Innovative design of cassegrain solar concentrator system for indoor illumination utilizing chromatic aberration to filter out ultraviolet and infrared in sunlight

Many applications and related studies of solar energy have been focused on guiding sunlight into the indoors for illumination purposes. To achieve this objective, one of the approaches is the use of a high efficiency solar concentrator based on cassegrain construction with sun tracking system. However, exposure to UV in sunlight has been proved to be hazardous to humans, and the heat content of IR degrades illumination quality. In order to solve the two problems, we develop an innovative cassegrain solar concentrator system utilizing the theory of chromatic aberration by a chromatic lens to reduce UV and IR. A dispersion model to consider the impact between the chromatic lens and a guiding fiber is also proposed. As a result, the system can filter out UV completely and reduce IR by half. Further, the chromaticity coordinates of collected light for illumination is almost equal to sunlight, and the color difference is so small that the two appear equal to the human eye.