What is PAR (Photosynthetic Active Radiation)?
Understanding PAR Measurements
While PAR is often mistakenly referred to as a measurement of usable light, this term really only refers to a type of light. To understand how much PAR an LED grow light emits, look to measurements such as PPF and PPFD. PPF (Photosynthetic Photon Flux) communicates how much PAR a light emits. PPFD (Photosynthetic Photon Flux Density) measures the amount of PAR that reaches the canopy.