IES LS-3-20 (R2023)

An understanding of the physics of light makes clear how light stimulates the visual system and ultimately produces perceptions, how light interacts with materials to provide for its own control and distribution by luminaires, how light makes materials luminous and participates in the generation of color perceptions, how light is produced by electric light sources, and why light from the sun and sky can greatly enhance the quality of an interior environment. This document describes the physics of radiant energy for various light source types, as well as the physical optics used for manipulating light.