Servo motor and encoder are two important parts in servo motor control system. This rotary encoder is small in size. But its resolution is high. Single turn resolution reaches to 21 bit; multi-turn resolution reaches to 32 bit max. The motor encoder is necessary part of servo motor. The encoder resolution decides the precision of servo motor angle, position and speed measurement. Incremental type motor encoder has been widely applied in servo motor system. But for high resolution requirement industry, absolute type servo motor encoder is required more and more.