polaroid

OBS: Polariseur constitué par des cristaux synthétiques microscopiques ayant tous la même orientation.
OBS: Les cristaux fixés sur la gélatine d'un film sont montés sous verre.

OBS: A trademark name for a ""polarizer"" that consists of a sheet of cellulose that is impregnated with crystals of quinine iodosulphate. The crystals are aligned so that their optical axes are parallel, and they polarize light in two directions at right angles: in one direction most visible light is absorbed, and in the other, essentially white light is transmitted.