Rational Design of Scalable Solar Simulators With Arrays of Light-Emitting Diodes and Double Reflectors

In this article, we propose a new rational design of a scalable solar simulator with arrays of high-power light-emitting diodes (LEDs) and double reflectors: individual reflectors were used to minimize the required number of high-power LEDs, while common for multiple arrays mirror system ensures further light homogenization. Step-by-step ray-tracing simulations were applied to reveal the optimal layouts and features of LED arrays. Properties of two prototype solar simulators were measured experimentally to verify the validity of results obtained by semianalytical simulations and to demonstrate how properties of the solar simulators evolve by changing the design parameters. We demonstrate that only 22 LEDs can illuminate an area of 14 cm × 16 cm according to requirements for AAA class solar simulators in 400 to 1100 nm spectral range with this new simulator design. Such an area can fit industrial solar cells of up to 5 in. in diameter thus opening new industrial application possibilities for such small and robust LED arrays.