VCSEL (Vertical Cavity Surface Emitting Laser) is a semiconductor laser. VCSEL chip, as the core device of 3D imaging and sensing system, has blossomed everywhere in the intelligent information era. VCSEL is emitted perpendicular to the top surface. Compared with traditional IRLED and EEL semiconductor chips, as illustrated in Figure 1-1, VCSEL is characterized by small divergence angle, low temperature drift and low cost, and is widely used in 3D sensing, data communication, LiDAR and the like field. It can be said that VCSEL is the core component of the intelligent world.