A simple expression for determining the time response limitations of Fabry-Pérot etalons as a function of the cavity finesse and cavity length is developed. This expression is confirmed by simulations ofthe interactions of short pulses with etalons, as calculated by frequency analysis, and shows that Fabry-Pérot devices can be used with picosecond or shorter pulses, as long as adequate consideration is given to the etalon bandwidth (as determined by the finesse and effective cavity length). For Gires-Tournois etalons, there are stronger limitations on the maximum finesse and effective cavity length because the device operates only on the phase components of the pulse and can cause more severe distortions than the Fabry-Pérot, in which the primary source of pulse distortion is reflection of the edge frequencies of the pulse.
Charles A. Eldering,
Stephen T. Kowel,
"Etalon time response limitations as calculated from frequency analysis," Optical Engineering 32(3), (1 March 1993). https://doi.org/10.1117/12.61057