focal length
nounDefinition 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
Additionally, by blinking, the lenses can change their focal length, which amounts to being able to zoom in and out just as users do on their phones. — Maria Pasquini, PEOPLE.com, "Scientists Develop Robotic Contact Lenses That Let Users Zoom with the Blink of an Eye," 29 July 2019 All are almost guaranteed to have long focal lengths. — Andy Kessler, WSJ, "Stock Picking Is Like Time Travel," 13 Jan. 2019 The Sol, which is available starting today for $199.95, is available in a 45mm focal length for Canon EF, Nikon F, Sony A, Pentax K, Sony E, and Fuji X mounts, and a 22mm version for Micro Four Thirds. — Dan Seifert, The Verge, "Lensbaby’s new Sol lens makes quirky images," 7 Aug. 2018 There are currently 16 operational telescopes of different sizes that make up the LCO, ranging in focal length from 2 meters to 0.4 meters, with more telescopes planned. — Jay Bennett, Popular Mechanics, ""Brightest Supernova Ever" Turns Out to Be a Star Ripped Apart by a Supermassive Black Hole," 12 Dec. 2016 The shift from lens width to focal length likely arose in Hollywood for reasons of precision. — Allain Daigle, The Atlantic, "How the 50-mm Lens Became ‘Normal’," 13 May 2018 The comparison of normal vision with focal length, rather than other forms of measurement, persists because of how lenses came to be produced and used in standard practice. — Allain Daigle, The Atlantic, "How the 50-mm Lens Became ‘Normal’," 13 May 2018 In the 2016 tests, images were collected through conventional DSLR cameras set up for multiple focal lengths across both the visible and infrared spectra to simulate plenoptic capabilities. — Russell Brandom, The Verge, "New Homeland Security system will bring facial recognition to land borders this summer," 5 June 2018 Over time, though, lenses came to be measured by the distance of their focal length. — Allain Daigle, The Atlantic, "How the 50-mm Lens Became ‘Normal’," 13 May 2018These 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.
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More Definitions for focal length
focal length
nounEnglish Language Learners Definition of focal length
technical
: the distance from the surface of a lens to the point of focus (sense 3)
See the full definition for focal length in the English Language Learners Dictionary
focal length
noun
\ -ˌleŋ(k)th
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Medical Definition of focal length
: the distance of a focus from the surface of a lens or concave mirror
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