ASYMMETRIC RESPONSE PROFILE OF A SCANNING FABRY-PEROT-INTERFEROMETER

The finite scanning speed of a scanning Fabry-Perot interferometer induces asymmetry in the response profile to a monochromatic input beam. The amplitude of this profile is mathematically that of a fixed interferometer subjected to an input beam with suitable frequency scanning, and is related to the complex error function. The extent of the asymmetry thus depends on a single parameter, eta=betat(c)2, where beta is the frequency scanning rate and t(c) is the power decay time of the interferometer. To obtain an asymmetry less than 5% in the profile obtained from scanning a monochromatic beam requires a scanning time as much as 100 times of the decay time of the interferometer. Experimental data are in good agreement with our calculations.