A small part of the absorbed light energy in the photosynthesis process is lost during the migration from the pigment antenna to the reaction centers and are dissipated by a number of non-photochemical processes, including heat, and re-emission of a small but easily detectable amount (2-5% in vivo) of the absorbed radiation. This re-emission occurs at longer wavelengths in the red and far-red spectral regions and is termed as Chlorophyll Fluorescence (ChlF) (Shreiber, 1983; Backer & Bradbury, 1981)
