METHOD AND ARRANGEMENT FOR TRACKING MOVEMENT RELATIVE TO A SURFACE

• US 20110141022A1
• Filed: 02/24/2011
• Published: 06/16/2011
• Est. Priority Date: 10/06/1995
• Status: Active Grant

• Current Assignee: PixArt Imaging Incorporated
• Original Assignee: Avago Technologies ECBU IP Singapore Pte Limited (Broadcom, Inc.)
• Inventors: Gordon, Gary B., Hartlove, Jason T., Badyal, Rajeev, Knee, Derek L.
• Granted Patent: US 8,350,812 B2
• Time in Patent Office: Days
• US Class Current: 345/166
• CPC Class Codes: G06F 3/0317 in co-operation with a patterned surface, e.g. absolute position or relative movement detection for an optical mouse or pen positioned with respect to a coded surface
• CPC Class Codes: G06F 3/033 Pointing devices displaced or positioned by the user , e.g. mice, trackballs, pens or joysticks; Accessories therefor digitisers characterised by the transducing means G06F3/041
• CPC Class Codes: G06F 3/0346 with detection of the device orientation or free movement in a 3D space, e.g. 3D mice, 6-DOF [six degrees of freedom] pointers using gyroscopes, accelerometers or tilt-sensors
• CPC Class Codes: G06F 3/03543 Mice or pucks G06F3/03541 takes precedence
• CPC Class Codes: G06F 3/038 Control and interface arrangements therefor, e.g. drivers or device-embedded control circuitry

Abstract

In an embodiment, a method of tracking movement relative to a surface involves comparing at least some data elements of a first array with at least some of data elements of a second array if it is determined, from an examination of the first array of data elements, that a characteristic condition does not exist in the first array of data elements, wherein the characteristic condition is related to the uniformity of at least a majority of the data elements of the first array.

Claims

1-12. -12. (canceled)

13. A method of tracking movement relative to a surface, comprising:

providing a source of non-coherent light for illuminating a surface at a low angle of incidence;

providing a two dimensional array of photo detectors for producing arrays of data elements responsive to light reflected from surface irregularities on the illuminated surface; and

providing circuitry

for capturing a first array of data elements from the two dimensional array of photo detectors at a first time,

for examining the first array of data elements to determine whether or not a characteristic condition exists in the first array of data elements;

for capturing a second array of data elements from the two dimensional array of photo detectors at a second time, and

for tracking movement relative to the surface by comparing at least some of the data elements of the first array with at least some of the data elements of the second array if it is determined, from the examination of the first array of data elements, that the characteristic condition does not exist in the first array of data elements, wherein the characteristic condition is related to the uniformity of at least a majority of the data elements of the first array.

14. The invention of claim 13, wherein providing the circuitry further comprises:

providing circuitry

for capturing a third array of data elements from the two dimensional array of photo detectors at a third time if the characteristic condition is detected in the first array, and

for tracking movement relative to the surface by comparing at least some of the data elements of the second array with at least some of the data elements of the third array.

15. The invention of claims 13 or 14 wherein the angle of incidence is a grazing angle.

16. The invention of claims 13 or 14 wherein the angle of incidence is between about 5°

and about 20°

.

17. The invention of claims 13 or 14 wherein providing the circuitry further comprises:

providing circuitry for

capturing a fourth array of data elements from the two dimensional array of photo detectors at a fourth time if the characteristic condition is not detected in the data elements of the first array, and then

tracking movement relative to the surface by comparing at least some of the data elements of the first array with at least some of the data elements of the fourth array.

18. A method of tracking movement, comprising:

providing a source of non-coherent light for illuminating a surface at a low angle of incidence;

providing a two dimensional array of photo detectors responsive to light reflected from features on the illuminated surface; and

providing circuitry for tracking movement relative to the surface by comparing light reflected from the features at a first time with light reflected there from at a second time unless it is determined by an examination of an array of data elements produced in response to the light reflected at the first time that light detected by at least a majority of the photo detectors at the first time is at least nearly uniform.

20. The invention of claims 18 or 19 wherein providing circuitry further comprises:

providing circuitry for thereafter tracking movement relative to the surface by comparing light reflected from the features at the first time with light reflected there from at a third time if movement was tracked by comparing light reflected at the first time with light reflected at the second time.

