achromatic lens

American  

noun

Optics.

1. a system of two or more lenses that is substantially free from chromatic aberration and in which the lenses are made of different substances so that the focal length of the system is the same for two or three wavelengths of light.

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Etymology

Origin of achromatic lens

Probably earlier than 1860–65

Example Sentences

Photographic Query.—Given the diameter and focal length of a simple achromatic lens; at what distance from it must a diaphragm of given diameter be placed to give the best possible image?

From Notes and Queries, Number 235, April 29, 1854 A Medium of Inter-communication for Literary Men, Artists, Antiquaries, Genealogists, etc. by Various

It was this accuracy of convergence of the light which led Dr. Draper to prefer the mirror to the achromatic lens.

From The Atlantic Monthly, Volume 12, No. 69, July, 1863 by Various

A similar argument may be applied to find at what point an achromatic lens becomes sensibly superior to a single one.

From Encyclopaedia Britannica, 11th Edition, Volume 8, Slice 4 "Diameter" to "Dinarchus" by Various

One is painted with the most brilliant hues of Romanticism, and glows with the essence of the Romantic spirit--Aspiration; the other looks at life through an achromatic lens, and is a catalogue of Realities.

From Essays on Russian Novelists by Phelps, William Lyon

The eye-piece consists of a single achromatic lens, whose focal length is about two inches.

From Experimental Determination of the Velocity of Light Made at the U.S. Naval Academy, Annapolis by Michelson, Albert A.