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

This effect, known as photorefractivity, occurs when exposure to light alters the refractive index.

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

The key difference in this new approach is the use of molybdenum diselenide, which has a much higher refractive index.

From Science Daily ● Apr. 5, 2026

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 transparency of the cornea is due to the fact that all these structures have the same refractive index.

From Encyclopaedia Britannica, 11th Edition, Volume 10, Slice 1 "Evangelical Church Conference" to "Fairbairn, Sir William" by Various