In general, infrared components can be classified into two types, such as infrared illumination and laser applications, depending on the purpose of use. However, if they are further classified by the principle of illumination of different products, they can be divided into LEDs, EELs (edge-emitting lasers), and VCSELs. Three different types of products, because of their different light source characteristics, current and frequency performance, each has a corresponding terminal application market.

Since the LED component has a simple light-emitting principle, it only needs to provide a higher operating current to drive the light, but the emitted light is still a divergent light source, and generally can only provide general illumination, or is further used in a 2D sensing system.

The EEL and VCSEL light rays are laser light. The principle of light emission is slightly different from that of LED light generation. It is also necessary to use the material structure design to obtain laser light after multiple reflections.

As for the difference between EEL and VCSEL, it is based on the design of the EEL's own component structure. The beam angle and shape of the illuminating beam are larger and elliptical than the VCSEL component. Therefore, at this stage, it is only suitable to provide a light source such as a general laser pen; and the illuminating angle of the VCSEL component. It is more suitable for the development of 3D sensing technology products, and is further applied to mobile phone face recognition and vehicle light ranging ranging systems.