NPOI

The CHARA Array is an astronomical optical interferometer operated by The Center for High Angular Resolution Astronomy (CHARA) at Georgia State University. CHARA is the World's highest angular resolution telescope at infrared wavelengths. The array will eventually have six 1-metre diameter telescopes, making it one of the most powerful imaging interferometers in the world. CHARA array - Related pages. Similar imaging interferometers include COAST, NPOI and more recently VLTI/AMB ...

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Later, optical interferometry was used on the Mount Wilson Observatory's reflector telescope in order to measure the diameters of stars. This method was extended to measurements using separated telescopes by Johnson, Betz and Towns (1974) in the infrared and by Labeyrie (1975) in the visible. The red giant star Betelgeuse was among the first to have its diameter determined in this way. In the 1980s the aperture synthesis technique was extended to visible light and infrared astronomy by the Cavendish Astrophysics Group, providing the first ve ...

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Optical interferometry, Optical interferometry - Astronomical optical interferometry, Optical interferometry - For further information see, Optical interferometry - The Michelson-Morley experiment, Optical interferometry - Geodetic standard baseline measurements, Optical interferometry - Holography, Optical interferometry - Inertial navigation

Read more here: » Optical interferometry: Encyclopedia II - Optical interferometry - Astronomical optical interferometry

An interferometer works on the principle that two waves that coincide with the same phase will amplify each other while two waves that have opposite phases will cancel each other out. In the beginning, most interferometers used white light sources (e.g., Young's double slit experiment of 1805). Nowadays researchers often use monochromatic light sources like lasers, and even the wave character of matter can be exploited to build interferometers. One of the first examples of matter interferometers were electron interferometers, later fo ...

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Interferometry, Interferometry - Interferometer, Interferometry - Related lists

Read more here: » Interferometry: Encyclopedia II - Interferometry - Interferometer

A famous use of white light interferometry is the precise measurement of geodetic standard baselines as invented by Yrjö Väisälä. Here, the light path is split in two, and one leg is "folded" between a mirror pair 1 m apart. The other leg bounces once off a mirror 6 m away. Only if the second path is precisely 6 times the first, will fringes be seen. Starting from a standard quartz gauge of 1 m length, it is possible to measure distances up to 864 m by repeated multiplication. Baselines thus established are used to calibrate geodetic distance measurement equipment on, leading to a m ...

See also:

Optical interferometry, Optical interferometry - Astronomical optical interferometry, Optical interferometry - For further information see, Optical interferometry - The Michelson-Morley experiment, Optical interferometry - Geodetic standard baseline measurements, Optical interferometry - Holography, Optical interferometry - Inertial navigation

Read more here: » Optical interferometry: Encyclopedia II - Optical interferometry - Geodetic standard baseline measurements