Scanned-beam heads-up display and related systems and methods

• US 20070103747A1
• Filed: 08/04/2006
• Published: 05/10/2007
• Est. Priority Date: 02/04/2004
• Status: Active Grant

• Current Assignee: Microvision, Inc.
• Original Assignee: Microvision, Inc.
• Inventors: Urey, Hakan, Powell, Karlton, Malik, Amjad, Hannigan, Russell
• Granted Patent: US 7,460,305 B2
• Time in Patent Office: Days
• US Class Current: 359/13
• CPC Class Codes: G02B 13/22 Telecentric objectives or lens systems
• CPC Class Codes: G02B 2027/0118 comprising devices for improving the contrast of the display / brillance control visibility
• CPC Class Codes: G02B 2027/0123 comprising devices increasing the field of view
• CPC Class Codes: G02B 26/10 Scanning systems
• CPC Class Codes: G02B 27/01 Head-up displays
• CPC Class Codes: G02B 27/0101 characterised by optical features G02B27/0172 takes precedence
• CPC Class Codes: G02B 3/0087 with index gradient
• CPC Class Codes: G09G 3/001 using specific devices not provided for in groups G09G3/02 - G09G3/36, e.g. using an intermediate record carrier such as a film slide; Projection systems; Display of non-alphanumerical information, solely or in combination with alphanumerical information, e.g. digital display on projected diapositive as background slide projectors per se G03B23/00 = 42 HP
• 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
• CPC Class Codes: Y10S 359/90 Methods

Abstract

A heads-up display that includes a scanner and a projection assembly. The scanner generates an image by sweeping a beam of electromagnetic energy, and the projection assembly directs the image into a predetermined viewing space having a region with a substantially uniform intensity profile. Such a heads-up display can often be made smaller than a conventional heads-up display, and can often generate an image having a higher quality than an image generated by a conventional display. Furthermore, one can often calibrate and recalibrate such a display without physically modifying or replacing a component of the display or of a vehicle incorporating the display.

Claims

1. A heads-up display, comprising:

a scanner assembly operable to generate an image by sweeping a beam of electromagnetic energy in at least one dimension; and

a projection assembly operable to direct the image into a predetermined viewing space having a substantially uniform intensity profile in a cross section having a region that is substantially normal to a viewing dimension.

2. The heads-up display of claim 1 wherein a brightest region of the profile in the cross section across a first measurement aperture of not greater than approximately 8 millimeters differs from a dimmest region of the profile in the cross section across a second measurement aperture of not greater than approximately 8 millimeters by no more than approximately ±

11%.

3. The heads-up display of claim 2 wherein the first and second measurement apertures are each no greater than approximately 1 millimeters.

4. The heads-up display of claim 1 wherein:

the projection assembly comprises an exit-pupil expander; and

the scanner is operable to generate the image by sweeping the beam in two dimensions onto the exit-pupil expander.

5. The heads-up display of claim 1 wherein a planar projection of the cross section of the viewing space has a hexagonal shape.

6. The heads-up display of claim 1 wherein a planar projection of the cross section of the viewing space has an elongated hexagonal shape.

7. The heads-up display of claim 1 wherein the cross section of the viewing space is a planar cross section.

8. The heads-up display of claim 1 wherein a planar projection of the cross section of the viewing space has one dimension of at least 100 millimeters.

9. The heads-up display of claim 1 wherein:

the projection assembly is further operable to generate beamlets within the viewing space; and

a difference in the intensity profile over a measurement aperture of at least a portion of the viewing space is no greater than approximately ±

2%, the measurement aperture being no greater than approximately 8 millimeters.

10. The heads-up display of claim 9 wherein the measurement aperture is no greater than approximately 1 millimeters.

11. A method, comprising:

sweeping a beam of light in at least one dimension to generate an image; and

directing the image into a predetermined viewing space having a substantially uniform intensity envelope in a cross section having a region that is substantially normal to a viewing dimension.

12. The method of claim 11 wherein directing the image comprises generating a plurality of beamlets within the viewing space.

13. The method of claim 11 wherein:

a planar projection of the cross section has a predetermined shape; and

directing the image comprises generating within the viewing space a plurality of beamlets each having a planar cross section with substantially the predetermined shape.

14. A scanned-beam display, comprising:

a beam generator operable to generate an output beam of electromagnetic energy having a substantially uniform intensity profile in a planar cross section that is normal to a direction in which the output beam propagates; and

a beam scanner operable to generate an image by sweeping the output beam in at least one dimension.

15. The scanned-beam display of claim 14 wherein the beam generator comprises:

a beam source operable to generate an input beam having a non-uniform intensity profile in a planar cross section that is normal to a direction in which the input beam propagates; and

a beam conditioner operable to convert the input beam into the output beam.

