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 Every photo and video contains metadata — file information that tells us the date and time the image was created, information about the make of camera, the focal length and sometimes the GPS coordinates. Dmitriy Khavin, New York Times, "A Civilian Camp in Syria Was Bombed. Here’s How We Traced the Culprit.," 1 Dec. 2019 This deal also includes a 50-250mm, giving you a huge focal length range in a small, two-lens setup. Wired, "The Best Camera and Photography Deals for Black Friday," 27 Nov. 2019 This tool allows you to enter GPS coordinates and camera/lens information, then pan around to experiment with what millimeter focal length would be the best from your location. Trevor Mahlmann, Ars Technica, "How to spot the SpaceX Starlink satellite train overhead this week," 13 Nov. 2019 More Soft Robots The activated soft elastomer works to increase focal length by as much as 32 percent. Daisy Hernandez, Popular Mechanics, "These Contact Lenses Zoom In and Out with the (Double) Blink of an Eye," 29 July 2019 But just about every high-end competitor now has two (if not more) cameras on the back of their flagship phones, and there are some things — like focal length — that just can’t be precisely recreated using software magic. Jacob Kastrenakes, The Verge, "Everything we think we know about the Pixel 4, from Google’s Pixel 4 reveal," 13 June 2019 Combined, Fujifilm says this gives the SX800 a total equivalent focal length of 1000mm, which is enough to focus on a car’s license plate from 1km or roughly 0.6 miles away. Jon Porter, The Verge, "Fuji’s first surveillance camera can read a license plate from 1km away," 24 July 2019 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,, "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

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.

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First Known Use of focal length

1682, in the meaning defined above

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Time Traveler for focal length

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The first known use of focal length was in 1682

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Cite this Entry

“Focal length.” Dictionary, Merriam-Webster, Accessed 23 Feb. 2020.

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More Definitions for focal length

focal length


English Language Learners Definition of focal length

technical : the distance from the surface of a lens to the point of focus (sense 3)

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

More from Merriam-Webster on focal length

Rhyming Dictionary: Words that rhyme with focal length Encyclopedia article about focal length

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