US 12,241,741 B2
Laser sensor, system and method for self-mixing interferometry
Hans Spruit, Waalre (NL); Jochen Hellmig, Valkenswaard (NL); Stephan Gronenborn, Aachen (DE); Johannes Meyer, Stuttgart (DE); Andreas Petersen, Stuttgart (DE); and Thomas Schlebusch, Stuttgart (DE)
Assigned to TRUMPF PHOTONIC COMPONENTS GMBH, Ulm (DE); and ROBERT BOSCH GMBH, Stuttgart (DE)
Filed by TRUMPF Photonic Components GmbH, Ulm (DE); and Robert Bosch GmbH, Stuttgart (DE)
Filed on Apr. 27, 2022, as Appl. No. 17/730,220.
Claims priority of application No. 21171555 (EP), filed on Apr. 30, 2021.
Prior Publication US 2022/0349703 A1, Nov. 3, 2022
Int. Cl. G01B 9/02 (2022.01); G01S 7/4912 (2020.01); H01S 5/00 (2006.01)
CPC G01B 9/02092 (2013.01) [G01S 7/4916 (2013.01); H01S 5/0028 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A laser sensor, comprising:
a laser source configured to emit a laser beam,
optics configured to project the laser beam as a one-or two-dimensional patterned laser beam onto a surface of an object to be examined, such that a distance of the patterned laser beam from the laser source varies for different regions of the surface onto which the patterned laser beam is projected,
a detector configured to determine a self-mixing interference signal generated by laser light of the patterned laser beam reflected from the object back into the laser source, and
circuitry configured to analyze a single spectrum of the self-mixing interference signal and extract from the single spectrum of the self-mixing interference signal multiple frequencies indicative of at least one of the following: multiple distances of the different regions of the surface from the laser source, or multiple velocities of the different regions of the surface with respect to the laser source.