LENS

lens, lense, lens system

(noun) a transparent optical device used to converge or diverge transmitted light and to form images

lens, electron lens

(noun) electronic equipment that uses a magnetic or electric field in order to focus a beam of electrons

lens, crystalline lens, lens of the eye

(noun) biconvex transparent body situated behind the iris in the eye; its role (along with the cornea) is to focus light on the retina

lens

(noun) (metaphor) a channel through which something can be seen or understood; “the writer is the lens through which history can be seen”

Lens, genus Lens

(noun) genus of small erect or climbing herbs with pinnate leaves and small inconspicuous white flowers and small flattened pods: lentils

Source: WordNet® 3.1

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Etymology

Noun

lens (plural lenses or lens)

An object, usually made of glass, that focuses or defocuses the light that passes through it.

A device which focuses or defocuses electron beams.

(geometry) A convex shape bounded by two circular arcs, joined at their endpoints, the corresponding concave shape being a lune.

(biology) A genus of the legume family; its bean.

(anatomy) The transparent crystalline structure in the eye.

(earth science) A body of rock, ice, or water shaped like a convex lens.

(programming) A construct used in statically-typed functional programming languages to access nested data structures.

(by extension, figuratively) A way of looking, literally or figuratively, at something.

lens

(obsolete) plural of lens

Verb

lens (third-person singular simple present lenses, present participle lensing, simple past and past participle lensed)

(transitive, cinematography) To film, shoot.

(geology) To become thinner towards the edges.

Source: Wiktionary

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Lens, n.; pl. Lenses (-êz). Etym: [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.)

Definition: A piece of glass, or other transparent substance, ground with two opposite regular surfaces, either both curved, or one curved and the other plane, and commonly used, either singly or combined, in optical instruments, for changing the direction of rays of light, and thus magnifying objects, or otherwise modifying vision. In practice, the curved surfaces are usually spherical, though rarely cylindrical, or of some other figure. Lenses

Note: Of spherical lenses, there are six varieties, as shown in section in the figures herewith given: viz., a plano-concave; b double-concave; c plano-convex; d double-convex; converging concavo- convex, or converging meniscus; f diverging concavo-convex, or diverging meniscus. Crossed lens (Opt.), a double-convex lens with one radius equal to six times the other.

– Crystalline lens. (Anat.) See Eye.

– Fresnel lens (Opt.), a compound lens formed by placing around a central convex lens rings of glass so curved as to have the same focus; used, especially in lighthouses, for concentrating light in a particular direction; -- so called from the inventor.

– Multiplying lens or glass (Opt.), a lens one side of which is plane and the other convex, but made up of a number of plane faces inclined to one another, each of which presents a separate image of the object viewed through it, so that the object is, as it were, multiplied.

– Polyzonal lens. See Polyzonal.

Source: Webster’s Unabridged Dictionary 1913 Edition

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