Solar simulators are essential tools in fields such as photovoltaic research, materials science, and optical testing. For many years, xenon lamp–based solar simulators have been widely used as reliable light sources for reproducing sunlight under laboratory conditions. In recent years, LED-based solar simulators have also emerged and are increasingly used in various research environments.
From SAN-EI’s perspective, these two technologies should not be viewed as competing approaches. Instead, they represent complementary technologies that support different experimental objectives and together expand the possibilities of solar simulation.
Xenon solar simulators reproduce sunlight using a continuous-spectrum light source. Because their emission closely resembles natural sunlight over a wide wavelength range, xenon systems provide high spectral fidelity and broad spectral coverage. For this reason, they are widely used in photovoltaic device characterization and in measurements that must comply with international standards such as IEC and ASTM.
LED solar simulators, in contrast, generate a solar-like spectrum by combining multiple LEDs with discrete wavelengths. This approach provides flexibility in spectral control and can offer excellent temporal stability. LED systems can be advantageous in experiments that require programmable spectral conditions or rapid modulation of light intensity.
At the same time, the spectral structure of LED sources is fundamentally different from that of continuous light sources. Because LEDs produce discrete spectral peaks, they may not fully reproduce the continuous nature of sunlight across a wide wavelength range.
For these reasons, SAN-EI believes that the future of solar simulation lies in the coexistence of xenon and LED technologies. By selecting the appropriate light source according to the purpose of the experiment, researchers and engineers can create more reliable and versatile testing environments.