Abstract: An optical system has a correction half-sphere lens having multiple secondary mirrors mounted on an outer periphery of the correction half-sphere lens. A primary half-sphere mirror is coaxial and shares a same curvature center with the correction half-sphere lens. The primary half-sphere mirror has multiple through holes each corresponding to one of the secondary mirrors and having a second correction lens received therein to receive light from the corresponding secondary mirror. A cap is provided on top of the primary half-sphere mirror and has a shutter in a center of the cap to control incident light coming to the system.