Infrared camera calibration techniques

• US 9,143,703 B2
• Filed: 06/07/2012
• Issued: 09/22/2015
• Est. Priority Date: 06/10/2011
• Status: Active Grant

• Current Assignee: Teledyne FLIR LLC (Teledyne Technologies Incorporated)
• Original Assignee: FLIR Systems, Inc. (Teledyne Technologies Incorporated)
• Inventors: Boulanger, Pierre, Hoelter, Theodore R., Sharp, Barbara, Kurth, Eric A.
• Primary Examiner(s): Green, Yara B
• Application Number:
  US13/491,428
• Publication Number:
  US 20120312976A1
• Time in Patent Office: 1,202 Days
• US Class Current: 1/1
• CPC Class Codes: G01J 5/00 Radiation pyrometry, e.g. infrared or optical thermometry
• CPC Class Codes: G01J 5/02 Constructional details
• CPC Class Codes: G01J 5/20 using resistors, thermistors or semiconductors sensitive to radiation, e.g. photoconductive devices
• CPC Class Codes: G01J 5/53 Reference sources, e.g. standard lamps; Black bodies
• CPC Class Codes: G06V 20/52 Surveillance or monitoring of activities, e.g. for recognising suspicious objects recognising microscopic objects G06V20/69
• CPC Class Codes: H04N 17/002 for television cameras
• CPC Class Codes: H04N 23/11 for generating image signals from visible and infrared light wavelengths
• CPC Class Codes: H04N 23/57 Mechanical or electrical details of cameras or camera modules specially adapted for being embedded in other devices
• CPC Class Codes: H04N 23/71 Circuitry for evaluating the brightness variation
• CPC Class Codes: H04N 23/74 by influencing the scene brightness using illuminating means
• CPC Class Codes: H04N 5/33 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 Class Codes: H04N 7/18 Closed-circuit television [CCTV] systems, i.e. systems in which the video signal is not broadcast

Abstract

Various techniques are disclosed for testing and/or calibrating infrared imaging modules. For example, a method of calibrating an infrared imaging module may include providing a plurality of temperature controlled environments. The method may also include transporting the infrared imaging module through the environments. The method may also include performing a measurement in each environment using an infrared sensor assembly of the infrared imaging module and determining a plurality of calibration values for the infrared imaging module based on the measurements.

Claims

1. A method of calibrating an infrared imaging module, the method comprising:

providing a plurality of temperature controlled environments;

inserting the infrared imaging module into a socket;

transporting the infrared imaging module through the environments;

performing measurements in each environment using a plurality of infrared sensors of the infrared imaging module to receive infrared radiation associated with each environment; and

determining a plurality of calibration values for the infrared imaging module based on the measurements, wherein each infrared sensor has an associated calibration value for each of the environments.

2. The method of claim 1, wherein the transporting comprises continuously transporting the infrared imaging module through the environments.

3. The method of claim 1, further comprising storing the calibration values in a single table.

4. The method of claim 1, wherein the performing measurements further comprises providing test signals to the infrared imaging module through the socket.

5. The method of claim 1, wherein the calibration values include non-uniformity correction (NUC) values.

6. The method of claim 1, wherein each temperature controlled environment exhibits a corresponding ambient temperature greater than or less than an associated measurement temperature of the infrared imaging module to slew a current temperature of the infrared imaging module to the associated measurement temperature.

7. The method of claim 1, wherein the infrared imaging module is maintained in the environments for time periods approximately equal to two thirds of a thermal time constant associated with the infrared imaging module.

8. An apparatus comprising:

a plurality of partitions adapted to substantially separate a plurality of temperature controlled environments;

a conveyor adapted to receive a plurality of infrared imaging modules and transport the infrared imaging modules through the environments; and

a test equipment adapted to provide a plurality of test signals to the infrared imaging modules to cause a plurality of infrared sensors of each infrared imaging module to perform at least one measurement in each environment are response to infrared radiation received in each environment, wherein the measurements are adapted to be used to provide at least one calibration value for each infrared sensor of each infrared imaging module for each of the environments.

9. The apparatus of claim 8, further comprising a plurality of sockets adapted to receive the infrared imaging modules on the conveyor.

10. The apparatus of claim 9, wherein the test equipment is adapted to provide the test signals to the infrared imaging modules through the sockets.

11. The apparatus of claim 8, wherein each infrared imaging module is adapted to store its associated calibration values in a single table.

12. The apparatus of claim 8, wherein the infrared imaging modules are adapted to determine the calibration values based on the measurements.

13. The apparatus of claim 8, further comprising a calibration device adapted to determine the calibration values based on the measurements.

14. The apparatus of claim 8, wherein the conveyor is adapted to continuously transport the infrared imaging modules through the environments.

15. The apparatus of claim 8, wherein the calibration values are non-uniformity correction (NUC) values.

16. The apparatus of claim 8, wherein each temperature controlled environment exhibits a corresponding ambient temperature greater than or less than an associated measurement temperature of the infrared imaging modules to slew current temperatures of the infrared imaging modules to the associated measurement temperature.

17. The apparatus of claim 8, wherein the infrared imaging modules are maintained in the environments for time periods approximately equal to two thirds of a thermal time constant associated with the infrared imaging modules.