Low power and small form factor infrared imaging

• US 9,706,139 B2
• Filed: 12/09/2013
• Issued: 07/11/2017
• 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: Nussmeier, Mark, Kurth, Eric A., Hgasten, Nicholas, Hoelter, Theodore R., Strandemar, Katrin, Boulanger, Pierre, Sharp, Barbara
• Primary Examiner(s): Rao, Andy
• Assistant Examiner(s): Edwards, Tyler
• Application Number:
  US14/101,245
• Publication Number:
  US 20140139685A1
• Time in Patent Office: 1,310 Days
• CPC Class Codes: H04M 1/725 Cordless telephones user interfaces specially adapted therefor H04M1/724
• CPC Class Codes: H04M 2250/52 including functional features of a camera
• CPC Class Codes: H04N 23/51 Housings
• 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 25/21 for transforming thermal infrared radiation into image signals
• CPC Class Codes: H04N 25/60 Noise processing, e.g. detecting, correcting, reducing or removing noise
• CPC Class Codes: H04N 25/673 by using reference sources
• CPC Class Codes: H04N 25/75 Circuitry for providing, modifying or processing image signals from the pixel array
• CPC Class Codes: H04N 25/78 Readout circuits for addressed sensors, e.g. output amplifiers or A/D converters
• 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

Abstract

Various techniques are provided for implementing an infrared imaging system. In one example, a system includes a focal plane array (FPA). The FPA includes an array of infrared sensors adapted to image a scene. The FPA also includes a bias circuit adapted to provide a bias voltage to the infrared sensors. The bias voltage is selected from a range of approximately 0.2 volts to approximately 0.7 volts. The FPA also includes a read out integrated circuit (ROIC) adapted to provide signals from the infrared sensors corresponding to captured image frames. Other implementations are also provided.

Claims

1. A system comprising:

a focal plane array (FPA) comprising;

an array of infrared sensors adapted to image a scene;

a bias circuit adapted to provide a bias voltage to the infrared sensors, wherein the bias voltage is selected from a range of approximately 0.2 volts to approximately 0.7 volts; and

a read out integrated circuit (ROIC) adapted to provide signals from the infrared sensors corresponding to captured image frames.

2. The system of claim 1, wherein a size of the array of infrared sensors is less than approximately 160 by 120.

3. The system of claim 2, wherein the size is one of 80 by 64, 80 by 60, 64 by 64, 64 by 32, or 32 by 32.

4. The system of claim 1, wherein the ROIC is adapted to provide the captured image frames at a frame rate selected from a range of approximately 120 Hz to approximately 480 Hz.

5. The system of claim 4, wherein:

the frame rate is a first frame rate; and

the system further comprises a processor adapted to combine at least a subset of the captured image frames to provide processed image frames at a second frame rate selected from a range of approximately 30 Hz to approximately 60 Hz with reduced noise in comparison with the captured image frames.

6. The system of claim 1, wherein the bias circuit is adapted to provide the bias voltage to the infrared sensors in response to a regulated voltage selected from a range of approximately 1.5 volts to approximately 2.8 volts.

7. The system of claim 6, further comprising a low-dropout regulator (LDO) integrated with the FPA and adapted to provide the regulated voltage to the bias circuit in response to an external supply voltage selected from a range of approximately 2.8 volts to approximately 11 volts.

8. The system of claim 1, wherein the FPA is a first FPA, wherein the array of infrared sensors is a first array, the system further comprising a second FPA comprising a second array of infrared sensors adapted to image the scene.

9. The system of claim 1, wherein the system is an infrared imaging module adapted to be inserted into a socket having a size less than approximately 8.5 mm by 8.5 mm.

10. The system of claim 1, further comprising a processor adapted to process an intentionally blurred image frame, wherein the blurred image frame comprises blurred thermal image data associated with the scene and noise introduced by the system, wherein the processor is adapted to:

use the blurred image frame to determine a plurality of non-uniformity correction (NUC) terms to reduce at least a portion of the noise; and

apply the NUC terms to the captured image frames.

11. A method comprising:

providing a bias voltage from a bias circuit of a focal plane array (FPA) to an array of infrared sensors of the FPA, wherein the bias voltage is selected from a range of approximately 0.2 volts to approximately 0.7 volts;

imaging a scene using the infrared sensors; and

providing signals from the infrared sensors corresponding to captured image frames of the scene using a read out integrated circuit (ROIC) of the FPA.

12. The method of claim 11, wherein a size of the array of infrared sensors is less than approximately 160 by 120.

13. The method of claim 12, wherein the size is one of 80 by 64, 80 by 60, 64 by 64, 64 by 32, or 32 by 32.

14. The method of claim 11, wherein the captured image frames are provided at a frame rate selected from a range of approximately 120 Hz to approximately 480 Hz.

15. The method of claim 14, wherein:

the frame rate is a first frame rate; and

the method further comprises combining at least a subset of the captured image frames to provide processed image frames at a second frame rate selected from a range of approximately 30 Hz to approximately 60 Hz with reduced noise in comparison with the captured image frames.

16. The method of claim 11, further comprising receiving a regulated voltage at the bias circuit selected from a range of approximately 1.5 volts to approximately 2.8 volts, wherein the bias voltage is provided from the bias circuit to the infrared sensors in response to the regulated voltage.

17. The method of claim 16, further comprising providing the regulated voltage from a low-dropout regulator (LDO) integrated with the FPA to the bias circuit in response to an external supply voltage selected from a range of approximately 2.8 volts to approximately 11 volts.

18. The method of claim 11, wherein the FPA is a first FPA, wherein the array of infrared sensors is a first array, the method further comprising imaging the scene using a second FPA comprising a second array of infrared sensors.

19. The method of claim 11, wherein the FPA is part of an infrared imaging module adapted to be inserted into a socket having a size less than approximately 8.5 mm by 8.5 mm.

20. The method of claim 11, further comprising:

receiving an intentionally blurred one of the captured image frames, wherein the blurred image frame comprises blurred thermal image data associated with the scene and noise introduced by an infrared imaging system;

processing the blurred image frame to determine a plurality of non-uniformity correction (NUC) terms to reduce at least a portion of the noise; and

applying the NUC terms to the captured image frames.