LED array to simulate the solar near-ultraviolet spectrum outside the Earth’s atmosphere

To assess the feasibility of a light emitting diode (LED) solid-state lamp that mimics the extraterrestrial solar near ultraviolet (NUV) spectrum between 250 and 400 nm, we present the design and experimental results of a prototype LED solar simulator. It consists of a matrix of 109 LEDs, selected based on wavelength, emission angle, and radiative power, in order to mimic the solar NUV spectrum outside the Earth’s atmosphere, with irradiance ranging from one to four times that of solar radiation. Such an LED lamp is suitable, for example, for testing the resistance of space materials to the NUV radiation. Based on our experimental tests, we analyze the advantages and drawbacks of the multichannel NUV LED solar simulator compared to traditional arc-lamps-based simulators.