Abstract

The evolution of the radiation inside the high volume lasers with unstable resonators is quite different compare to the classic Gaussian resonators with standing waves. The spectral structure formed in unstable resonators is not clear. To recognise the spectral frequency components of the output radiation from unstable resonators we built the system for the heterodyne analysis shown in Fig. 1. It enables to detect the self-beat frequencies of modes in the laser output (so called homodyne detection), or heterodyne signals when the tunable single-mode laser is used as a reference to obtain the beat signal (heterodyne detection) [1].

© 1998 IEEE