SOLID STATE OPTICAL PHASED ARRAY LIDAR AND METHOD OF USING SAME

• US 20150293224A1
• Filed: 03/31/2014
• Published: 10/15/2015
• Est. Priority Date: 05/09/2013
• Status: Active Grant

• Current Assignee: Quanergy Systems, Inc.
• Original Assignee: Quanergy Systems, Inc.
• Inventors: ELDADA, Louay, YU, Tianyue, PACALA, Angus
• Granted Patent: US 10,132,928 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G01S 17/89 for mapping or imaging
• CPC Class Codes: G01S 7/4814 of transmitters alone

Abstract

A lidar-based apparatus and method are used for the solid state steering of laser beams using Photonic Integrated Circuits. Integrated optic design and fabrication micro- and nanotechnologies are used for the production of chip-scale optical splitters that distribute an optical signal from a laser essentially uniformly to an array of pixels, said pixels comprising tunable optical delay lines and optical antennas. Said antennas achieve out-of-plane coupling of light.

As the delay lines of said antenna-containing pixels in said array are tuned, each antenna emits light of a specific phase to form a desired far-field radiation pattern through interference of these emissions. Said array serves the function of solid state optical phased array.

By incorporating a large number of antennas, high-resolution far-field patterns can be achieved by an optical phased array, supporting the radiation pattern beam forming and steering needed in solid state lidar, as well as the generation of arbitrary radiation patterns as needed in three-dimensional holography, optical memory, mode matching for optical space-division multiplexing, free space communications, and biomedical sciences. Whereas imaging from an array is conventionally transmitted through the intensity of the pixels, the optical phased array allows imaging through the control of the optical phase of pixels that receive coherent light waves from a single source.

Claims

1. A time-of-flight lidar ranging apparatus comprising:

a) at least one chip comprising at least one optical splitter, a plurality of optical delay lines, and a plurality of out-of-plane optical couplers laid out in an array configuration

b) at least one optical receiver

c) processing electronics

d) control electronics

2. The apparatus of claim 1 wherein at least one of said at least one optical splitter is a symmetric splitter with one input and a plurality of outputs

3. The apparatus of claim 1 wherein at least one of said at least one optical splitter is an asymmetric splitter functioning as a power tap

4. The apparatus of claim 1 wherein said at least one optical splitter is based on a Y-branch

5. The apparatus of claim 1 wherein said at least one optical splitter is based on a directional coupler

6. The apparatus of claim 1 wherein said at least one optical splitter is based on a multimode interference coupler

7. The apparatus of claim 1 wherein said at least one optical splitter is tunable

8. The apparatus of claim 7 wherein said at least one tunable optical splitter is based on thermo-optic tuning

9. The apparatus of claim 7 wherein said at least one tunable optical splitter is based on electro-optic tuning

10. The apparatus of claim 7 wherein said at least one tunable optical splitter is based on electroabsorption tuning

11. The apparatus of claim 7 wherein said at least one tunable optical splitter is based on free carrier absorption tuning

12. The apparatus of claim 7 wherein said at least one tunable optical splitter is based on magneto-optic tuning

13. The apparatus of claim 7 wherein said at least one tunable optical splitter is based on liquid crystal tuning

14. The apparatus of claim 7 wherein said at least one tunable optical splitter is based on all-optical tuning

15. The apparatus of claim 1 wherein at least a subset of said plurality of optical delay lines are based on true time delays

16. The apparatus of claim 1 wherein at least a subset of said plurality of optical delay lines are based on gain elements

17. The apparatus of claim 1 wherein at least a subset of said plurality of optical delay lines are based on all-pass filters

18. The apparatus of claim 1 wherein at least a subset of said plurality of optical delay lines are based on Bragg gratings

19. The apparatus of claim 1 wherein at least a subset of said plurality of optical delay lines are based on dispersive materials

20. The apparatus of claim 1 wherein at least a subset of said plurality of optical delay lines are based on wavelength tuning

21. The apparatus of claim 1 wherein at least a subset of said plurality of optical delay lines are based on phase tuning

22. The apparatus of claim 21 wherein said phase-tuning-based optical delay lines are actuated based on thermo-optic tuning

23. The apparatus of claim 21 wherein said phase-tuning-based optical delay lines are actuated based on electro-optic tuning

