Patent ID: 8616706
Filing Date: 2013-12-31
Classification: G02B,G03B,H04N

Abstract:
1. An illumination device comprising: a first light source including a first solid light-emitting element, which emits light from a light-emission region configured of a single or a plurality of light-emission spots; a first beam spread angle changing element that changes a beam spread angle of light incident from the first light source; an integrator that equalizes an illuminance distribution of light in a predetermined illuminated region illuminated with light having passed through the first beam spread angle changing element; and a first small-amplitude oscillation element disposed between the first light source and the first beam spread angle changing element or between the first beam spread angle changing element and the integrator, and that changes, from time to time, an illumination state in the illuminated region, wherein, the first solid light-emitting element includes a laser diode, the integrator is configured of a first fly-eye lens and a second fly-eye lens, the first fly-eye lens being where light from the first beam spread angle changing element enters, the second fly-eye lens being where light from the first fly-eye lens enters, optical magnification of an optical system comprised of the first beam spread angle changing element and the first and second fly-eye lenses, and a shape of the first small-amplitude oscillation element are such to allow a size of each light source image formed on the second fly-eye lens by each cell of the first fly-eye lens not to exceed a size of one cell of the second fly-eye lens, and an amount of displacement of each light source image by oscillation amplitude of the first small-amplitude oscillation element is such not to form the light source image over a plurality of cells of the second fly-eye lens.