OPTICAL DETECTION DEVICE, AND APPARATUS USING SAME

摘要

Each lens of a multi-segment lens is a Fresnel lens in which a second surface, being the reverse side surface of a first surface, has a plurality of lens surfaces. At least one of the plurality of lens surfaces is configured from a part of a side surface of an elliptical cone having a central axis oblique to a normal line of the first surface. Any normal line intersecting with the lens surface configured from the part of the side surface of the elliptical cone among normal lines of respective points on the first surface is non-parallel to a central axis of the elliptical cone corresponding to the lens surface with which the any normal line intersects.