Coherence Length

In physics, coherence length is the propagation distance from a coherent source to a point where a wave (e.g. an electromagnetic wave) maintains a specified degree of coherence. Within this distance, the wave in question is most similar to a perfect sinusoidal wave. The significance is that wave interference will be strong within a coherence length of the source, but not beyond it. This concept is also commonly used in telecommunication engineering.

This article focuses on the coherence of classical electromagnetic fields. In quantum mechanics, there is a mathematically analogous concept of the quantum coherence length of a wave function.

Read more about Coherence Length:  Formulas, Lasers

Famous quotes containing the words coherence and/or length:

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    David Hume (1711–1776)

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