Optical Corner Reflectors
In optics, corner reflectors typically consist of three mirrors or reflective prism faces which return an incident light beam in the opposite direction. In surveying, retroreflector prisms are commonly used as targets for long-range electronic distance measurement using a total station.
NASA has put several optical corner reflectors made of quartz, known as the Lunar Laser Ranging Experiment, on the Moon for use in laser time-of-flight measurement to measure the Moon’s orbit more precisely than was possible before.
Arrays of tiny corner reflectors are used in automobile and bicycle tail lights. Microscopic corner reflector structures can be incorporated into reflective paint for increased visibility at night, although retroreflective spherical beads are more common for this purpose.
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Famous quotes containing the words optical and/or corner:
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—For the State of New Hampshire, U.S. public relief program (1935-1943)
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