focal length


Definition of focal length

: the distance of a focus from the surface of a lens or curved mirror

Examples of focal length in a Sentence

Recent Examples on the Web There are three cameras on the new phone, and one of them has a variable focal length, 85-125mm. David Phelan, Forbes, 14 May 2022 Fine details may also be captured by using a zoom lens at a medium focal length. Deanna Chandra, San Diego Union-Tribune, 13 Nov. 2021 But at the right focal length, the image will be perfectly in focus in both directions, and that gives the cat an extra way of judging distance. Helen Czerski, WSJ, 22 Oct. 2021 The Smartphone For Snapdragon Insiders has an unusually high-resolution 24MP front-facing camera, with a 27mm (full-frame equivalent) focal length. Marco Chiappetta, Forbes, 20 Sep. 2021 For comparison, the S21 Ultra’s super telephoto lens has an equivalent focal length of 240mm. Mike Snider, USA TODAY, 9 Aug. 2021 Aperture is measured in f-stops, which is a ratio of the focal length divided by the size of the camera’s opening. Maren Estrada, BGR, 5 Aug. 2021 As the focal length narrows, the lens offers a wider view. Stephen J. Beard, USA TODAY, 7 May 2021 The liquid lens essentially has an outer coating that changes shape when hit with electrical currents, which allows the camera sensor to change focal length, too. Ben Sin, Forbes, 21 Apr. 2021 See More

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

First Known Use of focal length

1682, in the meaning defined above

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Time Traveler for focal length

Time Traveler

The first known use of focal length was in 1682

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Dictionary Entries Near focal length


focal length

focal plane

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Last Updated

24 May 2022

Cite this Entry

“Focal length.” Dictionary, Merriam-Webster, Accessed 25 May. 2022.

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More Definitions for focal length

focal length

\ -ˌleŋ(k)th How to pronounce focal length (audio) \

Medical Definition of focal length

: the distance of a focus from the surface of a lens or concave mirror symbol f

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