24. The apparatus of claim 21 wherein said phase-tuning-based optical delay lines are actuated based on electroabsorption tuning

25. The apparatus of claim 21 wherein said phase-tuning-based optical delay lines are actuated based on free carrier absorption tuning

26. The apparatus of claim 21 wherein said phase-tuning-based optical delay lines are actuated based on magneto-optic tuning

27. The apparatus of claim 21 wherein said phase-tuning-based optical delay lines are actuated based on liquid crystal tuning

28. The apparatus of claim 21 wherein said phase-tuning-based optical delay lines are actuated based on all-optical tuning

29. The apparatus of claim 1 wherein at least a subset of said plurality of out-of-plane optical couplers are based on gratings

30. The apparatus of claim 1 wherein at least a subset of said plurality of out-of-plane optical couplers are based on holographic optical elements

31. The apparatus of claim 1 wherein at least a subset of said plurality of out-of-plane optical couplers are based on mirrors

32. The apparatus of claim 1 wherein at least a subset of said plurality of out-of-plane optical couplers are based on total internal reflection interfaces

33. The apparatus of claim 1 wherein at least a subset of said plurality of out-of-plane optical couplers are based on lenses

34. The apparatus of claim 1 wherein said chip is compatible with a complementary metal-oxide-semiconductor process

35. The apparatus of claim 34 wherein said chip is preferably based on a silicon on insulator structure

36. The apparatus of claim 34 wherein said chip and said at least one optical receiver are integrated

37. The apparatus of claim 34 wherein said chip and said processing electronics are integrated

38. The apparatus of claim 34 wherein said chip and said control electronics are integrated

39. The apparatus of claim 34 wherein said chip, said at least one optical receiver, said processing electronics and said control electronics are integrated

40. The apparatus of claim 1 wherein said chip is held at essentially constant temperature

41. The apparatus of claim 38 wherein said essentially constant temperature is obtained using a method that utilizes at least one resistive heater

42. The apparatus of claim 38 wherein said essentially constant temperature is obtained using a method that utilizes at least one thermoelectric cooler

43. The apparatus of claim 38 wherein said essentially constant temperature is obtained using a method that utilizes at least one resistance temperature detector

44. The apparatus of claim 38 wherein said essentially constant temperature is obtained using a method that utilizes at least one thermistor

45. The apparatus of claim 1 wherein said lidar ranging apparatus chip creates in the far field a radiation pattern that is essentially a spot

46. The apparatus of claim 43 wherein said spot is scanned to produce two-dimensional scans

47. The apparatus of claim 43 wherein the lidar ranging apparatus comprises a receiver used to collect time of flight data that correspond to depth measurements

48. The apparatus of claim 43 wherein the lidar ranging apparatus comprises a one-dimensional array of receivers used to collect time of flight data that correspond to depth measurements

49. The apparatus of claim 43 wherein the lidar ranging apparatus comprises a two-dimensional array of receivers used to collect time of flight data that correspond to depth measurements

50. The apparatus of claim 44 wherein the two-dimensional scans are combined with time of flight depth measurements to produce three-dimensional maps

51. The apparatus of claim 1 wherein said lidar ranging apparatus chip creates in the far field a radiation pattern whose envelope is elongated

52. The apparatus of claim 49 wherein said radiation pattern is scanned essentially perpendicularly to its long dimension to produce two-dimensional scans

53. The apparatus of claim 49 wherein the lidar ranging apparatus comprises a one-dimensional array of receivers used to collect time of flight data that correspond to depth measurements

54. The apparatus of claim 49 wherein the lidar ranging apparatus comprises a two-dimensional array of receivers used to collect time of flight data that correspond to depth measurements

55. The apparatus of claim 50 wherein the two-dimensional scans are combined with time of flight depth measurements to produce three-dimensional maps

56. The apparatus of claim 1 wherein said lidar ranging apparatus chip creates in the far field a radiation pattern whose envelope essentially covers the scene being mapped

57. The apparatus of claim 54 wherein the lidar ranging apparatus comprises a two-dimensional array of receivers used to collect time of flight data that correspond to depth measurements

58. The apparatus of claim 54 wherein the two-dimensional array measurements are combined with time of flight depth measurements to produce three-dimensional maps

