IMPROVED INTEGRATING-SPHERE THROUGHPUT WITH A LENS AND NONIMAGING CONCENTRATOR

A reflectometer design utilizing an integrating sphere with a lens and nonimaging concentrator is described. Compared with previous designs where a collimator was used to restrict the detector field of view, th e concentrator-lens combination significantly increases the throughput of the reflectometer. A procedure for designing lens-concentrators is given along with the results of parametric studies. The measured angu lar response of a lens-concentrator system is compared with ray-trace predictions and with the response of an ideal system. (C) 1995 Optical Society of America