Spectral Characterization of Mini Concentrator Optics for its Use With MJ Cells

New concepts of concentrator modules have been proposed in the last years based on refractive optics and cost effective III-V devices at high concentration levels. The small size of the cells, the high concentration ratio and the compact aspect of the optics are some of the particular characteristics of these C-systems. In this paper we face out the optical characterization of these mini concentrator systems. A new method is proposed for indoor characterization of the spectrally dependent optical efficiency, which allows to obtain the integrated optical efficiency with any light spectrum and to calculate the electrical efficiency with multi-junction solar cells. Influence of the spectral transmittance of an optics on 2J cells current mismatch has been assessed