Complex method for measuring losses and amplification in active and passive ring laser cavities

A complex method for measuring the parameters of laser resonators is considered. A combination of two fundamental methods for measuring the Q factors of resonators, namely, a method based on analysis of the transmission spectra of multiple-beam interferometers and a method for measuring the radiation decay in high-quality resonators, in one measuring device allowed us not only to extend in fact indefinitely the range of parameters being measured but also to obtain a new method for measuring the gain in the active medium in the resonator.