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.

---

Etymology

Origin of achromatic lens

Probably earlier than 1860–65

Example Sentences

For average photography, the camera fitted with Kodak Ball Bearing shutter and tested meniscus achromatic lens is amply efficient, for it will make excellent pictures under ordinary conditions.

From Project Gutenberg

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

From Project Gutenberg

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 Project Gutenberg

If the web of a frog's foot be placed on the stage of a microscope and examined with an achromatic lens, the chromatophores can readily be made out.

From Project Gutenberg

The two spectra do not coincide, and the result, if an achromatic lens be made of these glasses, must be a remnant of color which cannot be neutralized.

From Project Gutenberg