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Implementation of a Reference Interferometer for Nanodetection
Published on: April 26, 2014
Fringe-counting technique used to lock a suspended interferometer
Applied Optics
|September 24, 2010
Abstract:
We implement a digital fringe-counting technique to measure in real time the relative mirror displacement of a suspended Michelson interferometer with modulated optical path length for oscillations much larger than the laser wavelength (λ). This provides the proper error signal for a servo mechanism that reduces the relative displacement within λ/2. The implemented technique does not require extra optics or polarizers and thus can be used for interferometric gravitational wave detectors as a starting procedure to get the system locked.
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