focal length

noun

: 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

Soderbergh restricts himself to a handful of prime lenses in the film, avoiding zooms and shooting at the wider focal lengths typical of the era; the result is that most scenes are carefully staged in relatively long master shots with multiple actors interacting in the frame. —Jim Hemphill, IndieWire, 4 Apr. 2025

The 12-28mm focal length covers a wide to standard angle of view on a DX camera, roughly the same as an 18-42mm full-frame zoom gets. —PC Magazine, 31 Mar. 2025

Four of them have a short focal length, which translates to a relatively wide field of view, while the other two have a longer focal length. —Mike Wall, Space.com, 13 Mar. 2025

Also, instead of a dedicated telephoto lens, the camera digitally crops into the 48MP sensor to create an optical-quality 2x zoom, effectively giving you a second focal length without adding a physical lens. —Jennifer Jolly, USA TODAY, 28 Feb. 2025

Word History

First Known Use

1682, in the meaning defined above

Rhymes for focal length

• strength

Kids Definition

focal length

noun

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

Medical Definition

focal length

noun

-ˌleŋ(k)th 

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

—symbol f