Optical navigation device with a backlight and associated methods

• US 9,354,747 B2
• Filed: 12/09/2010
• Issued: 05/31/2016
• Est. Priority Date: 12/10/2009
• Status: Active Grant

• Current Assignee: STMicroelectronics Limited (STMicroelectronics NV)
• Original Assignee: STMicroelectronics Limited (STMicroelectronics NV)
• Inventors: Raynor, Jeffrey M.
• Primary Examiner(s): Chang, Kent
• Assistant Examiner(s): Hagemeier, Herbert L
• Application Number:
  US12/964,146
• Publication Number:
  US 20110141487A1
• Time in Patent Office: 2,000 Days
• Field of Search: 345 76-204, 255/208.1, 315/151
• US Class Current: 1/1
• CPC Class Codes: G01C 3/08 Use of electric radiation detectors
• CPC Class Codes: G06F 18/00 Pattern recognition
• CPC Class Codes: G06F 3/042 by opto-electronic means
• CPC Class Codes: H01L 27/14643 Photodiode arrays; MOS imagers
• CPC Class Codes: H10K 59/40 OLEDs integrated with touch screens

Abstract

An optical navigation device includes a navigation radiation source capable of producing a beam of radiation, and an optical element. The optical navigation device is for identifying movement of an object to thereby enable a control action to be carried out. A sensor is for receiving an image based upon reflected radiation from the navigation radiation source, and at least one illumination radiation source is for illuminating the optical navigation device. The device is operable, in recurrent cycles of at least reset, expose, and readout phases, to activate the at least one illumination radiation source during the reset phase. The reset phase may have the longest duration of the phases.

Claims

1. An optical navigation device for operation of an electronic device and operable in recurrent cycles of a reset phase, an expose phase, and a readout phase, the optical navigation device comprising:

a navigation radiation source configured to produce a radiation beam;

an optical element in a path of the radiation beam and having a mousing surface;

a sensor configured to receive images based upon radiation reflected from an adjacent object in the path of the radiation beam as the object is moved across the mousing surface while in direct contact therewith, with movement of the object being translated into actions to operate the electronic device;

at least one illumination source configured to radiate during the reset phase to provide a collimated beam of light at an oblique angle to the mousing surface so as to backlight the mousing surface of said optical element and to not radiate during the expose and readout phase, the reset phase having a longer duration than the expose phase and the readout phase; and

said sensor is configured to be reset to a threshold level during the reset phase, to determine a sensor output level in an absence of light during the calibration phase, to receive the image during the expose phase, and to output the image during the readout phase.

2. An optical navigation device as in claim 1, wherein the duration of the reset phase is at least equal to a sum of durations of the expose phase and the readout phase.

3. An optical navigation device as in claim 1, wherein said at least one illumination source is configured to switch off before an end of the reset phase.

4. An optical navigation device as in claim 1, wherein said at least one illumination source is configured to not activate while said sensor is receiving images indicative of movement of the adjacent object, or while said sensor is receiving images with detectable features.

5. An optical navigation device as in claim 1, wherein said at least one illumination source is configured such that a duration that said at least one illumination source is activated during each reset phase is variable so as to control illumination intensity.

6. An optical navigation device as in claim 5, wherein the duration that said at least one illumination source is configured to be activated during each reset phase does not alter the duration of said reset phase.

7. An optical navigation device as in claim 1, wherein said at least one illumination source is configured to be controllable.

8. An optical navigation device as in claim 1, wherein said at least one illumination source is configured to be dependent upon a device status.

9. An optical navigation device as in claim 1, wherein said at least one illumination source comprises a plurality thereof.

10. An optical navigation device as in claim 9, wherein each of said plurality of illumination sources is configured to illuminate a different portion of said navigation device.

11. An optical navigation device in claim 9, wherein each of said plurality of illumination sources is configured to output a different color of visible light.

12. An optical navigation device as in claim 11, wherein said plurality of illumination sources comprises first, second, and third illumination sources configured to output red, green, and blue light, respectively.

13. An optical navigation device as in claim 11, wherein said plurality of illumination sources is configured such that one of said plurality thereof is on at a given time.

14. An optical navigation device as in claim 11, wherein at least two of said plurality of illumination sources are configured to be turned on during the reset phase, such that a ratio of durations that each illumination source is turned on determines perceived illumination color.

15. An optical navigation device as in claim 14, wherein the ratio of durations is controllable.

16. An optical navigation device as in claim 14 wherein the ratio of durations is based upon a device status.

17. An optical navigation device as in claim 14, wherein the ratio of durations is set proportionally;

and wherein an illumination intensity of said plurality of illumination sources is configurable.

18. An optical navigation device as in claim 11, wherein said plurality of illumination sources is configured to achieve a perceived constant illumination intensity for different colors by adjusting an actual illumination intensity to allow for relative sensitivities of a human eye to different colors.

19. An optical navigation device as in claim 18, wherein said plurality of illumination sources is configured to further adjust for different efficiencies in different color illumination sources to achieve the perceived constant illumination intensity.

20. An optical navigation device as in claim 1, further comprising an ambient light detector;

and wherein said at least one illumination source is configured to be turned off when said ambient light detector is activated.

21. An optical navigation device as in claim 1, wherein said sensor comprises an ambient light detector configured to be activated when said at least one illumination source is turned off.

