autocollimator

[aw-toh-kol-uh-mey-ter]

noun Optics.

an instrument combining the functions of a telescope and collimator, for detecting and measuring very small deviations in a beam of light.

Origin of autocollimator

auto-³ + collimator

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018