Integrated photonics module and devices using integrated photonics modules

• US 20070273794A1
• Filed: 04/10/2007
• Published: 11/29/2007
• Est. Priority Date: 04/11/2006
• Status: Active Grant

• Current Assignee: Microvision, Inc.
• Original Assignee: Microvision, Inc.
• Inventors: Xue, Bin, Niesten, Maarten, Freeman, Mark, Sprague, Randall, Brown, Margaret, Miller, Joshua, Wiklof, Christopher
• Granted Patent: US 7,834,867 B2
• Time in Patent Office: Days
• US Class Current: 348/744
• CPC Class Codes: G02B 27/104 for use with scanning systems scanning systems G02B26/10
• CPC Class Codes: G02B 27/1066 for enhancing image performance, like resolution, pixel numbers, dual magnifications or dynamic range, by tiling, slicing or overlapping fields of view
• CPC Class Codes: G02B 27/141 using dichroic mirrors
• CPC Class Codes: G02B 27/145 having sequential partially reflecting surfaces
• CPC Class Codes: G02B 27/283 used for beam splitting or combining
• CPC Class Codes: G09G 3/025 with scanning or deflecting the beams in two directions or dimensions
• CPC Class Codes: G09G 3/346 based on modulation of the reflection angle, e.g. micromirrors micromirrors devices per se G02B26/0833
• CPC Class Codes: H04N 9/3111 for displaying the colours sequentially, e.g. by using sequentially activated light sources sequential projection in colour photography G03B33/08
• CPC Class Codes: H04N 9/3129 scanning a light beam on the display screen scanning a light beam on a screen in displays other than projection devices G09G3/02; scanning systems in general G02B26/10; projectors using laser light sources in general H04N9/3161

Abstract

An integrated photonics module includes at least one light source and a MEMS scanner coupled to and held in alignment by an optical frame configured for mounting to a host system. According to some embodiments, the integrated photonics module may include a plurality of light sources and a beam combiner coupled to the optical frame. According to some embodiments, the integrated photonics module includes a selective fold mirror configured to direct at least a portion of emitted light toward the MEMS scanner in a normal direction and pass scanned light through to a field of view. The selective fold mirror may use beam polarization to select beam passing and reflection. The integrated photonics module may include a beam rotator such as a quarter-wave plate to convert the polarization of the emitted light to a different polarization adapted for passage through the fold mirror. The integrated photonics module may include one or more light detectors.

Claims

1. An integrated photonics module suitable for integration in an electronic apparatus comprising:

a first alignment frame;

a modulatable red laser diode mounted to the first alignment frame and operable to emit a modulated beam of red light along a first axis;

a modulatable green SHG laser mounted to the first alignment frame and operable to emit a beam of modulated green light along a second axis parallel to the first axis;

a modulatable blue laser diode mounted to the first alignment frame and operable to emit a modulated beam of blue light along a third axis parallel to the first and second axes;

a beam combiner mounted to the first alignment frame and aligned to receive the modulated beams of red, green and blue light and combine the received beams into a modulated composite beam and launch the composite beam along a fourth axis;

a beam scanner mounted to the first alignment frame, aligned to receive the composite beam along a fifth axis, and operable to deflect the composite beam as a modulated scanned beam in a periodic scan pattern.

2. The integrated photonics module of claim 1 further comprising:

a selective reflector aligned to receive the modulated composite beam and the modulated scanned beam and allow at least a portion of the modulated scanned beam to pass toward a field of view.

3. The integrated photonics module of claim 2 wherein the selective reflector includes a partial reflector.

4. The integrated photonics module of claim 2 wherein the selective reflector is configured to receive the modulated composite beam along the fourth axis and deflect at least a portion of it along the fifth axis, wherein the fifth axis is not parallel to the fourth axis.

5. The integrated photonics module of claim 4 wherein the modulated composite beam is polarized;

wherein the selective reflector includes a polarization-sensitive reflector configured to reflect at least a portion of the modulated composite beam; and

further comprising a polarization rotator aligned to receive the modulated composite beam along the fifth axis and aligned to receive the modulated scanned beam and configured to cause the polarization of the modulated scanned beam to be rotated substantially 90 degrees relative to the received modulated composite beam;

whereby the selective reflector is configured to pass a substantial portion of the scanned composite beam toward the field of view.

6. The integrated photonics module of claim 2 wherein the fifth axis is substantially parallel to the fourth axis and wherein the selective reflector is configured to pass at least a portion of the received modulated composite beam toward the beam scanner and to reflect at least a portion of the modulated scanned beam toward the field of view.

7. The integrated photonics module of claim 6 further comprising a polarization rotator aligned to receive the modulated composite beam and the scanned beam and rotate the polarization of the scanned beam to an orientation substantially 90 degrees from the received modulated composite beam.

8. The integrated photonics module of claim 7 wherein the selective reflector comprises a polarization-selective reflector.

