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

See Examples For:

refractive index

A key concept behind this discovery is the refractive index, which describes how much a material bends or slows light.

From Science Daily ● Apr. 21, 2026

The resulting patterns show strong optical contrast because of the light-induced refractive index changes, making them easy to detect with optical methods.

From Science Daily ● Apr. 21, 2026

To address this limitation, the team developed a material with a high refractive index and low loss for the infrared region.

From Science Daily ● Mar. 28, 2024

As the hydrogel heated up and the lenses contracted, they actually expelled some of their water -- upping their density, modifying their refractive index and, ultimately, blurring the image of the N.

From Science Daily ● Oct. 23, 2023

The position and angles of their faces, and cleavages, the absence of bi-refringence, and their high refractive index all showed that the crystals were true diamond.

From Encyclopaedia Britannica, 11th Edition, Volume 11, Slice 5 "Gassendi, Pierre" to "Geocentric" by Various