Medical Term:

Bunsen-Roscoe law

Pronunciation: bŭn′sĕn ros′kō

Definition: in two photochemical reactions, the darkening of a photographic plate or film, if the products of the intensity of illumination and the time of exposure are equal, the quantities of chemical material undergoing change will also be equal; the retina for short periods of exposure obeys this law.

Synonym(s): reciprocity law, Roscoe-Bunsen law