Special Features:

Wedge scale graduated in degrees full circle, reticle scale graduated in minutes through 1 degree, angular position direct reading of 1 arc minute, angular deviation computed to 0.1 arc second, light source ge no.328 lamp (2 spares included), 115v power supply

Properties:

A transparent item with at least two polished plane surfaces inclined toward each other, designed for use in optical instruments to reflect and/or refract a beam of light. It may have one or more mirrored surfaces for greater reflection. Includes optical wedges used to divert paths of light by refraction, but to a lesser degree. See also beam splitter, optical instrument.