JPS6317260Y2 - - Google Patents

Description

[Detailed description of the invention] (a) Technical field of the invention The present invention relates to improvement of a cooled photoelectric conversion device, and in particular improves the field of view of incident light to an infrared detection photoelectric conversion element placed on a cooling base of the device. This invention relates to a cold shield arrangement structure for defining corners.

(b) Background of the Technology Infrared detection devices, which are generally referred to as cooled photoelectric conversion devices, consist of an outer cylinder made of a glass tube equipped with an infrared transmission window, and a cooling unit in which an infrared detection element is arranged in relation to the transmission window. The main body is a vacuum insulated container with a dewar structure consisting of an inner cylinder, and further has an aperture on the front surface of the infrared detection element for determining the field of view to define the range of infrared rays incident on the detection element from the transmission window. cold shield,
A configuration is adopted in which the detection element is arranged to surround the detection element. The infrared sensing element, including the cold shield unit, is cooled to a low temperature through the cooling unit using a liquid refrigerant such as liquid nitrogen, a Joel Thompson type cooler, a He gas circulation type refrigerator, etc. It's working. However, when the sensing element is operated at low temperatures, vibrations caused by the operation of the cooler or freezer, vibrations applied from the holding part of the device, and even external sources are transmitted to the cold shield unit, causing microphonic noise. There is a problem in that noise occurs, degrading the signal output of the device, and it is desired to prevent the occurrence of such noise.

(c) Prior Art and Problems Figures 1 and 2 are a top view and a side sectional view of the main parts of the arrangement structure of the cold shield unit in the conventional infrared detection device described above. It is an inner cylinder equipped with a cooling base 2, and numeral 3 is an infrared detection element placed on the cooling base 2 with an insulating plate 4 made of sapphire or the like interposed therebetween. In the cross section above the infrared detecting element 3, a cold shield support cylinder 5a with blackened inner and outer circumferential surfaces, for example, surrounds the detecting element 3.
As shown in the figure, the opening 5 is similar to the first cold shield plate 5b, which is provided with a viewing angle determining opening 5c that defines the viewing angle of the incident light on the detection element 3.
A cold shield unit 5 is fixed to the side of the cooling base 2, which is combined with a second cold shield plate 5d having holes e. For example, a He gas circulation refrigerator is inserted into the inner cylinder 1, and the infrared detecting element 3 is cooled to a predetermined low temperature together with the cold shield unit 5 via the cooling base 2. .

However, in the conventional cold shield unit 5 arranged as described above, the first and second cold shield plates 5b and 5d having a thickness of, for example, about 0.2 mm are combined with the cold shield support tube 5a, and the cold shield unit 5 is arranged as described above. Since the shield unit 5 is fixed at two locations on the side of the cooling base 2, it is free from slight vibrations or other vibrations that occur when the He gas circulation type refrigerator inserted in the inner cylinder 1 is driven. When the vibration transmitted from the device support part of the cold shield unit 5 is transmitted to the cold shield unit 5, the first cold shield unit made of a thin plate
The second cold shield plates 5b and 5d also vibrate, and this mechanical vibration generates microphonic noise, which has the drawback of deteriorating the signal output of the detection device.

(d) Purpose of the invention In order to eliminate the above-mentioned drawbacks of the conventional method, the present invention provides a cold shield unit with a thick integral structure that does not resonate due to vibrations from refrigerators, etc., and a wide contact surface with the cooling base. By fixing with
It is an object of the present invention to provide a novel cooling type photoelectric conversion device that can prevent the generation of microphonic noise caused by vibration.

(e) Structure of the invention According to the invention, the above object is to provide an opening having a tapered shape at a predetermined angle for determining the field of view for the photoelectric conversion element on the upper surface of the cooling base on which the photoelectric conversion element is arranged. The upper plate part and the support part are configured to have a cold shield fixed thereto, which is made of a single integral component, and the field of view for the photoelectric conversion element is determined by the upper surface and the lower surface of the upper plate part. This is achieved by providing a cooled photoelectric conversion device characterized by the following.

(f) Embodiments of the invention Examples of the invention will be described below in detail with reference to the drawings.

