f-number

(redirected from f-numbers)
Also found in: Encyclopedia.

f-num·ber

(ĕf′nŭm′bər)
n.
The ratio of the focal length of a lens or lens system to the effective diameter of its aperture. Also called f-stop.

f-number

or

f number

n
(Photography) photog the numerical value of the relative aperture. If the relative aperture is f8, 8 is the f-number and indicates that the focal length of the lens is 8 times the size of the lens aperture. See also T-number

f-number

(ˈɛfˌnʌm bər)

n.
a number corresponding to the ratio of the focal length to the diameter of a lens system, esp. a camera lens. Symbol: f/
[1890–95]
Translations

f-number

n (Phot) → Blende f, → Blendenzahl f
References in periodicals archive ?
The h-numbers of P are defined as a certain integer transformation of its f-numbers, and knowing the f-numbers of P is equivalent to knowing its h-numbers.
The Clear Align Featherweight(TM) INSPIRE(TM) line is a series of pre-engineered, high-performance, SWIR lenses with F-numbers as low as 1.
The Clear Align INSPIRE(TM) is a series of pre-engineered, high-performance, SWIR lenses with F-numbers as low as 1.