fourth and fifth embodiments is changed will be described.
[0022]
6 to 8 relate to the fourth embodiment of the present invention, FIG. 6 is a plan view showing the configuration of the connection portion between the solid-state imaging device and the circuit wiring board, and FIG. 7 is a longitudinal sectional view of the connection portion of FIG. 8 is a cross-sectional view taken along line AA of the circuit wiring board of FIG.
[0023]
In the fourth embodiment, a stepped portion 27 is provided on one end side of the circuit wiring board 15a, and a connection land 24 to which the solid-state imaging device 14 is connected electrically and mechanically is formed on the stepped portion 27 to form circuit wiring. The substrate 15a is configured. Other parts are configured in the same manner as in the first embodiment.
[0024]
With this configuration, it is possible to easily insert and connect the circuit wiring board 15 a between the leads of the outer lead 20 without deforming the outer lead 20 of the solid-state imaging device 14.
[0025]
9 to 11 relate to a fifth embodiment of the present invention, FIG. 9 is a plan view showing a configuration of a connecting portion between a solid-state imaging device and a circuit wiring board, and FIG. 10 is a longitudinal sectional view of the connecting portion of FIG. 11 is a cross-sectional view of the circuit wiring board of FIG. 9 taken along line BB.
[0026]
In the fifth embodiment, a groove portion 28 is provided on one end side of the circuit wiring board 15b, and a connection land 24 is formed in the groove portion 28 to constitute the circuit wiring board 15b. Other parts are configured in the same manner as in the first embodiment.
[0027]
With this configuration, the outer lead 20 and the connection land 24 of the circuit wiring board 15b can be connected without deforming the outer lead 20 of the solid-state imaging device 14, and the outer lead 20 of the solid-state imaging device 14 can be connected to the groove 28. Positioning is not required and the workability can be improved because positioning can be easily performed simply by inserting and connecting.
[0028]
In addition, it cannot be overemphasized that the imaging unit of this embodiment can be used not only in the endoscope mentioned in the example but in various imaging apparatuses.
[0029]
According to each of the above embodiments, since the notch portion is provided in the circuit wiring board, the position of the connection portion at the tip of the signal transmission cable can be placed on the solid-state imaging device side with the circuit wiring board being inserted into the circuit wiring board. It is possible to shorten the length of the hard end portion of the imaging device such as a mirror. In addition, since the end of the signal transmission cable is positioned by the notch, work efficiency can be improved, and reliability can be improved in that the fixing strength of the signal transmission cable can be ensured. be able to.
[0030]
[Appendix]
(1) An objective lens, a solid-state imaging device having its imaging surface positioned at the focal position of the objective lens, a circuit wiring board connected to the solid-state imaging device, and at least the solid-state imaging device or the circuit wiring board In an imaging unit comprising a signal transmission cable connected to one side,
An imaging unit, wherein a notch portion for accommodating a tip end portion of the signal transmission cable is provided on the signal transmission cable connecting portion side of the circuit wiring board.
[0031]
(2) The imaging unit according to appendix 1, wherein a cable bundle branching portion of the signal transmission cable is installed in the vicinity of the notch.
[0032]
(3) The imaging unit according to appendix 2, wherein a cable bundle branching portion disposed in the vicinity of the notch portion is positioned in a distal direction from a signal transmission cable side end portion of the circuit wiring board.
[0033]
(4) The imaging unit according to appendix 1, wherein a tip portion of the signal transmission cable is fixed by an adhesive at the notch portion.
[0034]
【The invention's effect】
As described above, according to the present invention, the length of the hard portion can be shortened without impairing the fixing strength of the signal transmission cable and the workability during assembly, and the tip portion of the endoscope incorporating the unit can be downsized. There is an effect that becomes possible.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing a configuration of an imaging unit according to a first embodiment of the present invention. FIG. 2 shows a vicinity of a connection portion between a circuit wiring board and a signal transmission cable of the imaging unit according to the first embodiment. FIG. 3 is an explanatory view showing a schematic configuration of the entire endoscope apparatus. FIG. 4 is a cross sectional view showing a configuration of an imaging unit according to the second embodiment of the present invention. FIG. 6 is a cross-sectional view illustrating a configuration of an imaging unit according to the third embodiment. FIG. 6 is a plan view illustrating a configuration of a connection portion between a solid-state imaging device according to a fourth embodiment of the present invention and a circuit wiring board. 6 is a vertical cross-sectional view of the connection portion of FIG. 6. FIG. 8 is a cross-sectional view of the circuit wiring board of FIG. 6 along the line AA. FIG. 9 is a connection between the solid-state imaging device according to the fifth embodiment of the present invention and the circuit wiring board. FIG. 10 is a plan view showing the configuration of the connection part. FIG. 10 is a longitudinal sectional view of the connection part in FIG. 9. FIG. Sectional view and FIG. 12 is an explanatory diagram showing a second configuration example of a first explanatory diagram illustrating a configuration example of FIG. 13 conventional image pickup unit of a conventional image pickup unit EXPLANATION OF REFERENCE NUMERALS
DESCRIPTION OF SYMBOLS 1 ... Endoscope 3 ... Insertion part 6 ... Tip part 12 ... Imaging unit 14 ... Solid-state imaging device 15 ... Circuit wiring board 16 ... Signal transmission cable 17 ... Insulating resin 18 ... Signal processing IC sealing part 19 ... Capacitor 20 ... Outer lead 21 ... Conductive material 22 ... Cable 23 ... Notch 24 ... Connection land 25 ... Shrink tube 26 ... Cable bundle branching part

Claims (1)

A pair objective lens,
A solid-state imaging device for imaging an optical image formed by the objective lens ;
A circuit wiring board disposed so that one end thereof is connected to the solid-state imaging device and the other end extends toward the rear end of the imaging unit;
A signal transmission cable formed by bundling a plurality of cables whose front ends are electrically connected to the circuit wiring board ;
A bundled branch portion that forms the tip of the signal transmission cable and branches the plurality of cables from the signal transmission cable;
A notch portion having a side surface provided on the circuit wiring board for sandwiching and fixing the bundle branch portion and a part of the signal transmission cable ;
An imaging unit comprising:

Images