Dual color/dual function focal plane

• US 8,153,978 B1
• Filed: 03/08/2007
• Issued: 04/10/2012
• Est. Priority Date: 03/08/2006
• Status: Active Grant

• Current Assignee: Oceanit Laboratories, Inc.
• Original Assignee: Oceanit Laboratories, Inc.
• Inventors: Wolfshagen, Randy, Scott, Basil
• Primary Examiner(s): Porta, David
• Assistant Examiner(s): Bryant, Casey
• Application Number:
  US11/715,617
• Time in Patent Office: 1,860 Days
• Field of Search: 250/338.1, 250/339.01, 250/339.02, 250/339.14, 250/342
• US Class Current: 250/339.02
• CPC Class Codes: F41G 7/008 Combinations of different guidance systems
• CPC Class Codes: F41G 7/2253 Passive homing systems, i.e. comprising a receiver and do not requiring an active illumination of the target
• CPC Class Codes: F41G 7/2293 using electromagnetic waves other than radio waves
• CPC Class Codes: G01J 3/36 Investigating two or more bands of a spectrum by separate detectors
• CPC Class Codes: G01S 3/784 using a mosaic of detectors
• CPC Class Codes: H04N 23/11 for generating image signals from visible and infrared light wavelengths

Abstract

A single focal plane integrated circuit hybrid replaces multiple focal plane circuits and associated off-focal plane signal processing electronics. A dual function, dual color focal plane PSD sensor chip assembly includes a PSD array, a traditional pixelized camera array, a signal processing chip, and flip-chip interconnects and wirebond pads to support electronics on the signal processing chip. The camera array is made of a material sensitive to wavelengths longer than the PSD array material is sensitive to. The PSD array is disposed in the same substrate as the camera array. The PSD array tracks object locations and directs the camera array to window and zoom while capturing images. Inherent registration of PSD cells to the pixelized camera array makes responsivity map testing and spatial calibration unnecessary. Reduction in power dissipation is achieved by powering on the camera array only when the PSD detects a change in scene.

Claims

1. A dual function, dual color focal plane PSD sensor chip assembly, comprising:

a position sensitive wavefront sensor array,

a pixelized camera array made of semiconductor material,

a signal processing chip,

flip-chip interconnects on the signal processing chip, and

wirebond pads on the signal processing chip to support electronics,

wherein short wavelength infrared photons are absorbed by the position sensitive wavefront sensor array and long wavelength infrared photons are absorbed by the camera array, and

wherein the position sensitive wavefront sensor array is configured to permit long wavelength infrared photons to pass through the position sensitive wavefront sensor array to be absorbed by the pixelized camera array.

2. The sensor chip assembly of claim 1, wherein the position sensitive wavefront sensor array is made of visible, short, mid, and long wavelength sensitive material.

3. The sensor chip assembly of claim 1, wherein the position sensitive wavefront sensor array is disposed in a same substrate as the camera array.

4. The sensor chip assembly of claim 3, wherein the substrate is HgCdTe.

5. The sensor chip assembly of claim 1, wherein the camera array comprises pixels made from a long wave infrared sensitive layer.

6. The sensor chip assembly of claim 1, wherein the camera array is made of a material sensitive to wavelengths longer than the position sensitive wavefront sensor array is sensitive to.

7. The sensor chip assembly of claim 1, wherein the flip-chip interconnects are indium bumps.

8. The sensor chip assembly of claim 1, further comprising a camera control mechanism, wherein the camera control mechanism uses the position sensitive wavefront sensor array'"'"'s calculation of object location to instruct the camera array to window and zoom, allowing production of images that accurately track objects automatically without any control from off the sensor chip assembly.

9. The sensor chip assembly of claim 1, wherein the position sensitive wavefront sensor array has cells and pixels of the camera array are directly below the cells of the position sensitive wavefront sensor array, creating inherent registration of the position sensitive wavefront sensor cells and eliminating the need for a mechanism to perform responsivity map testing and calibration.

10. The sensor chip assembly of claim 1, further comprising a signal mechanism, wherein the position sensitive wavefront sensor array uses the signal mechanism to signal the camera array to power up when it detects an appropriate change of scene.

11. A method of using the sensor chip assembly of claim 1, comprising using the position sensitive wavefront sensor array to track objects while using the camera array to capture images.

12. The method of claim 11, wherein the images are used to perform special discrimination functions.

13. A method of using the sensor chip assembly of claim 1, comprising using a calculation of object location by the position sensitive wavefront sensor array to instruct the camera array to window and zoom, producing images that accurately track objects automatically, without any control from off the sensor chip assembly.

14. A method of using the sensor chip assembly of claim 1, comprising placing position sensitive wavefront sensor cells of the position sensitive wavefront sensor array directly above camera array pixels, inherently registering the position sensitive wavefront sensor cells, eliminating responsivity map testing and spatial calibration requirements.

15. A method of using the sensor chip assembly of claim 1, comprising letting the position sensitive wavefront sensor array signal the camera array to power up only when the position sensitive wavefront sensor array detects an appropriate change of scene.