Optical in-situ analysis of secondary reflectors in solar tower plants

An optical measurement for radiation concentrators is proposed. A Lambertia n light source is placed in the exit aperture of the concentrator. By takin g pictures of the concentrator as seen from a remote location one gets the transmission patterns which carry the information of transmission with the four-dimensional resolution of the phase space of geometric optics. By matc hing ray tracing simulations to the measurement, one can achieve detailed a nd accurate information about the geometry of the concentrator. The reflect ivity can be inferred by very simple means with 2% accuracy. This method ha s the potential to provide a handy tool to get automatically all optical in formation about a real size concentrator in situ.