Apparatus including a light-detecting element having a photo- electric conversion surface and an integral light blocking member

摘要

An apparatus for detecting information relating to displacement of an object on which a grating scale is affixed. The apparatus includes a beam- emitting system for irradiating the grating scale with a beam. The apparatus also includes a light-detecting element having a light- receiving surface. A grating portion is integrally formed on at least a part of the light-receiving surface for detecting a beam from the grating scale which is irradiated by the beam from the beam- emitting system. Information relating to displacement of the object is detected on the basis of the detection by the grating portion of the light-detecting element.