9. A scanned beam display engine comprising:

an optical frame configured for mechanical mounting to a host system;

at least one light source coupled to the housing and operable to emit a beam of modulated light; and

a MEMS scanner coupled to the housing aligned to receive the beam of modulated light and operable to periodically scan the beam of modulated light across a field-of view as a scanned beam to produce a projected video image.

10. The scanned beam display engine of claim 9 wherein the light source includes at least two light sources and further comprising:

a beam combiner mechanically coupled to the optical frame and held in alignment thereby and configured to combine beams of modulated light from the at least two light beams into a composite beam of modulated light; and

wherein the beam of modulated light the MEMS scanner is aligned to receive includes the composite beam of modulated light.

11. The scanned beam display engine of claim 9 further comprising:

a selective fold mirror aligned to receive the beam of modulated light and direct the beam of modulated light toward the MEMS scanner.

12. The scanned beam display engine of claim 11 wherein the selective fold mirror is configured to substantially direct one plane of polarization toward the MEMS scanner.

13. The scanned beam display engine of claim 12 further comprising:

a polarization rotator aligned to receive the beam of modulated light from the selective fold mirror and operable to convert the beam of plane-polarized modulated light to a circularly polarized beam directed toward the MEMS scanner.

14. The scanned beam display engine of claim 13 wherein the polarization rotator is further aligned to receive the circularly polarized scanned beam from the MEMS scanner and configured to convert the circular polarization of the scanned beam to a plane polarization oriented substantially at a right angle to the plane of polarization of the light received from the selective fold mirror.

15. The scanned beam display engine of claim 14 wherein the MEMS scanner is aligned to receive the circularly polarized beam from the polarization rotator from a direction substantially normal to a mirror surface of the MEMS scanner.

16. The scanned beam display engine of claim 12 further comprising at least one light detector aligned to receive scattered light from the selective fold mirror.

24. The beam scanner of claim 16 wherein the optical frame is further operative as a heat sink to remove heat from the at least two light sources.

25. The beam scanner of claim 16 wherein the at least two light sources include at least one diode laser and at least one SHG laser.

26. The beam scanner of claim 16 wherein the at least two light sources include at least three light sources, the at least three light sources comprising a red laser diode, a blue laser, and a green SHG laser.

27. The beam scanner of claim 16 further comprising a beam scanner controller operatively coupled to the at least two light sources and the MEMS scanner.

17. A beam scanner comprising:

a selective reflector aligned to receive a first beam of light along a first axis and reflect at least a portion of the first beam of light along a second axis; and

a MEMS beam scanner aligned to receive the first beam of light along the second axis from the selective reflector and operable to reflect the first beam of light as a periodically scanned second beam of light toward a field of view substantially subtended by the selective reflector;

wherein the selective reflector is configured to allow a substantial portion of the second beam of light to pass through to the field of view.

18. The beam scanner of claim 17 wherein:

the selective reflector includes a polarizing beam splitter;

the first beam of light is polarized in a direction the polarizing beam splitter is configured to reflect; and

the second beam of light is polarized in a direction the polarizing beam splitter is configured to pass.

19. The beam scanner of claim 18 further comprising:

a polarization rotator aligned between the polarizing beam splitter and the MEMS beam scanner.

20. The beam scanner of claim 19 wherein the polarization rotator includes a quarter-wave retarder.

21. The beam scanner of claim 17 further comprising an optical frame operative to maintain alignment between the selective reflector and the MEMS scanner.

23. The beam scanner of claim 21 further comprising:

at least two light sources operable to emit at least third and fourth beams of modulated light; and

a beam combiner configured to combine the at least third and fourth beams of modulated light into the first beam of light and launch the first beam of light along the first axis toward the selective reflector; and

wherein

the optical frame is operative to maintain alignment between the at least two light sources, the beam combiner, the selective reflector, and the MEMS scanner.

28. The beam scanner of claim 20 wherein at least a portion of the beam scanner controller is mechanically coupled to the optical frame.

29. The beam scanner controller of claim 28 wherein substantially the entire beam scanner controller is mechanically coupled to the optical frame.

30. The beam scanner of claim 28 wherein the optical frame is further configured to be physically mounted to a host system.

31. The beam scanner of claim 20 wherein the beam scanner controller includes a MEMS controller operable to drive the MEMS scanner.

32. The beam scanner of claim 31 wherein the beam scanner controller is further operable to generate and transmit a scanner synchronization signal.

33. The beam scanner of claim 31 wherein the beam scanner controller further includes at least one sensor operable to measure an operating variable and transmit a signal corresponding to the measured operating variable.

34. The beam scanner of claim 33 wherein the operating variable includes at least one selected from the list consisting of ambient light, temperature, automatic phase measurement, and scanner fault.

35. The beam scanner of claim 31 wherein the beam scanner controller further includes light source drivers operable to receive a light source drive signal and responsively drive the at least three lasers to emit modulated beams of light.

36. The beam scanner of claim 35 wherein the beam scanner controller further includes a video controller operable to receive a synchronization signal from the MEMS controller and receive a video image and responsively transmit the light source drive signal to the light source drivers synchronously with the synchronization signal.

