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refractive index

noun
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Definition of refractive index

: the ratio of the speed of radiation (such as light) in one medium (such as air, glass, or a vacuum) to that in another medium

Examples of refractive index in a Sentence

Recent Examples on the Web For these wavelengths, most materials have a refractive index that is just very slightly less than one. — Chris Lee, Ars Technica, "Gas jets make beautiful lens for light we can’t normally focus," 21 Dec. 2018 Or the refractive indices may have impossible values. — Chris Lee, Ars Technica, "Researchers 3D print a wormhole… for sound waves," 6 Dec. 2018 An electro-optic modulator takes in a microwave signal, which changes the refractive index of a bit of glass. — Chris Lee, Ars Technica, "Careful phasing of a photonic qubit brings light under control," 8 Feb. 2018 Blue light has to work harder to shift the electrons (the refractive index is larger). — Chris Lee, Ars Technica, "Spinning glass ball rejects light from one direction," 27 June 2018 The electrons respond as if the light were redder (the refractive index decreases). — Chris Lee, Ars Technica, "Spinning glass ball rejects light from one direction," 27 June 2018 Instead, the authors look into partly reflective materials that have a high refractive index and low absorption. — John Timmer, Ars Technica, "The material science of building a light sail to take us to Alpha Centauri," 7 May 2018 As light passes through the glass, its frequency is changed by the periodic changes in refractive index. — Chris Lee, Ars Technica, "Careful phasing of a photonic qubit brings light under control," 8 Feb. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'refractive index.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of refractive index

1839, in the meaning defined above

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The first known use of refractive index was in 1839

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Cite this Entry

“Refractive index.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/refractive%20index. Accessed 17 Jan. 2021.

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More Definitions for refractive index

refractive index

noun

Medical Definition of refractive index

: index of refraction

More from Merriam-Webster on refractive index

Britannica.com: Encyclopedia article about refractive index

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