relative aperture


relative aperture
noun
: a measure of the angle of the cone of light rays from an object that traverse an optical system; specifically : the effective aperture of a camera lens expressed as a fraction of its focal length with the symbol f being used instead of 1 as the numerator or expressed as the ratio of the effective aperture to the focal length

a lens having an effective aperture that is 1/45 of its focal length has a relative aperture of f/4.5 or 1:4.5

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Optics.
the ratio of the diameter of a lens, esp. a camera lens, to the focal length; the reciprocal of the f number or focal ratio of the lens.

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relative aperture noun
(in a camera) the ratio of the diameter of the lens to the focal length usu expressed as the f-number
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Main Entry:relate

Useful english dictionary. 2012.

Look at other dictionaries:

  • relative aperture — Optics. the ratio of the diameter of a lens, esp. a camera lens, to the focal length; the reciprocal of the f number or focal ratio of the lens. * * * ▪ optics       the measure of the light gathering power of an optical system. It is expressed… …   Universalium

  • relative aperture — santykinė apertūra statusas T sritis fizika atitikmenys: angl. aperture ratio; relative aperture vok. Öffnungsverhältnis, n; relative Apertur, f rus. относительная апертура, f pranc. ouverture relative, f …   Fizikos terminų žodynas

  • Lens [object(ive) glass, relative] aperture — Относительное отверстие объектива …   Краткий толковый словарь по полиграфии

  • aperture ratio — santykinė apertūra statusas T sritis fizika atitikmenys: angl. aperture ratio; relative aperture vok. Öffnungsverhältnis, n; relative Apertur, f rus. относительная апертура, f pranc. ouverture relative, f …   Fizikos terminų žodynas

  • aperture — apertural /ap euhr choor euhl/, adj. apertured, adj. /ap euhr cheuhr/, n. 1. an opening, as a hole, slit, crack, gap, etc. 2. Also called aperture stop. Optics. an opening, usually circular, that limits the quantity of light that can enter an… …   Universalium

  • relative Apertur — santykinė apertūra statusas T sritis fizika atitikmenys: angl. aperture ratio; relative aperture vok. Öffnungsverhältnis, n; relative Apertur, f rus. относительная апертура, f pranc. ouverture relative, f …   Fizikos terminų žodynas

  • aperture ratio — noun : relative aperture * * * Optics. See relative aperture. [1885 90] …   Useful english dictionary

  • aperture ratio — Optics. See relative aperture. [1885 90] * * * …   Universalium

  • Aperture — For other uses, see Aperture (disambiguation). f stops demonstrated on a lens …   Wikipedia

  • ouverture relative — santykinė apertūra statusas T sritis fizika atitikmenys: angl. aperture ratio; relative aperture vok. Öffnungsverhältnis, n; relative Apertur, f rus. относительная апертура, f pranc. ouverture relative, f …   Fizikos terminų žodynas