The encoder is a device that converts the change of the physical quantity of the mechanical angle into an electrical signal; in the classification of the sensor, it belongs to the angular displacement sensor. According to this characteristic of the encoder, the encoder is mainly used to measure the angular displacement, angular velocity, and angular acceleration of the rotating object. These physical quantities are converted into electrical signals by the encoder and output to the control system or instrument. The control system or instrument is based on these quantities. To control the drive