21. The invention of claims 18 or 19 wherein providing circuitry further comprises:

providing circuitry for thereafter tracking movement relative to the surface by comparing light reflected from the features at the second time with light reflected there from at a third time if movement was not tracked by comparing light reflected at the first time with light reflected at the second time.

22. The invention of claims 18 or 19 wherein the angle of incidence is between about 5°

and about 20°

.

19. A method of tracking movement relative to a surface, comprising:

providing a source of non-coherent light for illuminating a surface at a low angle of incidence;

providing a two dimensional array of photo detectors responsive to light reflected from features located on the illuminated surface; and

providing circuitry for tracking movement relative to the surface by comparing light reflected from the features located on the surface at a first time with light reflected there from at a second time unless it is determined by an examination of an array of data elements produced in response to the light reflected at the first time that light detected by the photo detectors at the first time does not represent a focused image of at least some of the features located on the surface.

23. A method of tracking movement, comprising:

providing a source of non-coherent light for illuminating a surface at a low angle of incidence;

providing a two dimensional array of photo detectors for producing arrays of data elements responsive to light reflected from surface irregularities on the illuminated surface; and

providing circuitry

for capturing a first array of data elements from the two dimensional array of photo detectors at a first time,

for examining the first array of data elements to determine whether or not a characteristic condition exists in the first array of data elements;

for capturing a second array of data elements from the two dimensional array of photo detectors at a second time, and

for tracking movement relative to the surface by comparing at least some of the data elements of the first array with at least some of the data elements of the second array if it is determined, from the examination of the first array of data elements, that the characteristic condition does not exist in the first array of data elements, wherein the characteristic condition is related to a representation of a focused image in the data elements of the first array.

24. The invention of claim 23, wherein providing the circuitry further comprises:

providing circuitry

for capturing a third array of data elements from the two dimensional array of photo detectors at a third time if the characteristic condition is detected in the first array, and

for tracking movement relative to the surface by comparing at least some of the data elements of the second array with at least some of the data elements of the third array.

25. An imaging and navigation arrangement, comprising:

a source of non-coherent light for illuminating a surface at a low angle of incidence;

a two dimensional array of photo detectors for producing arrays of data elements responsive to light reflected from surface irregularities on the illuminated surface; and

circuitry

for capturing a first array of data elements from the two dimensional array of photo detectors at a first time,

for examining the first array of data elements to determine whether or not a characteristic condition exists in the first array of data elements;

for capturing a second array of data elements from the two dimensional array of photo detectors at a second time, and

for tracking movement relative to the surface by comparing at least some of the data elements of the first array with at least some of the data elements of the second array if it is determined, from the examination of the first array of data elements, that the characteristic condition does not exist in the first array of data elements, wherein the characteristic condition is related to the uniformity of at least a majority of the data elements of the first array.

26. An imaging and navigation arrangement, comprising:

a source of non-coherent light for illuminating a surface at a low angle of incidence;

a two dimensional array of photo detectors responsive to light reflected from features on the illuminated surface; and

circuitry for tracking movement relative to the surface by comparing light reflected from the features at a first time with light reflected there from at a second time unless it is determined by an examination of an array of data elements produced in response to the light reflected at the first time that light detected by at least a majority of the photo detectors at the first time is at least nearly uniform.

27. An imaging and navigation arrangement, comprising:

a source of non-coherent light for illuminating a surface at a low angle of incidence;

a two dimensional array of photo detectors responsive to light reflected from features located on the illuminated surface; and

circuitry for tracking movement relative to the surface by comparing light reflected from the features located on the surface at a first time with light reflected there from at a second time unless it is determined by an examination of an array of data elements produced in response to the light reflected at the first time that light detected by the photo detectors at the first time does not represent a focused image of at least some of the features located on the surface.

28. An imaging and navigation arrangement, comprising:

a source of non-coherent light for illuminating a surface at a low angle of incidence;

a two dimensional array of photo detectors for producing arrays of data elements responsive to light reflected from surface irregularities on the illuminated surface; and

circuitry

for capturing a first array of data elements from the two dimensional array of photo detectors at a first time,

for examining the first array of data elements to determine whether or not a characteristic condition exists in the first array of data elements;

for capturing a second array of data elements from the two dimensional array of photo detectors at a second time, and

for tracking movement relative to the surface by comparing at least some of the data elements of the first array with at least some of the data elements of the second array if it is determined, from the examination of the first array of data elements, that the characteristic condition does not exist in the first array of data elements, wherein the characteristic condition is related to a representation of a focused image in the data elements of the first array.