| 摘要 |
<p>The photo-electric linear measurement and movement detector consists of an array of photodiodes (16) arranged in a square grid pattern which is fixed to a stationary part of the machinery. A moving shutter is attached to a linkage and exposes or occludes the photosensitive elements in accordance with the linear displacement of the moving part of the machine. The sliding shutter has a sloping edge so that a complete line or part of a line of diodes is exposed or covered at any moment. A square-wave pulse generator (10) is used to scan each line of diodes so that a digital signal is produced which corresponds to the conduction state of each diode. Logic circuits (20) process the scanning signals from the photo-diode raster and a digital counter (30), displays the linear travel.</p> |
