| 摘要 |
PROBLEM TO BE SOLVED: To output an accurate encoder digital signal by a simple method, even if each center voltage of a plurality of periodical signals having different phases outputted from an encoder head is different. SOLUTION: This encoder having a scale 102 having an optical, magnetic or electrostatic displacement detection pattern, and an encoder head 101 for outputting at least two-phase encoder analog signals having different phases for detecting displacement caused by relative movement with the scale 102 by detecting a displacement detection pattern of the scale 102 is equipped with a center voltage detection part 107 for detecting only the center voltage of the encoder analog signal, and a reference value adjusting circuit 108 for adjusting the center voltage detected by the center voltage detection part 107 to agree with a prescribed reference voltage. COPYRIGHT: (C)2007,JPO&INPIT
|