22. An optical navigation device for operation of an electronic device and operable in a reset phase, an expose phase, and a readout phase, the optical navigation device comprising

a navigation radiation source configured to produce a radiation beam;

an optical element in a path of the radiation beam and having a mousing surface;

a sensor configured to receive images based upon radiation reflected from an adjacent object in the path of the radiation beam as the object is moved across the mousing surface while in direct contact therewith, with movement of the object being translated into actions to operate the electronic device; and

at least one illumination source configured to radiate during the reset phase to provide a collimated beam of light at an oblique angle to the mousing surface so as to backlight the mousing surface of said optical element and to not radiate during the expose and readout phase, a duration of the reset phase being at least equal to a sum of durations of the expose phase and the readout phase;

said sensor is configured to be reset to a threshold level during the reset phase, to determine a sensor output level in an absence of light during the calibration phase, to receive the image during the expose phase, and to output the image during the readout phase.

23. An optical navigation device as in claim 22, wherein said at least one illumination source is configured to switch off before an end of the reset phase.

24. An optical navigation device as in claim 22, wherein said at least one illumination source is configured to not activate while said sensor is receiving images indicative of movement of the adjacent object, or while said sensor is receiving images with detectable features.

25. An optical navigation device as in claim 22, wherein said at least one illumination source is configured such that a duration that said at least one illumination source is activated during each reset phase is variable so as to control illumination intensity.

26. A method of controlling illumination of an optical navigation device for operation of an electronic device and operable in recurrent cycles of a reset phase, an expose phase, and a readout phase, the method comprising:

producing a radiation beam using a navigation radiation source, with an optical element in a path of the radiation beam and having a mousing surface;

receiving at a sensor images based upon radiation reflected from an adjacent object in the path of the radiation beam as the object is moved across the mousing surface while in direct contact therewith, with movement of the object being translated into actions to operate the electronic device;

radiating from at least one illumination source during the reset phase to provide a collimated beam of light at an oblique angle to the mousing surface so as to backlight the mousing surface of the optical element and to not radiate during the expose and readout phase, the reset phase having a longer duration than the expose phase and the readout phase;

the sensor is configured to be reset to a threshold level during the reset phase, to determine a sensor output level in an absence of light during the calibration phase, to receive the image during the expose phase, and to output the image during the readout phase; and

identifying movement of the adjacent object to thereby enable a control action to be carried out.

28. A method as in claim 26, wherein the at least one illumination source is not activated while the sensor is receiving images indicative of movement of the adjacent object, or while the sensor is receiving images with detectable features.

29. A method as in claim 26, wherein a duration that the at least one illumination source is activated during each reset phase is variable so as to control illumination intensity.

30. A method as in claim 29 wherein the duration that the at least one illumination source is configured to be activated during each reset phase does not alter the duration of the reset phase.

31. A method as in claim 26, wherein the illumination source is selectably controllable.

32. A method as in claim 26, wherein the at least one illumination source is configured to be dependent upon a device status.

33. A method as in claim 26, wherein the at least one illumination source comprises a plurality thereof.

34. A method as in claim 33, wherein each of the plurality of illumination sources illuminates a different portion of the navigation device.

35. A method as in claim 33, wherein each of the plurality of illumination sources outputs a different color of visible light.

36. A method as in claim 35, wherein the plurality of illumination sources comprises first, second, and third illumination sources configured to output red, green, and blue light, respectively.

37. A method as in claim 35, wherein the plurality of illumination sources is configured such that one of the plurality thereof is on at a given time.

38. A method as in claim 35, wherein at least two of the plurality of illumination sources are turned on during the reset phase, such that a ratio of durations that each illumination source is turned on determines perceived illumination color.

39. A method as in claim 38, wherein the ratio of durations is selectably controllable.

40. A method as in claim 38, wherein the ratio of durations is based upon a status of the navigation device.

41. A method as in claim 38, wherein the ratio of durations is set proportionally;

and wherein an illumination intensity of the plurality of illumination sources is selectably configurable.

42. A method as in claim 33, wherein the plurality of illumination sources achieves a perceived constant illumination intensity for different colors by adjusting an actual illumination intensity to allow for relative sensitivities of a human eye to different colors.

43. A method as in claim 42, wherein the plurality of illumination sources further adjusts for different efficiencies in different color illumination sources to achieve the perceived constant illumination intensity.

44. A method as in claim 26, wherein the illumination source is to be turned off when an ambient light detector is activated.

27. a method as in clam 26, wherein the duration of the reset phase is at least equal to a sum of durations of the expose phase and the readout phase;

and

wherein the illumination source is switched off before an end of the reset phase.

45. An electronic device comprising:

an optical navigation device operable in recurrent cycles of a reset phase, an expose phase, and a readout phase, said optical navigation device comprising

a navigation radiation source configured to produce a radiation beam,

an optical element in a path of the radiation beam and having a mousing surface,

a sensor configured to receive images based upon radiation reflected from an adjacent object in the path of the radiation beam as the object is moved across the mousing surface while in direct contact therewith, with movement of the object being translated into actions to operate the electronic device,

at least one illumination source configured to radiate during the reset phase to provide a collimated beam of light at an oblique angle to the mousing surface so as to backlight the mousing surface of said optical element and to not radiate during the expose and readout phase, the reset phase having a longer duration than the expose phase and the readout phase, and

said sensor is configured to be reset to a threshold level during the reset phase, to determine a sensor output level in an absence of light during the calibration phase, to receive the image during the expose phase, and to output the image during the readout phase.

46. An electronic device as in claim 45, wherein the electronic device comprises a mobile computing device.

47. An electronic device as in claim 45, wherein the electronic device comprises a mobile telecommunications device.

48. An electronic device as in claim 45, wherein the electronic device comprises a remote control device.