Imaging System

• US 20110199578A1
• Filed: 02/14/2011
• Published: 08/18/2011
• Est. Priority Date: 02/18/2010
• Status: Active Grant

• Current Assignee: Raytheon Company (Rtx Corporation)
• Original Assignee: Raytheon Company (Rtx Corporation)
• Inventors: Silver, Alan G., Black, Stephen H., Portnoy, Andrew D.
• Granted Patent: US 8,511,823 B2
• Time in Patent Office: Days
• US Class Current: 351/206
• CPC Class Codes: A61B 3/12 for looking at the eye fundus, e.g. ophthalmoscopes A61B3/13 takes precedence
• CPC Class Codes: H04N 25/40 Extracting pixel data from image sensors by controlling scanning circuits, e.g. by modifying the number of pixels sampled or to be sampled
• CPC Class Codes: H04N 25/443 by reading pixels from selected 2D regions of the array, e.g. for windowing or digital zooming
• CPC Class Codes: H04N 25/445 by skipping some contiguous pixels within the read portion of the array
• CPC Class Codes: H04N 25/702 SSIS architectures characterised by non-identical, non-equidistant or non-planar pixel layout

Abstract

According to certain embodiments, foveal array elements of a foveal region of a focal plane array are sampled at a faster sampling rate to yield foveal array data. Peripheral array elements of a peripheral region of the focal plane array are sampled at a slower sampling rate or sparser sampling density to yield peripheral array data. The foveal array data is processed to yield foveal image data for a foveal region of a display. The peripheral array data is processed to yield peripheral image data for a peripheral region of the display.

Claims

1. A method comprising:

sampling a plurality of foveal array elements of a detector foveal region of a focal plane array at a faster sampling rate to yield foveal array data;

sampling a plurality of peripheral array elements of a detector peripheral region of the focal plane array at a slower sampling rate to yield peripheral array data;

processing the foveal array data to yield foveal image data for a display foveal region of a display; and

processing the peripheral array data to yield peripheral image data for a display peripheral region of the display.

2. The method of claim 1:

the plurality of peripheral array elements comprising a plurality of sub-regions, each sub-region comprising two or more peripheral array elements; and

the sampling the peripheral array elements further comprising sampling a proper subset of each sub-region.

3. The method of claim 1:

the plurality of peripheral array elements comprising a plurality of sub-regions, each sub-region comprising two or more peripheral array elements; and

the sampling the peripheral array elements further comprising performing the following for each sub-region;

sampling a first subset of the each sub-region for a first frame; and

sampling a second subset of the each sub-region for a second frame, the second subset not equal to the first subset.

4. The method of claim 1, the processing the peripheral array data further comprising:

generating first image data generated from a first subset of the peripheral array elements for a first frame and a second frame; and

generating second image data generated from a second subset of the peripheral array elements for the second frame and a third frame.

5. The method of claim 1, the processing the peripheral array data further comprising:

generating first image data generated from a first subset of the peripheral array elements for a first frame; and

holding the first image data for a second frame.

6. The method of claim 1, the processing the peripheral array data further comprising:

generating first image data generated from a first subset of the peripheral array elements for a first frame; and

averaging the first image data with second image data generated from a second subset of the peripheral array elements for a second frame.

7. The method of claim 1, further comprising:

designating a plurality of array elements as the foveal array elements to set the foveal region.

8. The method of claim 1, further comprising setting the foveal region by:

sending one or more fovea start addresses and one or more fovea stop addresses to the focal plane array.

9. The method of claim 1:

the focal plane array comprising a microbolometer array; and

further comprising maintaining a constant bias duty cycle to compensate for an impact of one or more changes in Joule heating in one or more peripheral array elements as a sampling duty cycle changes.

10. The method of claim 1:

the focal plane array comprising a microbolometer array; and

further comprising electronically adjusting one or more bias conditions of the microbolometer to compensate for an impact of one or more changes in Joule heating in one or more peripheral array elements as a sampling duty cycle changes.

11. The method of claim 1:

the focal plane array comprising a microbolometer array; and

further comprising electronically adjusting an operating bias of supporting circuitry of the microbolometer to compensate for an impact of one or more changes in Joule heating in one or more peripheral array elements as a sampling duty cycle changes.

12. A system comprising:

a focal plane array; and

one or more processors operable to;

sample a plurality of foveal array elements of a detector foveal region of the focal plane array at a faster sampling rate to yield foveal array data;

sample a plurality of peripheral array elements of a detector peripheral region of the focal plane array at a slower sampling rate to yield peripheral array data;

process the foveal array data to yield foveal image data for a display foveal region of a display; and

process the peripheral array data to yield peripheral image data for a display peripheral region of the display.

13. The system of claim 12:

the plurality of peripheral array elements comprising a plurality of sub-regions, each sub-region comprising two or more peripheral array elements; and

the sampling the peripheral array elements further comprising sampling a proper subset of each sub-region.

14. The system of claim 12:

the plurality of peripheral array elements comprising a plurality of sub-regions, each sub-region comprising two or more peripheral array elements; and

the sampling the peripheral array elements further comprising performing the following for each sub-region;

sampling a first subset of the each sub-region for a first frame; and

sampling a second subset of the each sub-region for a second frame, the second subset not equal to the first subset.

15. The system of claim 12, the processing the peripheral array data further comprising:

generating first image data generated from a first subset of the peripheral array elements for a first frame and a second frame; and

generating second image data generated from a second subset of the peripheral array elements for the second frame and a third frame.

16. The system of claim 12, the processing the peripheral array data further comprising:

generating first image data generated from a first subset of the peripheral array elements for a first frame; and

holding the first image data for a second frame.

17. The system of claim 12, the processing the peripheral array data further comprising:

generating first image data generated from a first subset of the peripheral array elements for a first frame; and

averaging the first image data with second image data generated from a second subset of the peripheral array elements for a second frame.

18. The system of claim 12, the one or more processors further operable to set the foveal region by:

sending one or more fovea start addresses and one or more fovea stop addresses to the focal plane array.

19. The system of claim 12:

the focal plane array comprising a microbolometer array; and

the one or more processors further operable to maintain a constant bias duty cycle to compensate for an impact of one or more changes in Joule heating in one or more peripheral array elements as a sampling duty cycle changes.

20. The system of claim 12:

the focal plane array comprising a microbolometer array; and

the one or more processors further operable to electronically adjust one or more bias conditions of the microbolometer to compensate for an impact of one or more changes in Joule heating in one or more peripheral array elements as a sampling duty cycle changes.