摘要 |
<p>An optical type position detecting device comprising a light source (14), and a light-receiving element (15) for detecting a light beam emitted by the light source, a region (20) on the light-receiving element (15) whereon the light beam is incident having parallel boundaries (20a,20b), the boundaries extending in directions substantially corresponding to directions of relative displacement of the region and the light-receiving element, the relative displacement accompanying a displacement of a body. The relative displacement can be detected by detecting a change in area of the region using the light-receiving element. A magnitude of displacement of the body is proportional to a change in output of the light-receiving element (15) since, irrespective of where the displacement of the body begins from, a constant width of the region is maintained along a direction perpendicular with respect to the direction of the relative displacement. In other words, the displacement of the body can be accurately detected since linearity is achieved between the two. <IMAGE></p> |