Refractive Index

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Refractive Index (of a medium)

Ratio of the velocity of light in vacuum to the velocity of light in the medium.

Symbol: n

Note: This index is equal to the ratio of the sines of the angles of incidence (?1) and refraction (?2) when a ray crosses the surface separating vacuum and medium.

Reference: C.I.E. (modified)

Please note that this is the term as it stands in the original IALA Dictionary edition (1970-1989)

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