摘要:
A light irradiation device includes a laser light source configured to emit laser light; and a light diffusion member configured to convert the laser light into diffusion light. Light based on the laser light is emitted to an outside from a light output unit via an output optical path or two or more output optical paths including an optical path which the diffusion light passes through. The light diffusion member includes a diffusion optical path changing member configured to convert the laser light into the diffusion light and change an optical path. The output optical path does not include an optical path in which laser light emitted toward the diffusion optical path changing member goes straight at a light diffusion position according to the diffusion optical path changing member to go toward the light output unit.