refractive index

noun

, Optics.

1. index of refraction.

refractive index

noun

1. physics a measure of the extent to which radiation is refracted on passing through the interface between two media. It is the ratio of the sine of the angle of incidence to the sine of the angle of refraction, which can be shown to be equal to the ratio of the phase speed in the first medium to that in the second. In the case of electromagnetic radiation, esp light, it is usual to give values of the absolute refractive index of a medium, that is for radiation entering the medium from free space νμ

Word History and Origins

Origin of refractive index¹

First recorded in 1830–40

Example Sentences

The effects so produced are the differential results of the change of figure and of refractive index.

From Project Gutenberg

A mounting medium of the highest refractive index, such as realgar, is required to resolve the stri.

From Project Gutenberg

Now the refractive index of Iceland spar is, for the extraordinary ray less, and for the ordinary greater, than for Canada balsam.

From Project Gutenberg

Although the ratio of the sines is constant, the refractive index varies in different media.

From Project Gutenberg

This is to be done by using a film of oil of the same refractive index as the glass.

From Project Gutenberg