collimator

col·li·ma·tor  (kl-mtr)

n.

A device capable of collimating radiation, as a long narrow tube in which strongly absorbing or reflecting walls permit only radiation traveling parallel to the tube axis to traverse the entire length.

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collimator  (kl-mtr)

A device that turns incoming radiation, such as light, into parallel beams. Simple collimators consists of a tube having a narrow, variable slit at one end and a convex lens at the other. Radiation entering the tube through the slit exits the lens in the form of parallel beams. Collimators are used to establish focal lengths of lenses and to measure the distance of distant objects whose position is known. See illustration at spectroscope.

Thesaurus

Noun	1.	collimator - a small telescope attached to a large telescope to use in setting the line of the larger one telescope, scope - a magnifier of images of distant objects
	2.	collimator - 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 optical device - a device for producing or controlling light prism spectroscope, spectroscope - an optical instrument for spectrographic analysis