Adaptive LIDAR scanning methods

Patent metadata

Field	Value
Publication number	US-11796643-B2
Application number	US-201916426852-A
Country	US
Kind code	B2
Filing date	May 30, 2019
Priority date	May 30, 2019
Publication date	Oct 24, 2023
Grant date	Oct 24, 2023

Abstract

A light detection and ranging system includes synchronously scanning transmit and receive mirrors that scan a pulsed fanned laser beam in two dimensions. Imaging optics image a receive aperture onto an arrayed receiver that includes a plurality of light sensitive devices. Adaptive methods dynamically modify the size and location of the field of view as well as laser pulse properties in response to internal and external sensors data.

First claim

What is claimed is:

1. A method comprising:
producing a pulsed fanned beam of laser light;
driving a transmit scanning mirror and a receive scanning mirror to synchronously move such that the transmit scanning mirror scans the pulsed fanned beam of laser light in two dimensions over a plurality of measurement points in a field of view and the receive scanning mirror directs reflected light energy from the plurality of measurement points in the field of view onto an array of light sensitive devices;
measuring times-of-flight of pulses received by the array of light sensitive devices to create a point cloud;
detecting a feature in the point cloud; and
modifying the driving of the transmit scanning mirror and the receive scanning mirror to modify the synchronous movement of the transmit scanning mirror and receive scanning mirror in response to the feature, wherein the modifying of the driving of the transmit scanning mirror and the receive scanning mirror maintains the synchronous movement of the transmit scanning mirror and the receiving scanning mirror such that the transmit scanning mirror continues to scan the pulsed fanned beam of laser light in the two dimensions over the plurality of measurement points in a field of view while the receive scanning mirror continues to direct reflected light energy from the plurality of measurement points in the field of view onto an array of light sensitive devices while the driving is modified.

2. The method of claim 1 wherein modifying the driving of the transmit scanning mirror and the receive scanning mirror to modify the synchronous movement of the transmit scanning mirror and receive scanning mirror in response to the feature comprises modifying angular extents of mirror deflection of the transmit scanning mirror and the receive scanning mirror.

3. The method of claim 2 wherein modifying angular extents of mirror deflection of the transmit scanning mirror and the receive scanning mirror comprises modifying horizontal angular extents of mirror deflection.

4. The method of claim 2 wherein modifying angular extents of mirror deflection of the transmit scanning mirror and the receive scanning mirror comprises modifying vertical angular extents of mirror deflection.

5. The method of claim 1 wherein modifying the driving of the transmit scanning mirror and the receive scanning mirror to modify the synchronous movement of the transmit scanning mirror and receive scanning mirror in response to the feature comprises modifying an angular offset of mirror deflection of the transmit scanning mirror and the receive scanning mirror.

6. The method of claim 5 wherein modifying an angular offset of mirror deflection of the transmit scanning mirror and the receive scanning mirror comprises modifying a horizontal angular offset of mirror deflection.

7. The method of claim 5 wherein modifying an angular offset of mirror deflection of the transmit scanning mirror and the receive scanning mirror comprises modifying a vertical angular offset of mirror deflection.

8. The method of claim 1 wherein detecting a feature comprises detecting an object in the field of view.

9. The method of claim 1 wherein detecting a feature comprises detecting a traffic lane.

10. The method of claim 1 wherein detecting a feature comprises detecting a horizon.

11. A method comprising:
producing a pulsed fanned beam of laser light;
driving a transmit scanning mirror and a receive scanning mirror to synchronously move such that the transmit scanning mirror scans the pulsed fanned beam of laser light in two dimensions over a plurality of measurement points in a field of view and the receive scanning mirror directs reflected light energy from the plurality of measurement points in the field of view onto an array of light sensitive devices;
measuring times-of-flight of pulses received by the array of light sensitive devices to create a point cloud;
receiving vehicle sensor data; and
modifying the driving of the transmit scanning mirror and the receive scanning mirror to modify the synchronous movement of the transmit scanning mirror and receive scanning mirror in response to the vehicle sensor data, wherein the modifying of the driving of the transmit scanning mirror and the receive scanning mirror maintains the synchronous movement of the transmit scanning mirror and the receiving scanning mirror such that the transmit scanning mirror continues to scan the pulsed fanned beam of laser light in the two dimensions over the plurality of measurement points in a field of view while the receive scanning mirror continues to direct reflected light energy from the plurality of measurement points in the field of view onto an array of light sensitive devices while the driving is modified.

12. The method of claim 11 wherein modifying the driving of the transmit scanning mirror and the receive scanning mirror modify the synchronous movement of the transmit scanning mirror and receive scanning mirror in response to the vehicle sensor data comprises modifying angular extents of mirror deflection of the transmit scanning mirror and the receive scanning mirror.

13. The method of claim 11 wherein modifying the driving of the transmit scanning mirror and the receive scanning mirror modify the synchronous movement of the transmit scanning mirror and receive scanning mirror in response to the vehicle sensor data comprises modifying an angular offset of mirror deflection of the transmit scanning mirror and the receive scanning mirror.

14. The method of claim 11 wherein modifying the driving of the transmit scanning mirror and the receive scanning mirror modify the synchronous movement of the transmit scanning mirror and receive scanning mirror in response to the vehicle sensor data comprises modifying the synchronous movement of the transmit scanning mirror and receive scanning mirror in response to vehicle speed data.

15. The method of claim 14 wherein modifying the synchronous movement of the transmit scanning mirror and receive scanning mirror comprises reducing angular extents of mirror deflection as speed increases.

16. The method of claim 11 further comprising modifying laser light pulse properties in response to the vehicle sensor data.

17. A method comprising:
producing a pulsed fanned beam of laser light;
driving a transmit scanning mirror and a receive scanning mirror to synchronously move such that the transmit scanning mirror scans the pulsed fanned beam of laser light in two dimensions over a plurality of measurement points in a field of view and the receive scanning mirror directs reflected light energy from the plurality of measurement points in the field of view onto an array of light sensitive devices;
measuring times-of-flight of pulses received by the array of light sensitive devices to create a point cloud;
modifying the driving of the transmit scanning mirror and the receive scanning mirror to modify the synchronous movement of the transmit scanning mirror and receive scanning mirror, wherein the modifying of the driving of the transmit scanning mirror and the receive scanning mirror maintains the synchronous movement of the transmit scanning mirror and the receiving scanning mirror such that the transmit scanning mirror continues to scan the pulsed fanned beam of laser light in the two dimensions over the plurality of measurement points in a field of view while the receive scanning mirror continues to direct reflected light energy from the plurality of measurement points in the field of view onto an array of light sensitive devices while the driving is modified; and
modi

Assignees

• Microvision Inc

Inventors

• Morarity Jonathan A
• Nothern Iii Alga Lloyd
• Nonn Thomas
• Sharma Sumit

Classifications

• G01S7/4817 Primary

  relating to scanning · CPC title

• G01S7/4811

  common to transmitter and receiver · CPC title

• G01S17/10

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

• G01S17/931 Primary

  of land vehicles · CPC title

• G01S17/42

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