| 摘要 |
An optical encoder includes a light source (310), a scale (200) which is irradiated by the light source (310) and has a fine pitch pattern and a coarse pitch pattern in a measuring direction in one track, a high resolution detection sensor array (311, 312) which receives light from the scale (200) and detects the fine pitch pattern, and a low resolution detection sensor array (311, 312) which receives light from the scale (200) and detects the coarse pitch pattern. A transmittance distribution or a reflectivity distribution of the scale (200) is a distribution obtained by summing up a modulation component which corresponds to the fine pitch pattern and in which integrated values in a direction perpendicular to the measuring direction form modulation amplitude uniform in the measuring direction and a modulation component which corresponds to the coarse pitch pattern and in which modulation amplitude is uniform in the measuring direction. |
