Found 2 items, similar to collimator.
English → English (WordNet) Definition: collimator collimator n 1: a small telescope attached to a large telescope to use in setting the line of the larger one 2: optical device consisting of a tube containing a convex achromatic lens at one end and a slit at the other with the slit at the focus of the lens; light rays leave the slit as a parallel beam
English → English (gcide) Definition: Collimator Collimator \Col"li*ma`tor\, n. 1. (Astron.) A telescope arranged and used to determine errors of collimation, both vertical and horizontal. --Nichol. [1913 Webster] 2. (Optics) A tube having a convex lens at one end and at the other a small opening or slit which is at the principal focus of the lens, used for producing a beam of parallel rays; also, a lens so used. [1913 Webster]