Atmospheric physics radiation (emitted by the sun) and terrestrial radiation (emitted by Earth's surface and atmosphere). Solar radiation contains variety of wavelengths. Visible light has wavelengths between 0.4 and 0.7 micrometers. Shorter wavelengths are known as the ultraviolet (UV) part of the spectrum, while longer wavelengths are grouped into the infrared portion of the spectrum. Ozone is most effective in absorbing radiation around 0.25 micrometers, where UV-c rays lie in the spectrum. This increases the temperature of the nearby stratosphere. Snow reflects 88% of UV rays, while sand reflects 12%, and water reflects only 4% of incoming UV radiation. The more glancing
Ultraviolet krypton provides resonantly enhanced tunable VUV covering from 100 nm to 200 nm. Practically, the lack of suitable gas/vapor cell window materials above the lithium fluoride cut-off wavelength limit the tuning range to longer than about 110 nm. Tunable VUV wavelengths down to 75 nm was achieved using window-free configurations. Lasers have been used to indirectly generate non-coherent extreme UV (EUV) radiation at 13.5 nm for extreme ultraviolet lithography. The EUV is not emitted by the laser, but rather by electron transitions in an extremely hot tin or xenon plasma, which is excited by an excimer laser. This technique does