lens

lens
—lensless, adj. —lenslike, adj.
/lenz/, n., pl. lenses, v.
n.
1. a piece of transparent substance, usually glass, having two opposite surfaces either both curved or one curved and one plane, used in an optical device in changing the convergence of light rays, as for magnification, or in correcting defects of vision.
2. a combination of such pieces.
3. some analogous device, as for affecting sound waves, electromagnetic radiation, or streams of electrons.
4. Anat. See crystalline lens.
5. Geol. a body of rock or ore that is thick in the middle and thinner toward the edges, similar in shape to a biconvex lens.
v.t.
6. Motion Pictures. to film (a motion picture).
[1685-95; < NL, special use of L lens a lentil (from its shape); see LENTIL]

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Piece of glass or other transparent substance that is used to form an image of an object by converging or diverging rays of light from the object.

Because of the curvature of its surface, different rays of light are refracted (see refraction) through different angles. A convex lens causes rays to converge on a single point, the focal point. A concave lens causes rays to diverge as though they are coming from a focal point. Both types cause the rays to form a visual image of the object. The image may be real
inverted and photographable or visible on a screen
or it may be virtual
erect and visible only by looking through the lens.

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▪ France
      industrial town, Pas-de-Calais département, Nord-Pas-de-Calais région, northern France, southwest of Lille. It was the chief urban centre of the Pas-de-Calais coal basin. Since the demise of coal mining in the 1980s, a wide range of new industries and services has been developed in Lens. These include companies manufacturing wires and cables, paper, metals, glass, frozen foods, and chemicals, as well as firms specializing in packaging and transport. Lens is also a commercial and administrative centre, and it is the site of a branch of the University of Artois. The town, which was completely destroyed in World War I, was damaged again in World War II. Pop. (1999) town, 36,206; (2004 est.) 35,200.

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Universalium. 2010.

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  • Lens — (l[e^]nz), n.; pl. {Lenses} ( [e^]z). [L. lens a lentil. So named from the resemblance in shape of a double convex lens to the seed of a lentil. Cf. {Lentil}.] (Opt.) A piece of glass, or other transparent substance, ground with two opposite… …   The Collaborative International Dictionary of English

  • LENS — La ville de Lens comptait en 1990 35 278 habitants et celle de Liévin 34 012. Il s’agit en réalité d’un ensemble de communes qui englobent le quart du bassin minier. Sur le site de passage entre la France et les bas pays, dominée par les hauteurs …   Encyclopédie Universelle

  • lens — [lenz] n [Date: 1600 1700; : Latin; Origin: lentil ; because of its shape] 1.) the part of a camera through which the light travels before it reaches the film ▪ a standard 50mm lens 2.) a piece of curved glass or plastic which makes things look… …   Dictionary of contemporary English

  • lens — (n.) 1690s, glass to regulate light rays, from L. lens (gen. lentis) lentil, on analogy of the double convex shape. See LENTIL (Cf. lentil). Of the eye from 1719. In the vernacular of the photographer, anyone crowding to the front of a group,… …   Etymology dictionary

  • lens — [ lenz ] noun count * 1. ) a thin piece of curved glass or plastic that makes things seem smaller, bigger, or clearer: eyeglasses with thick lenses a ) a piece of equipment that is part of a camera: a camera with a telescopic lens 2. ) the part… …   Usage of the words and phrases in modern English

  • Lens —   [lãs], Stadt im Département Pas de Calais, im Kohlenrevier Nordwestfrankreichs, 38 m über dem Meeresspiegel, 35 000 Einwohner; Steinkohlenbergbau, Kokerei, Stahl und Konfektionsindustrie.   Geschichte:   Lens wurde im Ersten Weltkrieg stark… …   Universal-Lexikon

  • LENS — Graece φακῆ, tenuiorum et Philosophorum cibus, Cynicorum praesertim, olim fuit, cuius encomium vide apud Athen. l. 4. c. 18. Sed et edulio eius tantopere in sacris Esavus legitur gavisus, ut iure primogentiurae illud redimere profanus homo non… …   Hofmann J. Lexicon universale

  • lens — [lenz] n. [L, lentil: from the resemblance to the shape of a lentil] 1. a) a piece of glass, or other transparent substance, with two curved surfaces, or one plane and one curved, regularly bringing together or spreading rays of light passing… …   English World dictionary

  • Lens [1] — Lens (lat.), 1) Linse; 2) (L. crystallĭna), Krystalllinse, s.u. Auge …   Pierer's Universal-Lexikon

  • Lens [2] — Lens, s.u. Lenspumpen …   Pierer's Universal-Lexikon

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