FIGS. 3 and 4 are a top view and a side sectional view of a main part showing an example of the structure and arrangement of a cold shield in an infrared detection device to which the present invention is applied. As is clear in both figures, 21 is an inner cylinder equipped with a cooling base 22;
Reference numeral 23 denotes an infrared detecting element disposed on the cooling base 22 with an insulating plate 24 made of sapphire, ceramic, etc. interposed therebetween. Reference numerals 25 and 26 designate ceramic terminal boards for wiring on which a wiring pattern (not shown) for extracting signal output from the infrared detecting element 23 is provided. The cooling base 22 on which the infrared detecting element 23 is disposed in this way
Above, as shown in FIG.
A support part 29 and an upper plate part 30 provided with an aperture part 28 having a taper for visual field determination that defines the range of infrared rays incident on the part 3 are integrally constructed, and surround the infrared detecting element 23. The cold shield 27, which is a feature of the present invention and consists of a thick rectangular box-shaped single component, is stably fixed by, for example, welding, with a sufficient contact surface. In addition, to further explain the cold shield 27 of the present invention,
In order to eliminate easy resonance caused by the vibration of the refrigerator, the wall thickness around the opening 28 may be reduced to 1.
~2mm, and the other parts are at least 0.5mm thick.The inner and outer periphery of the The surface is black-treated. Therefore, by configuring and arranging the cold shield 27 as described above, it is possible to prevent resonance caused by vibrations from the refrigerator, etc., without impairing its function, thereby reducing microphonic noise caused by vibrations. It becomes possible to completely eliminate the occurrence of Furthermore, in order to fix the cold shield 27 on the cooling base 22, a metal solder foil with a low melting point is interposed between the cooling base 22 and the fixing surface of the cold shield 27, and the two are soldered together. You may also do so.

(g) Effect of the invention As is clear from the above explanation, according to the cooled photoelectric conversion device according to the present invention, the photoelectric conversion device is mounted on the cooling base on which the photoelectric conversion element is arranged, by means of a thick member. A structure is adopted in which a cold shield consisting of a single component consisting of an upper plate part with an opening for the photoelectric conversion element and a support part is fixed so as to surround the conversion element, so that the cold shield is fixed in place so as to surround the conversion element. This prevents the cold shield from resonating due to the vibrations that occur, and as a result, the generation of microphonic noise caused by the resonance is completely eliminated, and the signal output of the device is no longer degraded. Demonstrates excellent effects. Therefore, it is extremely advantageous to apply this type of cooling type photoelectric conversion device.

[Brief explanation of the drawing]

Figures 1 and 2 are a top view and a sectional side view of the main parts to explain the arrangement structure of a cold shield unit in a conventional cooled photoelectric conversion device for infrared detection, and Figures 3 and 4 are views to which the present invention is applied. FIG. 5 is a top view and a sectional side view of a main part of an embodiment of the arrangement structure of a cold shield in an infrared detection device, and FIG. 5 is a perspective view of an embodiment of the structure of the cold shield according to the present invention. In the drawing, 21 is an inner cylinder, 22 is a cooling base, 2
3 is an infrared detection element, 24 is an insulating plate, 25, 26
2 is a ceramic terminal board for wiring, 27 is a cold shield, 28 is an opening, 29 is a support portion, and 30 is an upper plate portion.

Claims (1)

[Claims for Utility Model Registration] A cooling type photoelectric conversion device in which a refrigerator or the like is inserted into an inner cylinder 21, and the refrigerator is used to cool an infrared detection element 23 together with a cold shield 27 via a cooling base 22. , a cooling base 2 attached to the upper end of the inner cylinder 21
A photoelectric conversion element 23 is provided on the upper surface of the photoelectric conversion element 23, and a cold shield 27, which is made of a single component in which an upper plate part 30 having an opening 28 and a support part 29 are integrated, is placed close to the photoelectric conversion element 23. A cooling type photoelectric conversion device, characterized in that the device is fixed to a cooling base 22, and the field of view for the photoelectric conversion element 23 is determined by the upper and lower surfaces of the upper plate portion 30.