refractive index

American  

noun

Optics.

1. index of refraction.

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refractive index British  

noun

1.  ν.   μ.  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

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Etymology

Origin of refractive index

First recorded in 1830–40

Example Sentences

To tackle this challenge, researchers are actively exploring nanocomposites, integrating nanoparticles into the resin to boost its refractive index.

From Science Daily • May 9, 2024

This arrangement gave each layer a specific, different refractive index, and together the layers kept any light traveling through the fiber from escaping or scattering away.

From Science Daily • Oct. 19, 2023

A refractive index describes how waves propagate in a medium, and is positive in all conventional materials.

From Nature • Jul. 31, 2018

The biggest change in the refractive index, and bending of rays, occurs at the cornea rather than the lens.

From Textbooks • Aug. 12, 2015

Perhaps the surest single method of distinguishing precious stones is to find out the refractive index of the material.

From A Text-Book of Precious Stones for Jewelers and the Gem-Loving Public by Wade, Frank Bertram