| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a rotary encoder whose resolution is improved.SOLUTION: A rotary encoder 1 comprises: a light source 2; a doveprism 3; a two-dimensional PSD 4; and an operation section 5, and measures the rotation angle of a rotor 6 rotating about the rotation axis. The light source 2 is eccentric with respect to the rotation axis and emits light having an optical axis parallel with the rotation axis. The doveprism 3 is disposed between the light source 2 and the two-dimensional PSD 4 so that the emitted light from the light source 2 enters the incidence plane. The doveprism 3 is fixed to the rotor 6 so that the central axis coincides with the rotation axis of the rotor 6.</p> |
