| 摘要 |
PROBLEM TO BE SOLVED: To provide a rotary encoder that is advantageous in view of measurement accuracy.SOLUTION: A rotary encoder comprises: a cylindrical element including a cylindrical surface on which a plurality of marks are cyclically arrayed along the circumferential direction and rotating around the axis of the cylindrical surface as an axis of rotation; a detector including a light source for emitting light toward the cylindrical surface and a plurality of photoelectric conversion elements, the detector detecting a prescribed number of marks among the plurality of marks with the light emitted from the light source by using the plurality of photoelectric conversion elements; and a signal processing unit for obtaining the rotation angle of the cylindrical element on the basis of the output of the detector. The detector outputs a cyclic signal having a plurality of unequal cycles and corresponding to the prescribed number of marks. The signal processing unit obtains the rotation angle on the basis of the cyclic signal and data having a plurality of unequal cycles obtained on the basis of the geometric arrangement of the light source, cylindrical surface, and detector and a reference phase. |
