| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical encoder capable of achieving the reference of at least one measurement scale by preventing actual position measurement from being extremely disturbed.SOLUTION: A first scale 10 has a first measurement scale arranged so as to be movable along a first measurement direction and a spatially limited first mark 15 different from the first measurement scale in at least one predetermined position along the first measurement direction. A second scale 20 has a second measurement scale arranged so as to be movable along a second measurement direction and a second reference mark 25 in at least one position. Only when the first scale 10 exists at a predetermined position along the first measurement direction preliminarily set by the first mark 15, the second reference mark 25 is available for generating at least one reference signal at the reference position of the second scale 20. |
