A transmissive optical encoder chip converts an object's motion into electronic signals by interrupting the light between an emitter and a receiver using a code disc. It is used for precise measurement of an object's position and speed.

A reflective optical encoder chip is a sensing device used for detecting position, angle, or speed. It has wide applications in fields such as industrial automation, robotics, and precision instruments.

Reflective/through-beam optical sensor chips can accurately monitor the presence and changes of objects within the measured area, making them an indispensable component on production lines.