focal plane


Definition of focal plane

: a plane that is perpendicular to the axis of a lens or mirror and passes through the focus

Examples of focal plane in a Sentence

Recent Examples on the Web Still, most new products in the riflescope category have traits that appeal to long-range shooters: first-focal plane reticles, tactical milling turrets, and ample adjustment ranges. Andrew Mckean, Outdoor Life, "Nikon Will No Longer Make Riflescopes," 20 Jan. 2020 The difference between focal planes becomes exaggerated at extremely close and far target distances—decreasing accuracy and obscuring the reticle. Michael R. Shea, Field & Stream, "The 10 Best Rimfire Scopes for Any Budget," 3 Jan. 2020 The instrument has 5000 fibers attached to its 0.8-meter-wide focal plane. Daniel Clery, Science | AAAS, "Robot detector to map cosmos for clues to dark energy," 11 Sep. 2019 Magic Leap theoretically features multiple focal planes that let your eyes focus more normally than with other mixed reality headsets. Adi Robertson, The Verge, "I tried Magic Leap and saw a flawed glimpse of mixed reality’s amazing potential," 8 Aug. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'focal plane.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of focal plane

1840, in the meaning defined above

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Time Traveler for focal plane

Time Traveler

The first known use of focal plane was in 1840

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Statistics for focal plane

Cite this Entry

“Focal plane.” Dictionary, Merriam-Webster, Accessed 12 Jul. 2020.

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More Definitions for focal plane

focal plane


Medical Definition of focal plane

: a plane that is perpendicular to the axis of a lens or mirror and passes through the focus

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Rhyming Dictionary: Words that rhyme with focal plane

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