Full or modified solar spectrums
The irradiance of the Sun at the Earth’s surface varies under different conditions due to absorption and scattering effects in the atmosphere, and so a number of other constants are important in regards to the irradiance of a solar simulator.
Depending on the atmospheric depth and solar angles, the reference solar spectrum can have different spectral variations. An air mass filter is commonly used to simulate the spectral irradiance of the reference solar spectrum.
Below the atmosphere the radiation emitted from the Sun can be divided into two components: direct radiation that comes from the Sun itself, and scattered radiation coming from the rest of the sky, including a portion reflected back from the ground. Solar simulators are adjusted to imitate the spectral distribution of sunlight for a variety of environments; to do this the spectral distribution from the xenon arc lamp source is altered and refined using Air Mass (AM) filters.
When discussing filters, the direct radiation spectrum is imitated using a direct (D) filter, and the total including scattered sky and ground radiation is matched by using a global (G) filter that imitates both components together.
AM1.5G ASTM E927 Solar spectrum according to standard classification for Solar Simulators for Electrical Performance Testing of Photovoltaic Devices
Most Sciencetech solar simulators use xenon arc lamps, which enables the system to produce a collimated beam of light, similar to that of a 5.8K blackbody, as the sun. AM1.0, 1.5 and 2.0 filters further modify the visible and UV portions of the spectrum for different sea-level conditions, and coupled with the use of high pressure Xenon arc lamps Sciencetech produces Class A standards for our solar simulators.
Sciencetech Engineering has the capability to adjust the solar spectrum for various conditions such as:
• Full solar spectrum in accordance with ASTM, IEC, and other standards
• Various portions of the solar spectrum (UV/VIS/IR portions)
• Different terrestrial spectrums (AM1.5G, AM1.5D, AM1.0G etc.)
• Extraterrestrial (space) solar spectrum (AM0)
• Special spectral filters to accommodate different spectral requirements