RU2539791C1 - Cooled photodetector base - Google Patents

Abstract

FIELD: physics.

SUBSTANCE: cooled photodetector base is made of material having a thermal expansion coefficient equal to or close to that of the cooled element and, in order to reduce cooling non-uniformity, an opening passes through the entire length of the base, wherein a heat pipe is placed in said opening, and the remaining gap between the heat pipe and the opening of the base is filled with gallium to form a mechanical bond with good thermal conductivity.

EFFECT: invention considerably reduces the temperature gradient when cooling large photodetectors made on both a single substrate and assembled from multiple units.

2 dwg

Description

The present invention relates to cooling systems for photodetectors and can be used in equipment for various purposes, especially in large format thermal imaging or heat direction finding devices.

Known cooled photodetector [patent US 20110080483], comprising a cooling system and a sealed evacuated or gas-filled housing with an inlet window, inside of which a photosensitive structure with elements formed on it is placed on the cooled holder. The cooling system is a heat-conducting cylinder, at the end of which is a photosensitive structure. The disadvantage of this design is the uneven cooling of extended multi-element structures.

With a significant increase in the number of photosensitive elements, the size of the cryostatic zone and, accordingly, the cooled base increases significantly.

With an increase in the size of the cooled base, the problem of uniform cooling of the photosensitive region arises. Uneven cooling leads to a decrease in receiver performance.

The present invention can significantly reduce the temperature gradient during cooling of large-format photodetectors made both on one substrate and assembled from several modules.

The problem is solved in that the base to be cooled is made of a material having a coefficient of thermal expansion that is the same or close to the element to be cooled, and to reduce the unevenness of cooling, a hole passes through the entire length of the base, into which the heat pipe is placed, and the remaining gap between the heat pipe and the base hole is filled with gallium , forming a mechanical bond with good thermal conductivity.

The choice of gallium having a low melting point is determined by the possibility of multiple dismantling of the heat pipe.

A heat pipe passing through the entire length of the base can significantly reduce the temperature gradient between the extreme points of the base and reduce the time to reach the operating temperature. The gap between the base and the heat pipe is filled with gallium or a similar low-melting material, which ensures good heat transfer, ease of installation and reliable design. To protect against leakage of gallium from the gap, a ring is installed.

The invention is illustrated by drawings, where:

Figure 1. The design of the cooled base is presented:

1 - Plane for installation of cooled elements or modules.

2 - A hole for installing a heat pipe.

Figure 2. Base assembly with heat pipe:

3 - The gap between the heat pipe and the base, filled with gallium.

4 - Heat pipe.

The combination of the described design features made it possible to create a heat-conducting base for the cooled structures, which has a temperature gradient at the start and end point of no more than 0.5 ° C.

Claims (1)

The cooled base of the photodetector made of a material having a coefficient of thermal expansion that is the same or close to the cooled element, characterized in that, in order to reduce the unevenness of cooling, a hole passes through the entire length of the base, into which the heat pipe is placed, and the remaining gap between the heat pipe and the base is filled with gallium, to form a mechanical bond with good thermal conductivity, and is closed by a ring that prevents leakage of gallium.

Images