CMOS digital optical navigation chip

• US 6,631,218 B2
• Filed: 01/09/2001
• Issued: 10/07/2003
• Est. Priority Date: 03/18/1998
• Status: Expired due to Fees

• Current Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Original Assignee: Agilent Technologies, Inc., HP Inc.
• Inventors: Badyal, Rajeev, Knee, Derek L., Misek, Brian James, Anderson, Mark Alan
• Primary Examiner(s): Mehta, Bhavesh M.
• Assistant Examiner(s): Kassa, Yosef
• Application Number:
  US09/756,817
• Publication Number:
  US 20010012408A1
• Time in Patent Office: 1,001 Days
• Field of Search: 382/307, 382/144, 382/209, 382/210, 382/217, 382/218, 382/219, 382/224, 382/278, 382/305, 257/74, 257/84, 257/133, 257/140, 257/265, 257/334
• US Class Current: 382/307
• CPC Class Codes: H04N 23/68 for stable pick-up of the scene, e.g. compensating for camera body vibrations
• CPC Class Codes: H04N 25/00 Circuitry of solid-state image sensors [SSIS]; Control thereof
• 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 25/76 Addressed sensors, e.g. MOS or CMOS sensors
• CPC Class Codes: H04N 3/155 Control of the image-sensor operation, e.g. image processing within the image-sensor

Abstract

A CMOS digital integrated circuit digitally captures an image, generates a result surface on which a minima resides, and compares the result surfaces. The correlation of the result surfaces represents a best fit image displacement between image frames.

Claims

1. An integrated circuit chip for capturing and processing images, comprising:

imaging circuitry for capturing an image projected thereon and for generating an analog signal representative thereof;

conversion circuitry for converting the analog signal to a corresponding digital signal;

correlation circuitry for processing the digital signal to generate a result surface on which a minimum resides, the minimum representing a best fit image displacement between the captured image and previous ones thereof;

comparison circuitry for comparing the result surfaces and generating a navigation signal; and

interface circuitry for formatting the navigation signal so as to be compatible for signal communication with a preselected device.

2. The chip of claim 1 further comprising:

filter circuitry for enhancing edges of the image represented by the digital signal.

3. The chip of claim 1 further comprising:

filter circuitry for enhancing contrast of the image represented by the digital signal.

4. The chip of claim 1 further comprising:

interpolation circuitry for mapping the image as represented by the result surface into spatially-defining coordinates.

5. The chip of claim 1 in which the imaging circuitry includes a photo cell array.

6. The chip of claim 5 in which each photo cell has a programmable shutter speed.

7. The chip of claim 5 in which the imaging circuitry includes transfer amplifier circuitry for converting output from the photo cell array into the analog signal.

8. The chip of claim 5 in which the regions of the photo cell array are selectable to be active in operation of the imaging circuitry.

9. The chip of claim 1 in which the filter circuitry includes a spatial filter.

10. The chip of claim 1 further comprising compression circuitry for reducing storage needs of the digital signal.

11. A method for capturing and processing images on a unitary integrated circuit chip, comprising the steps of:

(a) capturing an image and generating an analog signal representative thereof;

(b) converting the analog signal to a cones ding digital signal;

(c) processing the digital signal to generate a result surface on which a minimum resides, the minimum representing a best fit image displacement between the captured image and previous ones thereof;

(d) mapping the image as represented by the result surface into spatially-defining coordinates;

(e) comparing the images and generating a navigation signal;

(f) formatting the navigation signal so as to be compatible for signal communication with a preselected device.

12. The method of claim 11 further comprising the step of:

(f) between steps (b) and (c), enhancing at least one quality of the image represented by the digital signal with a spatial filter, said quality selected from the group consisting of;

(i) edges; and

(ii) contrast.

13. The method of claim 11 further comprising the step of:

(f) between steps (b) and (c), compressing the digital signal.

14. A unitary integrated circuit chip for capturing and processing images, comprising

means for capturing an image and generating an analog signal representative thereof;

means for converting the analog signal to a corresponding digital signal;

means for enhancing at least one quality of the image represented by the digital signal with a spatial filter, said quality selected from the group consisting of;

(i) edges; and

(ii) contrast;

means for processing the digital signal to generate a result surface on which a minimum resides, the minimum representing a best fit image displacement between the captured image and previous ones thereof;

means for comparing the result surfaces and generating a navigation signal; and

means for formatting the navigation signal so to be compatible for signal communication wit a preselected device.

15. The chip of claim 14 further comprising:

means for mapping the image as represented by the result surface into spatially-defining coordinates.

16. The chip of claim 14 further comprising:

means responsive to the means for enhancing, or compressing the digital signal.

17. The chip of claim 14 in which the means for imaging includes a photo cell array having a preselected number of photo transistors.

18. The chip of claim 17 in which each photo cell in said array has a programmable shutter speed.

19. The chip of claim 17 in which the means for imaging includes transfer amplifier circuitry for converting output from the photo cell array into the analog signal.

20. The chip of claim 19 in which the regions of the photo cell array are selectable to be active in operation of the means for imaging.