Measurements of length, reference frame . ( Unlike many other measurements without a known, absolute minimum, speed has a known maximum and can be measured from a purely relative scale . ) Absolute scales can be used for measuring a variety of things, from the flatness of an optical flat to neuroscientific tests.
22.
Some of his installations are part of permanent collections of museums, for example " Camera lucida " ( 2004 ) and " Toposcan / Ireland 2013 " at the Tokyo Metropolitan Museum of Photography and " optical flat / fiber optic type " ( 2000 ) at the National Museum of Art in Osaka.
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Description : The heart of the Fabry P�rot interferometer are a pair of partially silvered glass optical flats spaced several millimeters to centimeters apart with the silvered surfaces facing each other . ( Alternatively, a Fabry P�rot " etalon " is made of a transparent plate with two reflecting surfaces . ) The flats are often made in a wedge shape to prevent the rear surfaces from producing interference fringes and / or the rear surfaces will be given an anti-reflective coating.
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The heart of the Fabry P�rot interferometer is a pair of partially silvered glass optical flats spaced several millimeters to centimeters apart with the silvered surfaces facing each other . ( Alternatively, a Fabry P�rot " etalon " uses a transparent plate with two parallel reflecting surfaces . ) In Fig . 6, the low-finesse image corresponds to a reflectivity of 0.04 ( " i . e . " unsilvered surfaces ) " versus " a reflectivity of 0.95 for the high-finesse image.