biprism

WORDNET DICTIONARY

biprism(n = noun.artifact) Array - an optical device for obtaining interference fringes; Array

has parts: optical prism, prism

biprism, n. [Pref. bi- + prism.].

A prism whose refracting angle is very nearly 180 degrees. [Webster 1913 Suppl.]
A combination of two short rectangular glass prisms cemented together at their diagonal faces so as to form a cube; -- called also optical cube. It is used in one form of photometer. [Webster 1913 Suppl.]

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