Mode coupling in a ruby laser

An analysis is performed for a pulsed ruby laser with a modulator internal to the interferometer resonator. The problem is a transient one, since steady state is not reached during the period of oscillation of the pulsed laser. The solution obtained is not a steady-state solution, but is applicable to the time interval of interest for the ruby laser. It is found that the electric field envelope is composed of frequency components which are multiples of both the modulation frequency and the free-running beat frequency. A comparison is made between the theory and experimental data obtained from loss modulation of a ruby laser.