The motor driving control of X-Y-Z table utilizing photoelectric device and optical pattern recognition

Position detectors which use the lateral photo effect are used for position detection and positioning on a X-Y-Z stage. Lasers (He-Ne, 632.8 nm) are used as light sources, and position sensing devices are used as light receptors. These devices are applied to absolute position detection on the X-Y-Z stage and to pattern recognition.<
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