LIGHT APPARATUS OF AN OPTICAL MOUSE WITH AN APERTURE STOP AND THE LIGHT PROJECTION METHOD THEREOF

A light apparatus of an optical mouse with an aperture stop and the light projection method thereof are described. The light apparatus has at least one image-forming lens and an aperture stop. The image-forming lens defines an interior area and an external area. The aperture stop has a pupil. The aperture stop shelters the external area of the image-forming lens. The pupil of the aperture stop corresponds to the interior area. The present light apparatus will not produce a light halo on the image detection unit of the optical mouse when the light source of the optical mouse projects a light that passes through the image-forming lens of the light apparatus. Therefore, the image detection unit clearly detects the image of the image detection surface.