The light visible to the human eye (approx. 380-780nm) is also used by plants. This part of the electromagnetic radiation, which powers photosynthesis, is named PAR and is usually found in wavelengths range 400 to 700nm.
For plant growers, biologists and scientists the most important data in the light requirements for plants is PPFD (photosynthetic photon flux density). PPFD is a measurement of the amount of light that actually reaches a plant (the number of photosynthetically active photons that fall on a given surface each second).
PPFD or Photosynthetic Photon Flux Density and
YPFD Yield Photo Flux Density
Illuminance - Lux
CRI - Color Rendering Index, R1- R15, Ra
CIE 1931 chromaticity (x,y) coordinates
CIE 1976 UVS (u' , v' ) coordinates
This instrument is equipped with LED Spectral Power Distribution (SPD), colorimetric parameters, PPFD, YPFD, two super-imposable standards (McCree1972, DIN5031-10-2000), and Super-imposable Chlorophyll-α, Chlorophyll-β, and Carotene-β with spectrum stack.