Analytical and experimental study of ringing effects in a fabry–perot cavity. Application to the measurement of high finesses

The phenomenon of ringing in swept Fabry–Perot cavities, which leads to discrepancies with respect to usual Airy peaks, exhibits three different regimes, depending on the values of the finesse, the sweep frequency, and the free spectral range of the cavity. In particular, the intermediate case in which the Fabry–Perot cavity transmission essentially oscillates is shown theoretically and experimentally to provide a new simple method to measure the finesse of the cavity. For cavities with intermediate finesses (F ≈ 10 000) this method is experimentally shown to have a precision of the order of 1%.