2D scanning high precision LiDAR using combination of rotating concave mirror and beam steering devices

Patent metadata

Field	Value
Publication number	US-11977183-B2
Application number	US-202318102654-A
Country	US
Kind code	B2
Filing date	Jan 27, 2023
Priority date	Dec 31, 2016
Publication date	May 7, 2024
Grant date	May 7, 2024

Abstract

The present disclosure describes a system and method for coaxial LiDAR scanning. The system includes a first light source configured to provide first light pulses. The system also includes one or more beam steering apparatuses optically coupled to the first light source. Each beam steering apparatus comprises a rotatable concave reflector and a light beam steering device disposed at least partially within the rotatable concave reflector. The combination of the light beam steering device and the rotatable concave reflector, when moving with respect to each other, steers the one or more first light pulses both vertically and horizontally to illuminate an object within a field-of-view; obtain one or more first returning light pulses, the one or more first returning light pulses being generated based on the steered first light pulses illuminating an object within the field-of-view, and redirects the one or more first returning light pulses.

First claim

What is claimed is:

1. A light detection and ranging (LiDAR) scanning system, comprising:
one or more light sources configured to provide light pulses;
one or more beam steering apparatus optically coupled to the one or more light sources to receive the light pulses; the beam steering apparatus comprising a light beam steering device and a reflector,
wherein a combination of the light beam steering device and the reflector, when moving with respect to each other, is configured to:
scan the light pulses in both vertical and horizontal directions to illuminate one or more objects within a field-of-view, and
receive return light pulses formed based on the illumination of the one or more objects within the field-of-view;

a detector, and
a microcontroller, wherein the one or more beam steering apparatus, the detector, and the microcontroller are configured to:
form a plurality of sub-frames based on the return light pulses, and
interlace the plurality of sub-frames to form a single frame,
wherein the single frame has a higher resolution than any of the plurality of sub-frames.

2. The LiDAR system of claim 1 , wherein the reflector is an oscillation mirror or a polygonal-shaped structure.

3. The LiDAR system of claim 1 , wherein in forming the plurality of sub-frames, the one or more beam steering apparatus, the detector, and the microcontroller are configured to:
form a first sub-frame of the plurality of sub-frames based on scanning at least some of the light pulses across the field-of-view in both the vertical and horizontal directions; and
form a second sub-frame of the plurality of sub-frames based on scanning at least some of the light pulses across the field-of-view in both the vertical and horizontal directions at a scanning offset with respect to the scanning to form the first sub-frame.

4. The LiDAR system of claim 3 , wherein in forming the first sub-frame, the one or more beam steering apparatus is further configured to direct at least some of the light pulses across a reflective surface of the light beam steering device; and
wherein in forming the second sub-frame, the beam steering apparatus is further configured to direct, at the scanning offset, at least some of the light pulses across a reflective surface of the light beam steering device.

5. The LiDAR system of claim 3 , wherein the one or more of the beam steering apparatus, the detector, and the microcontroller are further configured to:
form a third sub-frame of the plurality of sub-frames based on scanning at least some of the light pulses across the field-of-view in both the vertical and horizontal directions at a second scanning offset with respect to the scanning to form the second sub-frame.

6. The LiDAR system of claim 1 , wherein the plurality of sub-frames interlaced to form the single frame are successive or consecutive.

7. The LiDAR system of claim 1 , wherein, among a group consisting of the plurality of sub-frames interlaced to form the single frame, one or both of vertical and horizontal scanning directions of a sub-frame is offset relative to a respective vertical or horizontal scanning direction of other sub-frames within the group.

8. The LiDAR system of claim 1 , wherein the single frame has a frame pattern representing overlapping in a scanning range covered by the beam steering apparatus.

9. The LiDAR system of claim 1 , wherein at least one of the light beam steering device and the reflector are configured to have rotational velocity perturbations such that scanning angle distribution across the horizontal and vertical directions are randomized.

10. The LiDAR system of claim 1 , wherein the microcontroller is further configured to:
calculate distances of the one or more objects based on the return light pulses; and
form a three-dimensional point cloud using the calculated distances and the sub-frames.

11. The LiDAR system of claim 10 , wherein the microcontroller is further configured to:
determine a sampling rate based on the sub-frames;
determine a relative velocity of the one or more objects with respect to the LiDAR system; and
compensate for the sampling rate and the relative velocity in forming the three-dimensional point cloud.

12. The LiDAR system of claim 1 , wherein the light beam steering device comprises a polyhedron having plurality of reflective facets.

13. The LiDAR system of claim 12 , wherein the polyhedron comprises one or more facets that are asymmetrical to facilitate at least one of offsetting one or both of vertical and horizontal scanning directions between the plurality of sub-frames or changing an interlacing raster pattern of the single frame.

14. The LiDAR system of claim 1 , wherein the detector is configured to:
detect the return light pulses to generate detected data; and wherein the microcontroller is configured to:
aggregate the field-of-view according to the detected data to form the plurality of sub-frames.

15. The LiDAR system of claim 1 , wherein the light pulses are included in a plurality of light beams, and wherein the combination of the light beam steering device and the reflector are configured to scan the plurality of light beams to obtain the return light pulses.

16. A light detection and ranging (LiDAR) system, comprising:
a light source configured to emit pulses of light;
a scanner configured to scan at least a portion of the emitted pulses of light along an interlaced scan pattern, wherein the scanner comprises:
a first scanning mirror configured to scan the portion of the emitted pulses of light, and
a second scanning mirror configured to scan the portion of the emitted pulses of light,
wherein the first scanning mirror and the second scanning mirror are configured to scan the portion of the emitted pulses of light in both vertical and horizontal directions to illuminate one or more objects within a field-of-view,
and wherein the interlaced scan pattern comprises a plurality of sub-patterns,

a detector configured to detect at least a portion of the scanned pulses of light scattered by the one or more objects, the scattered pulses of light being received by the scanner, and
a microcontroller, wherein the scanner, the detector and the microcontroller are configured to:
form a plurality of sub-frames based on the scattered pulses of light, and
interlace the plurality of sub-frames to form a single frame,
wherein the single frame has a higher resolution than any of the plurality of sub-frames.

17. The LiDAR system of claim 16 , wherein in forming the plurality of sub-frames, the scanner, the detector, and the microcontroller are configured to:
form a first sub-frame of the plurality of sub-frames based on scanning at least some of the emitted pulses of light across the field-of-view in both the vertical and horizontal directions; and
form a second sub-frame of the plurality of sub-frames based on scanning at least some of the emitted pulses of light across the field-of-view in both the vertical and horizontal directions at a scanning offset with respect to the scanning to form the first sub-frame.

18. The LiDAR system of claim 17 , wherein in forming the first sub-frame, the scanner is further configured to direct at least some of the light pulses across a reflective surface of a mirror of the scanner; and
wherein in forming the second sub-frame, the scanner is further configured to direct, at the scanning offset, at least some of the emitted pulses of light across a reflective surface of the mirror of the scanner.

19. The LiDAR system of claim 17 , wher

Assignees

• Innovusion Inc
• Seyond Inc

Inventors

• Bao Junwei
• Li Yimin
• Zhang Rui

Classifications

• G01S7/4812 Primary

  transmitted and received beams following a coaxial path · CPC title

• G01S7/4816

  of receivers alone · CPC title

• G01S7/4817

  relating to scanning · CPC title

• G01S17/10 Primary

  using transmission of interrupted, pulse-modulated waves (determination of distance by phase measurements G01S17/32) · CPC title

• G01S17/42

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