Interference fringes from superimposed beams move across a photodetector, creating electrical pulses. Frequency of pulses is direct measure of angular velocity of rotating body. If separation of the sources changes, it affects separation of all fringes equally and does not affect angular velocity measurement.
Interferometer Accurately Measures Rotation Angle
NASA Tech Briefs ; 6 , 1
1982-09-01
Miscellaneous
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English
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