US 9,128,190 B1Granted

Light steering device with an array of oscillating reflective slats

AssigneeGoogle Inc.

InventorsDrew Ulrich, Pierre-yves Droz, Samuel Lenius

Life of this patent

Estimating the term…

Loading patent…

Abstract

A light detection and ranging (LIDAR) device scans through a scanning zone while emitting light pulses and receives reflected signals corresponding to the light pulses. The LIDAR device scans the emitted light pulses through the scanning zone by reflecting the light pulses from an array of oscillating mirrors. The mirrors are operated by a set of electromagnets arranged to apply torque on the mirrors, and an orientation feedback system senses the orientations of the mirrors. Driving parameters for each mirror are determined based on information from the orientation feedback system. The driving parameters can be used to drive the mirrors in phase at an operating frequency despite variations in moments of inertia and resonant frequencies among the mirrors.

Claims20

Dependent claims

A light detection and ranging (LIDAR) device comprising:

a plurality of mirrors arranged to rotate about respective axes of rotation parallel to a reflective surface of the respective mirrors, and wherein the axes of rotation of the plurality of mirrors are arranged to be aligned in parallel and in a common plane;
a plurality of electromagnets arranged to attract the plurality of mirrors via induced magnetic fields generated in the mirrors so as to apply torque on the respective mirrors about their respective axes of rotation, wherein each of the plurality of electromagnets is arranged to apply torque to only one of the plurality of mirrors such that each of the plurality of mirrors is associated with a mirror-associated set of electromagnets in the plurality of electromagnets;
a plurality of driving circuits for operating the plurality of electromagnets using a plurality of driving signals, wherein each driving circuit is configured to receive a respective input and generate, based on the respective input, a respective driving signal for operating a respective mirror-associated set of electromagnets;
a plurality of detectors configured to detect orientations of the plurality of mirrors;
a controller configured to:
(i) receive data from the plurality of detectors indicative of detected orientations of the plurality of mirrors, (ii) determine, based on the detected orientations, driving parameters sufficient to cause the plurality of driving circuits to operate the plurality of electromagnets such that the plurality of mirrors oscillate in phase at an operating frequency, and (iii) provide the determined driving parameters as input to the plurality of driving circuits;
and
a light source configured to emit light pulses directed toward the plurality of mirrors such that the light pulses are reflected by the plurality of mirrors.

5 more elements

Dependencies are inferred from the claim text.

Facts

Application: 14/090,485Filed 26 Nov 2013 · us provisional application
Priority: 6 Mar 2013
Granted: 8 Sep 2015
Term ends: Not estimatedThe source records don’t support an estimate.

Classification14 codes

G05D 1/0231
Specially adapted to land vehicles: using optical position detecting means
G01S 7/4815
Of transmitters alone: using multiple transmitters
G01S 7/4817
Constructional features, e.g. arrangements of optical elements: relating to scanning
G01S 17/42
Systems determining position data of a target: simultaneous measurement of distance and other co-ordinates