Homogeneity and Lifetime Performance of a Tunable Close Match LED Solar Simulator

Our commitment is the development of an industrial-grade Class AAA solar simulator based on LED technology [1], . Presently, the LEDSim™ covers the full wavelength range of interest for Si-PV with an extension in the UV, matching AM1.5 g from 350 nm to 1100 nm. To achieve user-defined target spectra we apply 22 different LED packages including several uncommon types. We present a measured spectrum tuned to AM1.5 g. It follows from rare lifetime information for some LED species that we need to set a strong focus on reliability determination for our lightheads. In this paper we show how we confirm the lifetime promise of the LED technology with reliability testing. Modern design-for-reliability methods are taken into account in order to increase the reliability of the LEDSim™. Beam shaping and homogeneity are key functions of a sun simulator, and a large effort is made on achieving Class A homogeneity for each wavelength interval as specified in IEC 60904-9 [2]. We are testing different kinds of LED optics and add mirror channels to achieve the best relation between homogeneity and intensity.