Optical refrigerator and sensor including such a refrigerator

Patent metadata

Field	Value
Publication number	US-11137176-B2
Application number	US-201816498692-A
Country	US
Kind code	B2
Filing date	Mar 15, 2018
Priority date	Mar 29, 2017
Publication date	Oct 5, 2021
Grant date	Oct 5, 2021

Abstract

An optical refrigerator for cooling an infrared detector or sensor, that includes a laser radiation source, a cooling crystal for receiving laser radiation from the source and to be cooled, an element to be cooled, and a thermal link in heat exchange between the crystal and the element to be cooled, in order to transfer frigories from the crystal to the element to be cooled. The thermal link comprises two plates having respective first ends in heat exchange with two distinct surfaces of the crystal, respectively, the two plates having second ends in heat exchange with the element to be cooled.

First claim

What is claimed is:

1. An optical refrigerator for cooling an infrared detector or sensor, the refrigerator comprising a source of laser radiation, a cooling crystal configured to receive the laser radiation from the source and to be cooled, an element to be cooled and a thermal link in heat exchange between the crystal and the element to be cooled in order to transfer frigories from the crystal to the element to be cooled, wherein the thermal link comprises two plates having respective first ends in heat exchange with two distinct surfaces of the crystal, respectively, and respective second ends in heat exchange with the element to be cooled.

2. The refrigerator of claim 1 , wherein one of the second ends is in heat exchange with one surface of the element to be cooled that is distinct from another surface of the element to be cooled that is in heat exchange with the other of the second ends.

3. The refrigerator of claim 2 , wherein the second ends of the two plates sandwich the element to be cooled.

4. The refrigerator of claim 1 , wherein the first ends of the two plates sandwich the crystal.

5. The refrigerator of claim 1 , wherein:
the plates each have a “J” or doglegged shape that extends in a plane non-rectilinearly; and
the ends of the plate in heat exchange with the crystal and the element to be cooled, respectively, are located at two ends located on either side of a dogleg or corner, respectively.

6. The refrigerator of claim 1 , wherein the plates are made of a transparent material.

7. The refrigerator of claim 6 , wherein the plates are made of glass or sapphire.

8. The refrigerator of claim 1 , further comprising at least two mirrors placed around the crystal in order to concentrate the light in the crystal.

9. The refrigerator of claim 1 , further comprising baffles for absorbing the light radiation generated by the crystal, the baffles being placed around the crystal.

10. The refrigerator of claim 9 , further comprising baffles for absorbing the light radiation generated by the crystal also around the faces of the crystal that are linked to the plates.

11. The refrigerator of claim 1 , wherein the element to be cooled is a cold finger or a focal plane intended to transfer frigories to a load.

12. A detector comprising a measuring unit and refrigerator of the measuring unit, wherein the refrigerator is the refrigerator of claim 1 .

Assignees

• Air Liquide

Inventors

• Niot Jean-Michel
• Gardelein Arnaud

Classifications

• H01S3/042

  for solid state lasers {(H01S3/0401 takes precedence)} · CPC title

• G01J1/0252

  Constructional arrangements for compensating for fluctuations caused by, e.g. temperature, or using cooling or temperature stabilization of parts of the device; Controlling the atmosphere inside a photometer; Purge systems, cleaning devices (protection against electromagnetic interferences G01J2001/0276) · CPC title

• F25B23/00 Primary

  Machines, plants or systems, with a single mode of operation not covered by groups F25B1/00 - F25B21/00, e.g. using selective radiation effect · CPC title

• F25B23/003 Primary

  using selective radiation effect · CPC title