Patent ID: 8422093
Filing Date: 2013-04-16
Classification: G02B,H04N

Abstract:
1. A light projection unit, comprising: a substrate; a plurality of light emitting elements arrayed on the substrate in a main scanning direction, each of the light emitting elements including a light emitting surface to project light; a light guide disposed facing the light emitting surfaces of the light emitting elements, to direct light projected from the light emitting elements onto an illumination area of an illumination target, the light guide including a first positioning portion; a holder including a second positioning portion to engages the first positioning portion of the light guide, to position the light guide on the holder, the first positioning portion of the light guide being positioned between centers of light emission of adjacent light emitting elements in the main scanning direction of the substrate when the first positioning portion engages the second positioning portion of the holder; and a cover configured to cover the substrate and the light guide and configured to fix the light guide in place, the light emitting elements being attached to the substrate such that the light emitting surfaces of the light emitting elements are perpendicular to the substrate, the holder further including a first surface on which the substrate is held, a second surface facing the light guide, and a step portion provided between the first surface and the second surfacer such that when the substrate is held on the first surface, the second surface is closer to the light guide than to the substrate, the light emitting element side of the light guide being positioned on the holder facing the substrate, and the cover being configured to cover the substrate held by the holder and the light guide positioned relative to the holder and configured to contact and press the light emitting element side of the light guide against the substrate to fix the light guide in place.