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shadow mask

American  

noun

Television.

  1. a perforated metal plate situated behind the faceplate of a color television picture tube and having holes aligned to insure that each of three electron beams strikes only its corresponding red, green, or blue phosphor dot.

shadow mask British  

noun

  1. television a perforated metal sheet mounted close to the phosphor-dotted screen in some colour television tubes. The holes are positioned so that each of the three electron beams strikes the correct phosphor dot producing the required colour mixture in the image

"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

Etymology

Origin of shadow mask

First recorded in 1950–55

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.