| 摘要 |
<p>Out of phase electrical signal generation has photoelectric scanning system comprising two gratings displaced relative to each other. The image of the gratings is formed in succession. The pupil of the imaging system (4) used for the gratings (3, 6) is divided. A phase plate (10) producing a different phase effect of individual diffraction orders is arranged in each part pupil. A photoelectric receiver (9A to 9C) is assigned to each part pupil in a picture of the pupil. The phase plate (10) is designed in steps or wedges. The light points are arranged in a plane and are utilized for the generation of four out of phase signals.</p> |
