Fresnel Lens Solar Concentrator Design and Spectral Distribution on Focus Surface

It is necessary to analysize the spectral distribution of sun light on focal spot as well as its condenser ratio, both in the study of the different quantum efficiency of photoelectric materials and the different spectral absorption coefficient for the laser medium. Based on the absorption spectrum of Cr/Nd:YAG ceramic, this paper addresses itself to the study of convex Fresnel lens focus solar light and choose spectrum. Set Parameters which are used for the design of Fresnel lens such as the ring width, height the focal length as well as the design of spectrum can be changed and the spectral ditribution on focal plane can be controlled. By way of simulation, a method through which is the best optical design for matching Cr/Nd: YAG ceramic absorption spectrum can be found. The maximum absorb power density in six optimum design is 288.5W/cm(2), which is 3.2-18.5% higher than absorb power density in six initial design based on purpose of obtaining the maximum power density. (C) 2011 The Japan Society of Applied Physics