Structured light projection module based on VCSEL array light source

A depth camera, comprising:

• a structured light projection module configured to project a structured light pattern onto a target, wherein the structured light projection module comprises:
• a Vertical-Cavity Surface-Emitting Laser (VCSEL) array light source comprising a semiconductor substrate and at least two VCSEL sub-arrays, wherein the at least two VCSEL sub-arrays are arranged on the semiconductor substrate, and each of the at least two VCSEL sub-arrays includes VCSEL light sources;
• and
• a diffractive optical element (DOE) comprising at least two DOE sub-units, wherein the at least two DOE sub-units correspond to the at least two VCSEL sub-arrays respectively, and the at least two DOE sub-units are configured to project multiple copies of light beams emitted by the corresponding at least two VCSEL sub-arrays,
• wherein the at least two DOE sub-units include a first DOE sub-unit and a second DOE sub-unit, wherein the first DOE sub-unit splits the light beams of a first corresponding VCSEL sub-array into a first number of first split light beams, and the second DOE sub-unit splits the light beams of a second corresponding VCSEL sub-array into a second number of second split light beams, and wherein the first number of the first split light beams is greater than the second number of the second split light beams,
• wherein each of the second split light beams is brighter than each of the first split light beams, and
• wherein the first split light beams and the second split light beams are respectively projected outward by the first DOE sub-unit and the second DOE sub-unit to a substantial same field of view;
• an acquisition module configured to collect a structured light pattern reflected by the target;
• and
• a processor configured to calculate a depth image based on the collected structured light pattern.