This page is optimized for large screens. Zooming may cause some display problems.

glossary

Isotropic light source: light source emitting with a constant intensity whichever the direction
Intensity ( radiometry ): power emitted by a light source per unit of solid angle ; same term used in photometry
Refraction index: for a transparent medium, ratio between the light speed in the air and the light speed in the medium ; for a reflective surface in the air or vacuum, the refraction index is « - 1 »
Transmission: ratio between transmitted radiation power (or intensity or amplitude) and incident radiation power (or intensity or amplitude)