ENCODER, MOTOR WITH ENCODER, AND SERVO SYSTEM

摘要

[Problem] To provide an encoder that has a simple configuration and that can be made smaller, a motor with an encoder, and a servo system. [Solution] An encoder comprises: a disc (110) fixed to a shaft (SH); a first slit (Sa) that is disposed on the disc (110) in a portion in the circumferential direction (C) around the center of rotation (O) of the disc (110) and that is configured so as to reflect light; a light source (121) that is substantially disposed on the axis of rotation (AX) of the shaft (SH) and that emits light onto a region that encloses at least the rotational track, by way of rotation of the disc (110), of the first slit (Sa); and a plurality of first light receiving elements (Pa) that are arranged along the circumferential direction (C) around the axis of rotation (AX) and that are configured to receive light that is reflected by the first slit (Sa).