Natural Light Illumination System with the Prismatic Daylight Collector

In buildings, efficient lighting systems and excellent design of interior natural light illumination would contribute to energy saving by direct use solar energy for illumination. We proposed an open natural light illumination system which is compounded by a prismatic canopy as well as the daylight collector, a reflector for re-directing daylight and a diffuse reflector for illumination. The efficiency of sunshine illuminate on the surface of the right-angle prismatic collector at different incident angles on the performance of main emerged light was investigated using matrix ray tracing model and edge ray principle. It was also found that the distribution of main emerged light can be shifted by changing the tilt angle of the right prismatic collector. The directionality of main emerged light from S2 is applied to effort the performance of natural light illumination systems by simply guiding design. The prismatic daylight collector as well as the daylight canopy not only decrease the discomfort of glare, but also collect daylight for natural lighting system.