Varifocal lens

Varifocal lens

A varifocal lens is a camera lens with variable focal length in which focus changes as focal length (and magnification) changes, as compared to "parfocal" ("true") zoom lens, which remains in focus as the lens zooms (focal length and magnification change). Many so-called "zoom" lenses, particularly in the case of fixed lens cameras, are actually "varifocal lenses". [ cite web|url=http://www.rogercavanagh.com/helpinfo/30_parfocal.stm |title=Parfrocal Lenses |accessdate=2007-11-18 |last=Cavanagh |first=Roger |date=2003-05-29 ]

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  • varifocal lens — kintamojo židinio objektyvas statusas T sritis fizika atitikmenys: angl. variable focus objective; variable focus lens; varifocal lens vok. Objektiv mit veränderlicher Brennweite, n; Varioobjektiv, n; Zoom Objektiv, n rus. вариообъектив, m;… …   Fizikos terminų žodynas

  • varifocal lens — noun A spectacle lens whose magnifying power varies from top to bottom, allowing them to be used for both distance use and for reading …   Wiktionary

  • varifocal lens — |verē, |va(a)rē+... noun Etymology: vari + focal : zoom lens …   Useful english dictionary

  • varifocal — [ˌvɛ:rɪ fəʊk(ə)l] adjective denoting a lens that allows an infinite number of focusing distances for near, intermediate, and far vision. noun (varifocals) varifocal glasses …   English new terms dictionary

  • varifocal — adj. & n. adj. having a focal length that can be varied, esp. of a lens that allows an infinite number of focusing distances for near, intermediate, and far vision. n. (in pl.) varifocal spectacles …   Useful english dictionary

  • Zoom lens — Nikkor 28 200 mm zoom lens, extended to 200 mm at left and collapsed to 28 mm focal length at right A zoom lens is a mechanical assembly of lens elements for which the focal length (and thus angle of view) can be varied, as opposed to a fixed… …   Wikipedia

  • zoom lens — noun a camera lens that magnifies the image • Syn: ↑telephoto lens • Hypernyms: ↑camera lens, ↑optical lens * * * noun : a camera lens in which the focal length and the image size can be varied continuously so that the image remains in focus at… …   Useful english dictionary

  • Parfocal lens — A parfocal lens is a lens that stays in focus when magnification/focal length is changed. There is inevitably some amount of focus error, but small enough not to be considered significant.MicroscopyParfocal microscope objectives stay in focus… …   Wikipedia

  • lente varifocal — Eng. Varifocal lens Ver lente progresiva …   Diccionario de oftalmología

  • variable-focus lens — kintamojo židinio objektyvas statusas T sritis fizika atitikmenys: angl. variable focus objective; variable focus lens; varifocal lens vok. Objektiv mit veränderlicher Brennweite, n; Varioobjektiv, n; Zoom Objektiv, n rus. вариообъектив, m;… …   Fizikos terminų žodynas

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