(EN) Disclosed is an optical unit wherein a rotating reflector (26) rotates in one direction with a rotating axis at the center, while reflecting light emitted from a light source. The rotating reflector (26) is provided with a reflecting surface such that the light reflected by the rotating reflector, while rotating, forms a desired light distribution pattern, said light having been emitted from the light source. The light source is composed of light emitting elements. The rotating axis is provided within a plane that includes an optical axis and the light source. The rotating reflector (26) is provided with, on the periphery of the rotating axis, a blade that functions as the reflecting surface.