JPH046964A - Solid-state image pickup device - Google Patents

Abstract

PURPOSE:To obtain excellent picture quality by using a heat pipe so as to couple a color separation prism mount of a case with a package face of a solid-state image pickup element fixed in the vicinity of a light radiation face of a color separation prism so as to prevent temperature rise of the solid-state image pickup element. CONSTITUTION:A mount 9 of a color separation prism 3 of a case 2 and a package face of a solid-state image pickup element 4 fixed to a radiating face 10 of the color separation film 3 via a glass piece 11 have a same height of end face 13. A sheet shaped heat pipe 5 is arranged to the end face 13. The contact between the heat pipe 5 and the color separation prism mount 9 is fixed with an adhesives added with a metal whose thermal conductivity is excellent and the heat pipe 5 and the package face of an image pickup element are connected by using grease whose thermal conductivity is excellent. Through the constitution above, the temperature rise of the solid-state image pickup element is suppressed with simple constitution and excellent picture quality is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a solid-state color imaging device using a solid-state imaging device such as a charge-coupled device (COD), and particularly relates to suppressing temperature rise of the solid-state imaging device and improving image quality. It is something.

Conventional technology In a solid-state color imaging device, imaging light from a lens is separated into a red component, a green component, and a blue component using a color separation prism, and a subject image of each color component is captured using each solid-state imaging device. A standard color television signal is formed from each image pickup output and output.

Conventionally, in solid-state imaging devices using multiple solid-state imaging devices,
Each solid-state image sensor is fixed to a color separation prism in a state in which the object image of each color component imaged by each solid-state image sensor is accurately adjusted to a predetermined position (registration adjustment). A peripheral circuit board on which a bias circuit, a dry circuit, a preamplifier circuit, etc. are formed is arranged in the vicinity of the solid-state imaging device attached to the color separation prism to the casing of the solid-state imaging device and fixed to the color separation prism. It is set up.

Problems to be Solved by the Invention In the solid-state image sensor used in a solid-state image sensor, the dark current of a specific pixel increases significantly, and the specific pixel portion appears white in a dark state, and its contrast depends on the rise in temperature. There were defects (referred to as white scratches) that increased. These defects have an approximately 2-fold increase in contrast at approximately 10°C;
There was a problem that the image quality deteriorated significantly. The self-heating of the solid-state image sensor itself is about 0.3 to 0.6 W, and it is also affected by the peripheral circuit board that forms the bias circuit, drive circuit, preamplifier circuit, etc. near the solid-state image sensor, and the solid-state image sensor package In our solid-state imaging device, the surface temperature rises by about 20 degrees Celsius relative to the ambient temperature.

As a solution to this problem, a method of cooling the solid-state image sensor by providing an electronic cooling element (Peltier effect) on the package surface is often used. However, in these methods, if the heat dissipation structure of the electronic cooling element is not sufficiently provided, there is a risk that the opposite result will occur, such that the electronic cooling element heats the solid-state image sensor instead of a heat generator. Moreover, it requires excessive power consumption, and since a solid-state imaging device for reporting uses a power source such as a power source, an increase in power consumption becomes a big problem.

In view of this, an object of the present invention is to provide a solid-state imaging device that has a simple configuration and suppresses the temperature rise of a solid-state imaging element without requiring special power consumption and has good image quality.

Means for Solving the Problems In order to solve the above problems, tentative means of the present invention are as follows:
Lens mount section, color temperature conversion and light intensity adjustment (ND)
The color separation prism mounting part of the casing has a filter housing part and a color separation prism mounting part, and the package surface of the solid-state image sensor fixed near the projection surface of the color separation prism is attached to a sheet-like (cross-sectional) A rectangular parallelepiped heat pipe has one side fixed with an adhesive containing a metal with good thermal conductivity, and the other side thermally bonded with a grease substance with good thermal conductivity.

Effect of the Invention With the above configuration, the present invention enables a solid-state imaging device with a simple configuration, which suppresses the temperature rise of the solid-state imaging element without requiring special power consumption, and has good image quality.

Embodiment 1 A method for cooling a solid-state image sensor used in a three-plate color image sensor, which is an embodiment of the present invention.

This will be explained in detail using figures. FIG. 1 is a schematic diagram showing the configuration of the present invention, and FIG. 2 is a partial view of FIG. 1 is the camera lens, 2 is the housing.

