where "n"0 and "n"S are the refractive indices of the first and second media respectively. The value of "R" varies from 0 (no reflection) to 1 (all light reflected) and is usually quoted as a percentage. Complementary to "R" is the "transmission coefficient", or "transmittance", "T". If absorption and scattering are neglected, then the value "T" is always 1 − "R". Thus if a beam of light with intensity "I" is incident on the surface, a beam of intensity "RI" is reflected, and a beam with intensity "TI" is transmitted into the medium.