37. The beam scanner of claim 36 wherein the video controller is operable to receive the video image from a system resource.

38. The beam scanner of claim 37 further comprising a media module operatively coupled to the system resource and the video controller and wherein the media module is operable to receive a video image in a first format from the system resource, convert the video image to a second format compatible with the video controller, and transmit the video image in the second format to the video controller.

39. The beam scanner of claim 23 wherein the optical frame is further configured to be physically mounted to a host system.

40. The beam scanner of claim 17 wherein the second axis is aligned with a point substantially centered in the field of view.

41. The beam scanner of claim 17 wherein the MEMS beam scanner has a rest position and the second axis is aligned substantially normal to the rest position of the MEMS beam scanner.

42. The beam scanner of claim 41 wherein the rest position of the MEMS beam scanner corresponds to a position taken by the mirror of the MEMS beam scanner when power is removed from the MEMS beam scanner.

52. The method for scanning a beam of light of claim 42 wherein the third parallel axes are substantially parallel to the first axis.

54. The method for scanning a beam of light of claim 42 further comprising the step of:

emitting the plurality of second modulated beams of light and launching the plurality of second modulated beams of light along the corresponding plurality of third parallel axes.

55. The method for scanning a beam of light of claim 54 further comprising:

responsive to receiving a video image, generating a plurality of light source drive signals corresponding to the second plurality of modulated beams of light; and

driving a corresponding plurality of light sources.

56. The method for scanning a beam of light of claim 55 wherein the plurality of light source drive signals are generated synchronously with the periodicity of the scanned reflection of the first modulated beam of light.

22. The beam scanner of claim B 14 further comprising at least one light source operable to emit a beam of modulated light coupled to the housing and held in alignment with the selective reflector and the MEMS scanner by the housing.

43. A method for scanning a beam of light to project an image comprising the steps of:

receiving a first modulated beam of light from a selective mirror; and

transmitting a periodically scanned reflection of the first modulated beam of light through the selective mirror to a field of view beyond the selective mirror.

44. The method for scanning a beam of light of claim 43 wherein the first modulated beam of light is transmitted from the selective mirror in a first polarization state and the reflection of the first modulated beam of light is transmitted through the selective mirror in a second polarization state.

45. The method for scanning a beam of light of claim 44 wherein the first polarization state consists essentially of P-polarization and the second polarization state consists essentially of S-polarization.

46. The method for scanning a beam of light of claim 44 further comprising the step of rotating the polarization of the first modulated beam of light from the first polarization state to the second polarization state.

47. The method for scanning a beam of light of claim 46 wherein the step of rotating the polarization of the first modulated beam of light from the first polarization state to the second polarization state further comprises:

converting the first modulated beam of light from a first plane polarization state to a circular polarization state; and

after reflecting the first modulated beam of light, converting the first modulated beam of light from the circular polarization state to a second plane polarization state different from the first plane polarization state.

48. The method for scanning a beam of light of claim 43 wherein the first modulated beam of light is received from the selective mirror along a first axis and the field of view is subtended by the selective mirror.

49. The method for scanning a beam of light of claim 48 further comprising the step of:

at the selective mirror, reflecting the first modulated beam of light along the first axis from a second axis.

50. The method for scanning a beam of light of claim 49 wherein the first modulated beam of light comprises a modulated composite beam of light.

51. The method for scanning a beam of light of claim 50 further comprising the steps of:

receiving a plurality of second modulated beams of light along a corresponding plurality of third parallel axes;

combining the received plurality of second beams of light into the first modulated beam of light; and

directing the first modulated beam of light along the second axis toward the selective mirror.

53. The method for scanning a beam of light of claim 43 wherein the second axis is substantially perpendicular to the third parallel axes and the first axis.

57. The method for scanning a beam of light of claim 51 wherein each of the plurality of second modulated beams of light comprises a wavelength of light;

and

the first modulated beam of light comprises a composite of the wavelengths of the plurality of second modulated beams of light.

58. A system comprising:

system resources operable to provide a video signal, power, and a user interface;

a mount system configured to receive an integrated photonics module; and

a housing having an aperture therein, the aperture being aligned to the position of an exit face of and integrated optical engine portion of an integrated photonics module.

59. The system of claim 58 wherein the system comprises a cellular telephone;

and

further comprising an integrated photonics module;

whereby the cellular telephone is operable to project a video image through the aperture.

60. The system of claim 58 wherein the system comprises a motor vehicle and the video signal includes gauge information;

and

further comprising;

a beam-splitting surface aligned with an occupant position; and

an integrated photonics module operable to project the gauge information toward the beam-splitting surface;

whereby the occupant may simultaneously view gauge information and an operating environment through the beam splitting surface.

61. The system of claim 58 wherein the system comprises a digital camera;

and

further comprising;

a user interface operable to capture an image; and

an integrated photonics module operable by the viewer for viewing the captured image.