| 摘要 |
[Problem] To provide a reflective encoder with which it is possible to detect both amount of movement and direction of movement with a single output beam, and which is simple in construction, for high reliably and ease of miniaturization. [Solution] Provided is a reflective encoder in which an output beam outputted from a laser oscillator impinges upon a reflective diffraction grating situated on the scale side, and diffracted light outputted by the reflective diffraction grating is received by a photoreceptor unit, wherein an interference optical system is situated between the photoreceptor unit and the reflective diffraction grating, so that there can be constructed an optical system with which it is possible to measure both the amount of movement and the direction of movement of the scale, with a single output beam. |
