In this research, solar illumination is suggested to be used as an alternative to regular electrical illumination sources. Sunlight rays are collected, concentrated and transported through a system of light guide which distributes the sunlight to interior rooms. Schmidt Cassegrainin arrangement is used in the optical solar system design. Optical solar system consists of a tracking parabolic dish as a primary reflector, suggested to concentrate the solar rays on a secondary reflector, a cold mirror, which splits the solar spectrum into visible light which is reflected, directed into a plastic optical fiber cable, and infrared radiation which is transmitted away from the optical system to avoid melting the plastic optical fiber. An optimum optical design is attained by considering the optimum following parameters: applying different dish rim angles, different dish diameters and different dish reflector materials. Sun spot diameter to plastic optical fiber diameter ratio is a measure of geometrical compatibility of optimum transmitting solar light through the optical system.