60. The method of claim 57 wherein said at least one optical splitter is tunable

61. The method of claim 57 wherein at least a subset of said plurality of optical delay lines are based on true time delays

62. The method of claim 57 wherein at least a subset of said plurality of optical delay lines are based on gain elements

63. The method of claim 57 wherein at least a subset of said plurality of optical delay lines are based on all-pass filters

64. The method of claim 57 wherein at least a subset of said plurality of optical delay lines are based on Bragg gratings

65. The method of claim 57 wherein at least a subset of said plurality of optical delay lines are based on dispersive materials

66. The method of claim 57 wherein at least a subset of said plurality of optical delay lines are based on wavelength tuning

67. The method of claim 57 wherein at least a subset of said plurality of optical delay lines are based on phase tuning

68. The method of claim 57 wherein at least a subset of said plurality of out-of-plane optical couplers are based on gratings

69. The method of claim 57 wherein at least a subset of said plurality of out-of-plane optical couplers are based on holographic optical elements

70. The method of claim 57 wherein at least a subset of said plurality of out-of-plane optical couplers are based on mirrors

71. The method of claim 57 wherein at least a subset of said plurality of out-of-plane optical couplers are based on total internal reflection interfaces

72. The method of claim 57 wherein at least a subset of said plurality of out-of-plane optical couplers are based on lenses

73. The method of claim 57 wherein said chip is compatible with a complementary metal-oxide-semiconductor process

74. The method of claim 71 wherein said chip is preferably based on a silicon on insulator structure

75. The method of claim 71 wherein said chip includes control electronics

76. The method of claim 71 wherein said chip includes processing electronics

77. The method of claim 57 wherein said chip is held at essentially constant temperature

78. The method of claim 75 wherein said essentially constant temperature is obtained using a method that utilizes at least one resistive heater

79. The method of claim 75 wherein said essentially constant temperature is obtained using a method that utilizes at least one thermoelectric cooler

80. The method of claim 75 wherein said essentially constant temperature is obtained using a method that utilizes at least one resistance temperature detector

81. The method of claim 75 wherein said essentially constant temperature is obtained using a method that utilizes at least one thermistor

82. The method of claim 57 wherein said lidar ranging apparatus chip creates in the far field a radiation pattern that is essentially a spot

83. The method of claim 80 wherein said spot is scanned to produce two-dimensional scans

84. The method of claim 80 wherein the lidar ranging apparatus comprises on the receiving end a receiver used to collect time of flight data that correspond to depth measurements

85. The method of claim 80 wherein the lidar ranging apparatus comprises on the receiving end a one-dimensional array of receivers used to collect time of flight data that correspond to depth measurements

86. The method of claim 80 wherein the lidar ranging apparatus comprises on the receiving end a two-dimensional array of receivers used to collect time of flight data that correspond to depth measurements

87. The method of claim 81 wherein the two-dimensional scans are combined with time of flight depth measurements to produce three-dimensional maps

88. The method of claim 57 wherein said lidar ranging apparatus chip creates in the far field a radiation pattern whose envelope is elongated

89. The method of claim 86 wherein said radiation pattern is scanned essentially perpendicularly to its long dimension to produce two-dimensional scans

90. The method of claim 86 wherein the lidar ranging apparatus comprises on the receiving end a one-dimensional array of receivers used to collect time of flight data that correspond to depth measurements

91. The method of claim 86 wherein the lidar ranging apparatus comprises on the receiving end a two-dimensional array of receivers used to collect time of flight data that correspond to depth measurements

92. The method of claim 87 wherein the two-dimensional scans are combined with time of flight depth measurements to produce three-dimensional maps

93. The method of claim 57 wherein said lidar ranging apparatus chip creates in the far field radiation pattern that is essentially a two-dimensional array of spots

94. The method of claim 91 wherein the lidar ranging apparatus comprises on the receiving end a two-dimensional array of receivers used to collect time of flight data that correspond to depth measurements

95. The method of claim 91 wherein the two-dimensional array measurements are combined with time of flight depth measurements to produce three-dimensional maps

59. A method for time-of-flight lidar ranging utilizing an apparatus comprising a chip with at least one optical splitter, a plurality of optical delay lines, and a plurality of out-of-plane optical couplers laid out in a two-dimensional array configuration