| 摘要 |
<p>An electro-optical sensor for use with a retro-reflective target (10) has light-emitting and -sensing assemblies mounted on opposite sides of a thin substrate (1) that acts as a light-screen between them. The light-emitting assembly involves a LED (4) and collimating and parallel lenses (2, 4) for fan-shape light-beam projection, and the sensing assembly involves a collecting lens (5), an aperture plate (6) and a photodiode array (7) with optional field-curvature correcting lens (8). The lens (5) is located abutting the substrate (1) within the aperture of plate (6), so that the entrance pupil of the light-collection optics and the exit pupil of the light-projection optics when viewed from the target (10) abut opposite, parallel straight-edges of the substrate (1). The photodiode array (7) may be a linear pixel array parallel to the substrate-surface, or may be replaced by a single, large-area photodiode with aperture-limitation of its field of view to a narrow fan-shape parallel to the substrate-surface. A plurality of light-emitters (77) with individual optics (78, 80) for projecting a plurality of merging beams may be used with photo-detectors (71) that have individual light-collection optics (72, 73) with merged fields of view. The sensor is applicable to sensing golf club-head (100) movement, and vehicle number-plate (116) and speed sensing.</p> |
