Silicon Nitride Optical Switch Array for Intensity‐Wavelength Encoded Structured Light Imaging

Abstract

Abstract Structured light (SL) imaging has become a cornerstone technology for high‐precision 3D perception in facial recognition, industrial robotics, and machine vision. However, existing systems face critical limitations, including susceptibility to ambient light interference, restricted eye‐safe power thresholds, and trade‐offs between resolution, range, and dynamic adaptability. In this work, a dual‐mode SL imaging system based on a Silicon Nitride optical switch array scanning chip is proposed. The system combines a 1 × 32 optical switch arrays with gradient‐periodic grating antennas to achieve beam steering: coarse scanning (0.65° step via channel switching) for fast imaging and fine continuous scanning (0.07° nm −1 via wavelength tuning) for details. This design eliminates mechanical components and lens alignment, enabling a 40°(H) × 20°(V) field of view while maintaining beam shaping and directed emission. Furthermore, the system achieves sub‐millimeter 3D ranging accuracy, demonstrated through scanning of planar and stepped surfaces, with root mean square errors of <360 and <900 µm. An intensity‐wavelength hybrid coding scheme is further applied to the 3D sensing system, which reconstructs high‐density point clouds (>200 pts cm −2 ) for a David at 1 m distance and complex scenes at 5 m distance. These advancements position the system as a transformative solution for 3D sensing in dynamic environments.