US 11,796,640 B2
Time-of-flight depth camera with low resolution pixel imaging
Matthew John Lawrenson, Eindhoven (NL); Joachim Wilhelm Hellmig, Ulm (DE); Holger Joachim Moench, Ulm (DE); Nicholas Walker, Eindhoven (NL); and Jan Jasper Van Den Berg, Eindhoven (NL)
Assigned to TRUMPF PHOTONIC COMPONENTS GMBH, Ulm (DE)
Filed by TRUMPF Photonic Components GmbH, Ulm (DE)
Filed on Mar. 2, 2020, as Appl. No. 16/805,887.
Application 16/805,887 is a continuation of application No. PCT/EP2018/073219, filed on Aug. 29, 2018.
Claims priority of application No. 17188935 (EP), filed on Sep. 1, 2017.
Prior Publication US 2020/0217931 A1, Jul. 9, 2020
Int. Cl. G01S 7/481 (2006.01); G01S 17/894 (2020.01); G01S 7/484 (2006.01)
CPC G01S 7/4815 (2013.01) [G01S 7/484 (2013.01); G01S 17/894 (2020.01)] 11 Claims
OG exemplary drawing
 
1. A time-of-flight depth camera comprising:
a VCSEL array;
an optical arrangement;
an evaluator; and
a light detector comprising at least one detector pixel,
wherein the VCSEL array or the optical arrangement are arranged to provide different illumination patterns in a reference plane in a defined field-of-view of the time-of-flight depth camera,
wherein the light detector is arranged to detect the different illumination patterns,
wherein the evaluator is arranged to reconstruct a depth image of the field of view with a resolution of a predefined number of pixels P based on the detected different illumination patterns,
wherein a number of the detected different illumination patterns N is at least 5% of the predefined number of pixels P,
wherein the VCSEL array is an addressable VCSEL array,
wherein the VCSEL array is arranged to provide different illumination patterns by addressing different VCSELs of the VCSEL array,
wherein the optical arrangement comprises a replicating optical structure,
wherein the replicating optical structure is arranged to replicate a light pattern provided by the VCSEL array across the illumination pattern such that the illumination pattern consists of two or more sub-illumination patterns,
wherein the detector is arranged such that each detector pixel detects a corresponding sub-illumination pattern,
wherein the number of detected different illumination patterns N is determined by a number of detector pixels D and a number of provided different illumination patterns, and
wherein the number of provided different illumination patterns is given by a product V*O of a number of different illumination patterns provided by the addressable VCSEL array V and a number of different illumination patterns provided by optical arrangement O, wherein V is chosen between 4 and 0.7*N, and wherein O is chosen between 2 and 0.7*N.