focal plane

noun

: 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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The ring turns smoothly with enough resistance to make precise changes to the focal plane, and shows no lag between action and focus drive. — PC Magazine, 9 Sep. 2025 From there, the system slowly changes its focal plane, moving through the stack and capturing images that include different layers of voxels. — ArsTechnica, 18 Feb. 2026 Traditional lenses are limited to sharpening one focal plane (the distance between an object and your camera) at a time, blurring everything behind or in front of that object. — Jess Weatherbed, The Verge, 29 Dec. 2025 Second focal plane scopes with MOA turrets and reticles still dominate the hunting market, however. — John B. Snow, Outdoor Life, 15 Jan. 2026 See All Example Sentences for focal plane

Word History

First Known Use

1840, in the meaning defined above

Time Traveler
The first known use of focal plane was in 1840

Rhymes for focal plane

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Browse Nearby Words

focal length
focal plane
focal-plane shutter
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Cite this Entry

“Focal plane.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/focal%20plane. Accessed 7 Jul. 2026.

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Medical Definition

focal plane

noun
: a plane that is perpendicular to the axis of a lens or mirror and passes through the focus
Last Updated: - Updated example sentences
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