3 is a color separation prism, 4 is a solid-state image sensor, 6 is a heat pipe, and 6 is a circuit board. The housing 2 has a lens attachment part 7, a housing part 8 for a color temperature and light amount adjustment filter, and a color separation prism attachment part 9, and is made of aluminum or the like having good thermal conductivity. Solid-state imaging devices 4R, 4G, 4B are mounted on the respective light emitting surfaces 1oR, 1oc, 10B of the color separation prism 3, with the subject images of each color component being accurately adjusted to predetermined positions (registration adjustment).
are fixed via glass pines 11. A part of the color separation prism mounting section 9 is attached to the package surface 12 of the solid-state image sensor in order to transfer the heat of the heat pipe to the housing.
It has an end surface 13 of the same height. A heat vibro in the form of a sheet (rectangular parallelepiped in cross section) is disposed on the package surface 12 and the end surface 13 of the solid-state image sensor, and the contact portion between the pan cage surface 12 and the heat vibro is fixed with a silver paste having good thermal conductivity. The contact portion between the end surface 13 and the heat vibro is thermally coupled with a paste-like substance (grease) that has good thermal conductivity and does not solidify. Further, a circuit board 6 is soldered to the terminal of each solid-state imaging device 4.

Conventional heat pipes have a circular cross section, so when heat pipes are used to transfer heat between planar members, the contact area becomes a line contact, resulting in insufficient heat transfer. As mentioned above,
By using a heat vibro sheet-like (rectangular parallelepiped cross section), the contact area between the heat vibro and the package surface 12 of the solid-state image sensor can be increased, improving heat transfer efficiency.
Furthermore, the heat transfer efficiency between the heat vibro and the end surface 13 is also improved.

By thermally bonding the contact portion between the end surface 13 and the heat pipe 5 with a paste-like substance (grease) that has good thermal conductivity and does not solidify, the color separation prism 3 remains stable even when the temperature changes. Image quality is stabilized because no stress is applied to each solid-state image pickup device that has been accurately adjusted (registration adjustment) and fixed.

FIG. 3 shows the results of a comparison of the temperature rise of the solid-state imaging device in our solid-state imaging device when the thermoelectric cooling element is not used or when the pipe is not used and when the present invention is used. A shows a temperature rise curve when neither the electronic cooling element nor a heat pipe is used, and b shows a temperature rise curve when the present invention is used. According to the present invention, the temperature rise is significantly suppressed as is clear from the figure. Furthermore, the effect of this example was comparable to the effect when using the electronic cooling element shown in the conventional example.

The temperature rise of the solid-state image sensor is approximately 3° C. compared to the temperature outside the casing.

Of course, the contact area between the package surface 12 and the Heat Vibro is thermally bonded with a paste-like substance (grease) that has good thermal conductivity and does not solidify, and the contact area between the end surface 13 and the Heat Vibro is connected with a thermally conductive material. The same effect can be obtained by fixing with a good silver paste.

Effects of the Invention As described above, according to the present invention, the temperature rise of the solid-state image sensor can be suppressed with a simple configuration at low cost, and without requiring special power consumption, and defects such as white scratches can be suppressed. This makes it possible to provide a solid-state imaging device with good image quality.

[Brief explanation of drawings]

FIG. 1 is a side view showing the configuration of an embodiment of the solid-state image sensor of the present invention, and FIG. 2 is a partially enlarged view of the embodiment. FIG. 3 is a characteristic diagram showing a comparison of the temperature rise of the solid-state image sensing device in the case where neither the electronic cooling element nor the heat pipe is used and the case according to this embodiment. 1... Camera lens, 2... Housing, 3
......Color separation prism, 4...Solid-state image sensor, 6...Heat pipe, 6...Circuit board, 7...Lens mounting part , 8... Housing part, 9... Color separation prism installation part,
1o...Glass piece. Name of agent: Patent attorney Shigetaka Awano and 1 other person-e
Ih Moblis''4

Claims (4)

[Claims] (1) Lens mount and color temperature conversion and light intensity adjustment (
ND) The color separation prism attachment part of the casing having the filter housing part and the color separation prism attachment part and the package surface of the solid-state image sensor fixed in the vicinity of the output surface of the color separation prism are connected by heat pipe. Characteristic solid-state imaging device. (2) The solid-state imaging device according to claim 1, wherein the heat pipe is sheet-shaped (rectangular parallelepiped in cross section). (3) The contact part between the heat pipe and the package surface of the solid-state image sensor is fixed with an adhesive containing a metal with good thermal conductivity, and the contact part between the other heat pipe and the color separation prism mounting part is fixed with a metal-added adhesive that has good heat conduction. 2. The solid-state imaging device according to claim 1, wherein the solid-state imaging device is connected with good grease. (4) The contact area between the heat pipe and the color separation prism attachment part is fixed with an adhesive containing a metal with good thermal conductivity, and the contact area between the other heat pipe and the package surface of the solid-state image sensor has good thermal conductivity. 2. The solid-state imaging device according to claim 1, wherein the solid-state imaging device is connected with grease.