An optical projector system is provided. The optical projector system includes light source device, an optical system, a lens set, and a photoelectric conversion device. The optical system has a light entrance end corresponding to the light source device and a light exit end corresponding to the lens set. The light source device includes a light source and a hood enclosing the light source. The light source device, the optical system, and the lens set together form a light passage. The photoelectric conversion device is disposed on a deviating light zone outside the hood for receiving the light deviating from the light passage.