| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical encoder for performing appropriate measurement even when any abnormality occurs in a signal output from a light receiving element array. <P>SOLUTION: A optical encoder comprises: a scale; a light source; a plurality of light receiving element arrays 51 to 53 for receiving a light via the scale; and a measurement means 54. The light receiving element arrays 51 and 53 are respectively divided into two areas 511, 512, 531 and 532. The measurement means 54 comprises: an abnormality determining part 541 for determining whether or not any abnormality occurs in the areas 511, 512, 531 and 532 based on signals output from the areas 511, 512, 531 and 532; and a position measuring part 542 for measuring the position of the scale based on signals output from the areas 511, 512, 531 and 532, where it is determined that any abnormality does not occur by the abnormality determination part 541, and the light receiving element array 52. <P>COPYRIGHT: (C)2012,JPO&INPIT |
