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definitions

crown lens

noun Optics.
  1. a lens made of crown glass, usually used as the converging lens component of an achromatic lens.

Origin of crown lens

First recorded in 1825–35
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for crown lens

crown lens

noun
  1. a lens made of optical crown, esp the optical-crown part of a compound achromatic lens
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012