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

By comparing the patterns in forward- and back-scattered light, they could estimate each particle's size and its refractive index, which describes how strongly light bends or scatters when it passes through a material.

From Science Daily • Nov. 17, 2025

"Excitons are very sensitive to the charge density in the material, and therefore we can change the refractive index of the material by applying a voltage," says Van de Groep.

From Science Daily • May 30, 2024

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

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

From Textbooks • Aug. 12, 2015

Moreover the refractive index, while high, is never so high as in a diamond and hence the brilliant cannot be so shaped as to secure the amount of total reflection given by a well-made diamond.

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