| 摘要 |
PROBLEM TO BE SOLVED: To provide a photoelectric encoder with a high operational stability capable of measurement of triaxial directions of the moving grating with a small size and at an economical price. SOLUTION: The six light beams 21a, 21b, 22a, 22b, 23a, 23b generated by the light beam 3 incident diffracted by the diffraction gratings 4A, 4B enter the moving grating 5. These light beams are diffracted by the moving grating 5 respectively, the light beams 21b, and 23b are emitted almost in the same direction and detected by the light receiving element A, the light beams 21a, 22b are emitted almost in the same direction and detected by the light receiving element B, and the light beams 22a, 23a are emitted almost in the same direction and detected by the light receiving element C. Based on the output signal of the light receiving elements A, B, and C, the operation for the phase information etc. of the intensity of the interference light is performed by the encoder processing circuit 7, and based on the phase information, the x-axis movement information, z-axis movement information on the moving grating 5 and pitch angle variation information can be acquired. COPYRIGHT: (C)2006,JPO&NCIPI
|
