Patent ID: 7609746

Claim:
A light source device that generates irradiation light that is irradiated onto a predetermined face, the light source device comprising: a laser light source that emits laser light; a diffractive optical element that is located between the laser light source and the predetermined face, and that diffracts the laser light; a diffusion optical element that is located between the laser light source and the predetermined face, that is located between the diffractive optical element and the predetermined face, that has an incidence face into which the laser light is incident and a light emission face from which the laser light from the incidence face is emitted, and that diffuses the laser light; and unit structures that are two-dimensionally arrayed on at least one of the incidence face and the light emission face of the diffusion optical element, and that cause the light which is perpendicularly incident into the diffusion optical element to refract at one time, and then emit this light toward the predetermined face, wherein the laser light from the diffractive optical element is incident into the incidence face of the diffusion optical element.