Optical interferometry

Optical interferometry is a technique of interferometry

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combining light from multiple sources in an optical

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instrument in order to make various precise measurements.

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The technique of optical interferometry can make use of white light,

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of monochromatic light (e.g., a sodium lamp) or of

Related Topics:
Monochromatic - Sodium

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coherent monochromatic light (laser light). The main difference between these

Related Topics:
Coherent - Laser

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types of light is their coherence length: for white light, only a few wavelengths, but

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for laser light it can be decimeters or more. In order to see interference fringes at all,

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the optical path lengths travelled by the interfering beams or rays must differ by less than

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their correlation length.

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