Thermoelectric cooling management

Patent metadata

Field	Value
Publication number	US-10295230-B2
Application number	US-201615099958-A
Country	US
Kind code	B2
Filing date	Apr 15, 2016
Priority date	Apr 15, 2016
Publication date	May 21, 2019
Grant date	May 21, 2019

Abstract

A method of controlling FPA system stabilization includes calculating FPA adjustments as a function of FPA temperature and adjusting a TEC set point to assist the FPA adjustments in attaining a predetermined level of FPA performance. Adjusting the TEC set point can include adjusting the TEC set point as a function of at least one of ambient temperature, FPA temperature, or disparity between the predetermined level of FPA performance and a level of FPA performance obtainable by calculating the FPA adjustments as a function of FPA temperature alone without adjusting the TEC set point.

First claim

What is claimed is:

1. A method of controlling FPA system stabilization comprising:
calculating FPA adjustments as a function of FPA temperature; and
adjusting a TEC set point to assist the FPA adjustments in attaining a predetermined level of FPA performance, wherein calculating FPA adjustments includes:
determining an FPA temperature;
calculating an FPA system gain as a function of the FPA temperature;
applying the FPA system gain at the FPA temperature to condition output of the FPA to produce temperature independent image data at the TEC set point;
calculating a non-uniformity correction map on a pixel by pixel basis for the FPA, wherein non-uniformity correction for each pixel is a function of the FPA temperature; and
applying the non-uniformity correction map to the imaging data from the FPA to produce temperature dependent non-uniformity corrected image data at the TEC set point, wherein calculating the non-uniformity correction map includes a process that does not itself perform a system gain correction in calculating the non-uniformity correction map.

2. A method as recited in claim 1 , wherein adjusting the TEC set point includes adjusting the TEC set point as a function of at least one of ambient temperature, FPA temperature, or disparity between the predetermined level of FPA performance and a level of FPA performance obtainable by calculating the FPA adjustments as a function of FPA temperature alone without adjusting the TEC set point.

3. A method as recited in claim 1 , wherein adjusting the TEC set point includes prompting a user to approve adjusting TEC set point to reach the predetermined level of FPA performance.

4. A method as recited in claim 1 , wherein adjusting the TEC set point includes automatically adjusting the TEC set point.

5. The method as recited in claim 1 , wherein calculating the FPA system gain includes calculating the FPA system gain as a function of system gain for the FPA at a reference temperature and empirically derived coefficients.

6. The method as recited in claim 1 , wherein non-uniformity correction for each pixel is a function of empirically derived coefficients.

7. The method as recited in claim 1 , wherein applying the FPA system gain includes applying the FPA system gain to a ROTC operatively connected to the FPA to condition electrical signals from the FPA for imaging.

8. The method as recited in claim 1 , further comprising:
receiving the imaging data from the FPA, wherein receiving imaging data from the FPA includes transmitting the imaging data to the ROIC from the FPA, wherein the ROIC is operatively connected to the FPA to condition electrical signals from the FPA for imaging.

9. The method as recited in claim 8 , wherein applying the non-uniformity correction map to the imaging data includes applying the non-uniformity correction map to the imaging data from the ROIC.

10. A method of controlling FPA system stabilization comprising:
calculating FPA adjustments as a function of FPA temperature; and

adjusting a TEC set point to assist the FPA adjustments in attaining a predetermined level of FPA performance, wherein calculating FPA adjustments includes:
determining an FPA temperature;
calculating an FPA system gain as a function of the FPA temperature;
applying the FPA system gain at the FPA temperature to condition output of the FPA to produce temperature independent image data at the TEC set point;
calculating a non-uniformity correction map on a pixel by pixel basis for the FPA, wherein non-uniformity correction for each pixel is a function of the FPA temperature; and
applying the non-uniformity correction map to the imaging data from the FPA to produce temperature dependent non-uniformity corrected image data at the TEC set point, wherein calculating the FPA system gain is governed by
V gain( T ) =[( p 1 + p 3*Tref)* V gainref + p 2*(Tref− T )]/( p 1 + p 3* T )

wherein Vgain is a variable control level which correlates to the FPA system gain, Vgainref is the value of the control level which sets the FPA system gain at the reference temperature (Tref), and p 1 , p 2 , and p 3 are empirically derived coefficients.

11. A method of controlling FPA system stabilization comprising:
calculating FPA adjustments as a function of FPA temperature; and

adjusting a TEC set point to assist the FPA adjustments in attaining a predetermined level of FPA performance, wherein calculating FPA adjustments includes:
determining an FPA temperature;
calculating an FPA system gain as a function of the FPA temperature;
applying the FPA system gain at the FPA temperature to condition output of the FPA to produce temperature independent image data at the TEC set point;
calculating a non-uniformity correction map on a pixel by pixel basis for the FPA, wherein non-uniformity correction for each pixel is a function of the FPA temperature; and
applying the non-uniformity correction map to the imaging data from the FPA to produce temperature dependent non-uniformity corrected image data at the TEC set point, wherein calculating a non-uniformity correction map on a pixel by pixel basis is governed by

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Assignees

• Sensors Unlimited Inc

Inventors

• Nazemi Jonathan
• Delamere Michael
• Hansen Marc
• Yu Jinguo

Classifications

• F25B21/02 Primary

  using Peltier effect; using Nernst-Ettinghausen effect · CPC title

• H04N5/33

  Transforming infrared radiation (cameras or camera modules for generating image signals from infrared radiation H04N23/20; circuitry of SSIS for transforming infrared radiation into image signals H04N25/20) · CPC title

• H04N23/20

  for generating image signals from infrared radiation only · CPC title