bifocal lenses

См. также в других словарях:

• bifocal — ► ADJECTIVE ▪ denoting a lens having two parts each with a different focal length, one for distant and one for near vision. ► NOUN (bifocals) ▪ a pair of glasses with bifocal lenses …   English terms dictionary

• bifocal — Having two foci. * * * bi·fo·cal ( )bī fō kəl adj 1) having two focal lengths 2) having one part that corrects for near vision and one for distant vision <a bifocal eyeglass lens> bifocal n 1) a bifocal glass or lens 2) bifocals pl… …   Medical dictionary

• bifocal — I. adjective Etymology: International Scientific Vocabulary Date: 1888 1. having two focal lengths 2. having one part that corrects for near vision and one for distant vision < a bifocal eyeglass lens > II. noun Date: 1899 1 …   New Collegiate Dictionary

• bifocal glasses — glasses with bifocal lenses …   Medical dictionary

• bifocal — adjective denoting a lens having two parts each with a different focal length, one for distant and one for near vision. noun (bifocals) a pair of glasses with bifocal lenses …   English new terms dictionary

• Bifocal — Bi fo cal, a. [Pref. bi + focal.] Having two foci, as some spectacle lenses. [Webster 1913 Suppl.] …   The Collaborative International Dictionary of English

• Линзы Бифокальные (Bifocal Lenses) — очки, в которых верхняя часть стекол позволяет получить четкое изображение удаленных предметов, а нижняя часть стекол позволяет получить четкое изображение предметов вблизи, например, четко видеть текст во время, чтения. См. также Линзы… …   Медицинские термины

• bifocal lens — a lens with two principal focal lengths: the upper part of the lens gives a sharp image of distant objects and the lower part gives a sharp image of near objects, as when reading. Examples are bifocal spectacles, bifocal contact lenses, and… …   Medical dictionary

• bifocal lens — a lens with two principal focal lengths: the upper part of the lens gives a sharp image of distant objects and the lower part gives a sharp image of near objects, as when reading. Examples are bifocal spectacles, bifocal contact lenses, and… …   The new mediacal dictionary

• multifocal lenses — lenses in which the power (see dioptre) of the lower part gradually increases towards the lower edge. There is no dividing line on the lens as there is between the upper and lower segments of bifocal lenses. The wearer can see clearly at any… …   The new mediacal dictionary

• bifocal — /buy foh keuhl, buy foh /, adj. 1. Chiefly Optics. having two foci. 2. (of an eyeglass or contact lens) having two portions, one for near and one for far vision. n. 3. bifocals, bifocal eyeglasses or contact lenses. [1885 90, Amer.; BI 1 + FOCAL] …   Universalium