parfocal

parfocal
/pahr foh"keuhl/, adj. Optics.
of or pertaining to different eyepieces (of telescopes or microscopes) that all focus their images in the same plane, so that they can be interchanged without readjusting the instrument.
[1885-90; PAR1 + FOCAL]

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Universalium. 2010.

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  • Parfocal — Par*fo cal, a. [Pari + focal.] (Opt.) With the lower focal points all in the same plane; said of sets of eyepieces so mounted that they may be interchanged without varying the focus of the instrument (as a microscope or telescope) with which they …   The Collaborative International Dictionary of English

  • parfocal — Microscope objectives that are mounted in such a way that changing objectives does not put the specimen out of focus are parfocal …   Dictionary of molecular biology

  • 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

  • parfocal — adjective Etymology: Latin par equal + English focal Date: circa 1886 being or having lenses or lens sets (as eyepieces) with the corresponding focal points all in the same plane • parfocality noun • parfocalize transitive verb …   New Collegiate Dictionary

  • parfocal — (par fo kal) A microscope that retains proper focus when the objectives are changed …   Dictionary of microbiology

  • parfocal — adjective Having multiple lenses that have corresponding focal points in the same plane …   Wiktionary

  • parfocal — par·fo·cal ( )pär fō kəl adj having corresponding focal points all in the same plane: having sets of objectives or eyepieces so mounted that they may be interchanged without varying the focus of the instrument (as a microscope) with which they… …   Medical dictionary

  • parfocal — par·focal …   English syllables

  • parfocal — (ˈ)pär+ adjective Etymology: Latin par equal + English focal more at pair : having corresponding focal points all in the same plane : having sets of objectives or eyepieces so mounted that they may be interchanged without varying the focus of the …   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

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