16. The scanned-beam display of claim 14 wherein the beam generator comprises:

a beam source operable to generate an input beam having a non-uniform intensity profile in a planar cross section that is normal to a direction in which the input beam propagates; and

a top-hat converter operable to convert the input beam into the output beam.

17. The scanned-beam display of claim 14 wherein the beam generator comprises:

a beam source operable to generate an input beam having a non-uniform intensity profile in a planar cross section that is normal to a direction in which the input beam propagates; and

a clipping aperture operable to block an outer portion of the input beam and to generate the output beam from a passed inner portion of the input beam.

18. The scanned-beam display of claim 14 wherein the beam generator comprises:

a beam source operable to generate an input beam having a substantially Gaussian intensity profile in a planar cross section that is normal to a direction in which the input beam propagates; and

a beam conditioner operable to convert the input beam into the output beam by converting the substantially Gaussian intensity profile into the substantially uniform intensity profile.

19. The scanned-beam display of claim 14 wherein a brightest region of the output beam in the cross section differs from a dimmest region of the output beam in the cross section by no more than ±

10%.

20. The scanned-beam display of claim 14 wherein the output beam comprises visible light.

21. A method, comprising:

generating an output beam of electromagnetic energy having a substantially uniform intensity profile in a planar cross section that is normal to a direction in which the output beam propagates; and

sweeping the output beam in at least one dimension to generate an image.

22. The method of claim 21 wherein generating the output beam comprises:

generating an input beam having a non-uniform intensity profile in a planar cross section that is normal to a direction in which the input beam propagates; and

passing the input beam through a top-hat converter to generate the output beam.

23. The method of claim 21 wherein generating the output beam comprises:

generating an input beam having a substantially Gaussian intensity profile in a planar cross section that is normal to a direction in which the input beam propagates; and

clipping an outer portion of the input beam; and

generating the output beam from an unclipped inner portion of the input beam.

24. A heads-up display, comprising:

a beam generator operable to generate a beam of electromagnetic energy; and

a micro-electro-mechanical scanner operable to generate an image by sweeping the beam in at least one dimension.

25. The heads-up display of claim 24 wherein the scanner is operable to generate an image by resonantly sweeping the beam in a first dimension and by linearly sweeping the beam a second dimension that is substantially perpendicular to the first dimension.

26. A heads-up display, comprising:

a beam generator operable to generate a beam of electromagnetic energy; and

a scanner operable to generate an image by resonantly sweeping the beam in at least one dimension.

27. A method, comprising:

generating a beam of electromagnetic energy; and

resonantly sweeping the beam in one dimension to generate a virtual image that is reflected from a wind screen of a vehicle.

28. The method of claim 27 wherein resonantly sweeping the beam comprises generating the image while resonantly sweeping the beam in both directions of the dimension.

29. A heads-up display, comprising:

a scanner operable to generate an image by sweeping a beam of electromagnetic energy in at least one dimension; and

a projection assembly that includes a first microlens array operable to direct the image into a predetermined viewing space.

30. The heads-up display of claim 29 wherein the first microlens array comprises a varying-phase microlens array.

31. The heads-up display of claim 29 wherein the first microlens array comprises lenslets, one of the lenslets having a first value for a lenslet property and another of the lenslets having a second value for the lenslet property.

32. The heads-up display of claim 29 wherein the projection assembly comprises a second microlens array disposed adjacent to the first microlens array such that the first and second microlens arrays are together operable to direct the image into the predetermined viewing space.

33. The heads-up display of claim 29 wherein:

the first microlens array has a focal plane and a focal length from the focal plane; and

the projection assembly further includes a second microlens array having a focal plane and the focal length from the focal plane, the focal plane of the second microlens array being substantially parallel to and spaced the focal length from the focal plane of the first microlens array.

34. The heads-up display of claim 29 wherein the first microlens array comprises lenslets arranged in a pattern and is operable to cause a planar projection of the cross section of the viewing space to have the pattern.

35. The heads-up display of claim 29 wherein the first microlens array comprises lenslets arranged in an elongated hexagonal pattern and is operable to cause a planar projection of the cross section of the viewing space to have the elongated hexagonal pattern.

36. A method, comprising:

sweeping a beam having a profile in a cross section;

converting the profile of the beam into substantially a spatial sinc function;

performing a spatial Fourier Transform on the spatial sinc function to generate an image; and

directing the image into a predetermined viewing space with a wind screen of a vehicle.

37. The method of claim 36 wherein converting the profile of the beam comprises converting the profile of the beam into substantially a spatial sinc function using a dual-microlens array.

38. A scanned-beam display, comprising:

a beam generator operable to generate an output beam of electromagnetic energy having a substantially hexagonal planar cross section that is normal to a direction in which the output beam propagates; and

a beam scanner operable to generate an image by sweeping the output beam in at least one dimension.

