A type of solar radiation with wavelengths between 280-400 nm. It ends where the colors of rainbow start. The atmosphere absorbs all UV-C (< 280 nm), a significant part of UV-B (280 – 315 nm) but transmits most
of the UV-A radiation (315 – 400nm). UVR represents only about 7-9 % of total solar radiation reaching the biosphere, but unlike other types of solar radiation, UVR is highly energetic radiation. This means that
UVR can cause reactions between molecules that are hit by such radiation. This then helps with stimulating morphogenic responses in plants.
· UVA, or near UV (315–400 nm)
· UVB, or middle UV (280–315 nm)
· UVC, or far UV (180–280 nm)
One of the most important metrics for evaluating quality of the intensity of light at any given point below the luminaire. This can be used in the field on the plant canopy or from a single system to understand light spread and intensity and different mounting heights.