Monostatic lidar transceiver system

Patent metadata

Field	Value
Publication number	US-2024230851-A1
Application number	US-202418618256-A
Country	US
Kind code	A1
Filing date	Mar 27, 2024
Priority date	May 1, 2020
Publication date	Jul 11, 2024
Grant date	—

Abstract

A LiDAR system includes a light source and an arrayed micro-optic configured to receive light from the light source so as to produce and project a two-dimensional array of light spots on a scene. The LiDAR system also includes receiver optics having an array of optical detection sites configured so as to be suitable for establishing a one-to-one correspondence between light spots in the two-dimensional array and optical detection sites in the receiver optics. The LiDAR system further includes a birefringent prism and a lens. The LiDAR system may also include a mask placed in the light path between the birefringent prism and the receiver optics. Alternatively, the LiDAR system may include a controller programmed to activate or deactivate each optical detection site.

First claim

1 - 26 . (canceled)

27 . A system for operation of a light detection and ranging (LiDAR) system, comprising:
an arrayed micro-optic having an array of optical emission sites configured to receive light from a light source so as to produce and project a two-dimensional array of light spots on a scene; receiver optics having an array of optical detection sites configured so as to be suitable for establishing a one-to-one correspondence between the light spots in the two-dimensional array and the optical detection sites in the receiver optics; and a controller configured to selectively activate or deactivate or each optical emission site of the array of optical emission sites and/or each optical detection site of the array of optical detection sites.

28 . The system of claim 27 , wherein a size of each optical detection site is smaller than a size of each light spot projected onto the receiver optics, and the controller is further configured to selectively activate or deactivate each optical detection site to correspond to a calculated or measured aberrated shape of a light spot received in a focal plane of the array of optical detection sites.

29 . The system of claim 27 , wherein an activation state of at least one emission site of the array of optical emission sites determines an activation state of an associated at least one optical detection site of the array of optical detection sites.

30 . The system of claim 27 , wherein the controller is further configured to:
produce and project the two-dimensional array of light spots on the scene, by the arrayed micro-optic, such that the light travels a light path from the arrayed micro-optic to a lens, from the lens to a birefringent prism, from the birefringent prism to a quarter wave plate, and from the quarter wave plate to the scene, wherein the light as reflected from the scene travels from the scene to the quarter wave plate, from the quarter wave plate to the birefringent prism, from the birefringent prism to the lens, and from the lens to the receiver optics; and receive, by the receiver optics, the light as reflected from the scene, each of the light spots in the two-dimensional array having the one-to-one correspondence with the optical detection sites in the receiver optics, a mask having an array of apertures being located in the light path between the lens and the receiver optics, each of the apertures being located in front of a respective one of the optical detection sites.

31 . The system of claim 30 , wherein the birefringent prism comprises a birefringent wedge.

32 . The system of claim 30 , wherein the arrayed micro-optic comprises a micro-opto-electro-mechanical system (MOEMS) chip having a waveguide.

33 . The system of claim 32 , wherein the mask is coupled to the MOEMS chip.

34 . The system of claim 32 , wherein a distance between the MOEMS chip and the receiver optics is in the range of 5 to 30 micrometers.

35 . The system of claim 32 , wherein the waveguide comprises a transparent substrate.

36 . The system of claim 32 , wherein the MOEMS chip and the receiver optics form a monolithic structure.

37 . The system of claim 36 , wherein the receiver optics include a detector chip and wherein the MOEMS chip is bonded to the detector chip.

38 . The system of claim 32 , wherein the MOEMS chip comprises a plurality of optical gratings.

39 . The system of claim 38 , wherein the plurality of optical gratings and the receiver optics are arranged in the same plane.

40 . The system of claim 38 , wherein each of the plurality of optical gratings corresponds to one optical emission site of the array of optical emission sites.

41 . The system of claim 38 , wherein a plurality of grating couplers couple incident light from each grating of the plurality of optical gratings into the waveguide.

42 . The system of claim 41 , wherein the plurality of grating couplers are made from silicon nitride, wherein the optical gratings are made from silicon or silicon nitride, and wherein the waveguide is made from silicon or silicon nitride.

43 . The system of claim 30 , wherein the mask comprises a layer having a plurality of openings, each opening being in the light path leading to a respective one of the optical detection sites.

44 . The system of claim 43 , wherein the layer is made from a material selected from the group consisting of aluminum, copper, gold, platinum, chromium, titanium, silicon, carbon, graphite, or combinations thereof.

45 . The system of claim 30 , wherein a shape of at least one of the apertures corresponds to a calculated or measured aberrated shape of a light spot received in a focal plane of the respective optical detection site.

46 . The system of claim 30 , wherein a shape of at least one of the apertures is different from a shape of another one of the apertures.

47 . The system of claim 30 , wherein a shape of at least one of the apertures is selected to mitigate variations in manufacturing of the respective optical detection site or a thermal shift of the respective optical detection site.

48 . The system of claim 30 , wherein the optical detection sites are single-photon avalanche diode (SPAD) detectors.

49 . The system of claim 30 , wherein the optical detection sites are silicon photomultiplier (SiPM) detectors.

50 . The system of claim 30 , wherein the birefringent prism shifts a beam of light traveling through the birefringent prism by half a degree or less.

Assignees

• Charles Stark Draper Laboratory Inc

Inventors

• Moebius Michael G
• Benney Lucas D
• Spector Steven J
• Byrnes Steven J

Classifications

• G01S7/499 Primary

  using polarisation effects · CPC title

• G01S7/4813

  Housing arrangements · CPC title

• G01S17/02

  Systems using the reflection of electromagnetic waves other than radio waves (G01S17/66 takes precedence) · CPC title

• G01S17/42

  Simultaneous measurement of distance and other co-ordinates (indirect measurement G01S17/46) · CPC title

• G01S7/4817

  relating to scanning · CPC title