Dictionary.com

focal plane

Save This Word!

noun Optics.
a plane through a focal point and normal to the axis of a lens, mirror, or other optical system.Compare principal plane.
the transverse plane in a telescope where the real image of a distant view is in focus.
QUIZ
TAKE JOY IN ACING THIS QUIZ ON “PRIDE” SYNONYMS
Hold your head up high as you embark on this quiz that explores some of the synonyms and meanings of “pride.”
Question 1 of 7
What does "dignity" mean?

Origin of focal plane

First recorded in 1890–95
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2022

How to use focal plane in a sentence

British Dictionary definitions for focal plane

focal plane

noun
the plane that is perpendicular to the axis of a lens or mirror and passes through the focal point
the plane in a telescope, camera, or other optical instrument in which a real image is in focus
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
FEEDBACK