Low power and small form factor infrared imaging

• US 9,716,844 B2
• Filed: 12/18/2013
• Issued: 07/25/2017
• 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: Hoelter, Theodore R., Boulanger, Pierre, Sharp, Barbara, Nussmeier, Mark, Kurth, Eric A., Hgasten, Nicholas, Strandemar, Katrin
• Primary Examiner(s): Kim, Kiho
• Application Number:
  US14/133,095
• Publication Number:
  US 20160366345A1
• Time in Patent Office: 1,315 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 constructional features concerning the integration of cameras in portable phones H04M1/0264
• 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 25/60 Noise processing, e.g. detecting, correcting, reducing or removing noise
• CPC Class Codes: H04N 25/75 Circuitry for providing, modifying or processing image signals from the pixel array
• 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, especially for low power and small form factor applications. In one example, a system includes a focal plane array (FPA). The FPA includes an array of infrared sensors adapted to image a scene. A low-dropout regulator (LDO) is integrated with the FPA and adapted to provide a regulated voltage in response to an external supply voltage. The FPA also includes a bias circuit adapted to provide a bias voltage to the infrared sensors in response to the regulated voltage. 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 sensor assembly implemented as a focal plane array (FPA) comprising;

a low-dropout regulator (LDO) adapted to provide a regulated voltage in response to an external supply voltage;

an array of infrared sensors adapted to image a scene;

a bias circuit connected to the LDO, the bias circuit adapted to provide an adjustable bias voltage to the array of infrared sensors in response to the regulated voltage;

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

wherein the LDO, the array of infrared sensors, the bias circuit, and the ROIC are integrated together using a shared substrate.

2. The system of claim 1, wherein the FPA is powered by only the external supply voltage.

3. The system of claim 2, further comprising:

a multiplexer;

an output amplifier; and

wherein the LDO is adapted to provide the regulated voltage to the multiplexer and the output amplifier.

4. The system of claim 2, further comprising a battery external to the FPA and adapted to provide the external supply voltage.

5. The system of claim 1, wherein the bias circuit is a bias correction circuit adapted to adjust the bias voltage to compensate for temperature-dependent changes and/or self-heating.

6. The system of claim 1, wherein the FPA is a wafer level package.

7. The system of claim 1, wherein the system is a mobile telephone.

8. The system of claim 1, wherein the system is an infrared camera, the system further comprising a housing adapted to substantially enclose the FPA.

9. The system of claim 8, further comprising a processor adapted to receive the captured image frames and provide the captured image frames with reduced noise in response thereto.

10. The system of claim 1, further comprising a processor adapted to process an intentionally blurred one of the captured image frames, wherein the blurred image frame comprises blurred theiinal 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) tennis to reduce at least a portion of the noise; and

apply the NUC terms to the captured image frames.

11. A method comprising:

receiving an external supply voltage at a sensor assembly implemented as a focal plane array (FPA);

providing a regulated voltage in response to the external supply voltage using a low-dropout regulator (LDO);

providing an adjustable bias voltage to an array of infrared sensors of the FPA in response to the regulated voltage using a bias circuit of the FPA, wherein the bias circuit is connected to the LDO;

imaging a scene using the infrared sensors;

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

wherein the LDO, the array of infrared sensors, the bias circuit, and the ROIC are integrated together using a shared substrate.

12. The method of claim 11, wherein the FPA is powered by only the external supply voltage.

13. The method of claim 12, further comprising providing the regulated voltage to a multiplexer and an output amplifier of the FPA.

14. The method of claim 12, further comprising providing the external supply voltage from a battery external to the FPA.

15. The method of claim 11, wherein the bias circuit is a bias correction circuit, the method further comprising adjusting the bias voltage using the bias correction circuit to compensate for temperature-dependent changes and/or self-heating.

16. The method of claim 11, wherein the FPA is a wafer level package.

17. The method of claim 11, wherein the method is performed by an infrared imaging module of a mobile telephone.

18. The method of claim 11, wherein the method is performed by an infrared camera comprising a housing adapted to substantially enclose the FPA.

19. The method of claim 18, further comprising processing the captured image frames to provide resulting image frames with reduced noise.

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.