39. The scanned-beam display of claim 38 wherein the beam generator comprises:

a beam source operable to generate an input beam having a non-hexagonal planar cross section that is normal to a direction in which the input beam propagates; and

a clipping aperture operable to convert the input beam into the output beam.

40. The scanned-beam display of claim 38 wherein the beam generator comprises:

a beam source operable to generate an input beam having a substantially circular planar cross section that is normal to a direction in which the input beam propagates; and

a clipping aperture operable to convert the input beam into the output beam by converting the substantially circular cross section into the substantially hexagonal cross section.

41. The scanned-beam display of claim 38 wherein the cross section of the output beam has a substantially elongated hexagonal shape.

42. A method, comprising:

generating an output beam of electromagnetic energy having a substantially hexagonally shaped planar cross section that is normal to a direction in which the output beam propagates; and

sweeping the output beam in at least one dimension to generate an image.

43. The method of claim 42, further comprising:

forming beamlets of the image, each beamlet having a substantially hexagonally shaped planar cross section that is normal to a direction in which the beamlet propagates; and

directing the beamlets into a predetermined viewing space.

44. A heads-up display, comprising:

a scanner operable to generate an image by sweeping a beam of electromagnetic energy in at least one dimension; and

a projection assembly having a mirror operable to reflect the image off of a wind screen and into a predetermined viewing space having a cross section, the mirror operable to maintain a dimension of the cross section at a substantially constant size for reflection of the image off of a predetermined region of the windshield.

45. The heads-up display of claim 44 wherein the mirror is operable to move the viewing space in a dimension substantially parallel to the cross section.

46. The heads-up display of claim 44 wherein the mirror is operable to move the viewing space in a dimension substantially normal to the cross section.

47. A heads-up display, comprising:

a scanner operable to generate an image by sweeping a beam of electromagnetic energy in at least one dimension; and

a projection assembly having a mirror operable to reflect the image off of a wind screen and into a predetermined viewing space having a cross section, the mirror operable to move the viewing space in a dimension substantially normal to the cross section.

48. A method, comprising:

sweeping a beam of electromagnetic energy in at least one dimension to generate an image; and

reflecting the image off of a wind screen and into a predetermined viewing space having a cross section such that a dimension of the cross section is maintained at a substantially constant size for reflection of the image off of a predetermined region of the wind screen.

49. A heads-up display, comprising:

a scanner operable to generate an image by sweeping a beam of electromagnetic energy in at least one dimension; and

a projection assembly operable to direct the image into a predetermined viewing space such that in a cross section of the viewing space having a region that is substantially normal to a viewing dimension, the image has a substantially uniform intensity profile.

50. The heads-up display of claim 49, further comprising a beam generator operable to generate the beam of electromagnetic energy having a substantially uniform intensity profile in a planar cross section that is normal to a direction in which the beam propagates.

51. The heads-up display of claim 49, further comprising:

a beam generator operable to generate the beam of electromagnetic energy having a hexagonal aperture and a substantially uniform intensity profile in a planar cross section that is normal to a direction in which the beam propagates; and

wherein the cross section of the viewing space has a hexagonal shape.

52. The heads-up display of claim 49, further comprising:

a beam generator operable to generate the beam of electromagnetic energy having a hexagonal aperture and a substantially uniform intensity profile in a planar cross section that is normal to a direction in which the beam propagates;

wherein the cross section of the viewing space has a hexagonal shape; and

wherein the viewing space includes beamlets each having a hexagonal aperture and a substantially uniform intensity profile in a planar cross section that is substantially parallel to the planar cross section of the viewing space.

53. A method, comprising:

generating an image by sweeping a beam of electromagnetic energy in at least one dimension; and

directing the image into a predetermined viewing space such that in a cross section of the viewing space having a region that is substantially normal to a viewing dimension, the image has a substantially uniform intensity profile.

54. The method of claim 53, further comprising generating the beam of electromagnetic energy having a substantially uniform intensity profile in a planar cross section that is normal to a direction in which the beam propagates.

55. The method of claim 53, further comprising:

generating the beam of electromagnetic energy having a hexagonal aperture and a substantially uniform intensity profile in a planar cross section that is normal to a direction in which the beam propagates; and

wherein the cross section of the viewing space has a hexagonal shape.

56. The method of claim 53, further comprising:

generating the beam of electromagnetic energy having a hexagonal aperture and a substantially uniform intensity profile in a planar cross section that is normal to a direction in which the beam propagates;

wherein the cross section of the viewing space has a hexagonal shape; and

wherein the viewing space includes beamlets each having a hexagonal aperture and a substantially uniform intensity profile in a planar cross section that is substantially parallel to the planar cross section of the viewing space.