The Effects of Saturation and Regeneration in Ruby Laser Amplifiers

An analytic expression which relates the input and output energies of a ruby laser amplifier has been derived for the general situation in which both saturation and regeneration are present. The solution also includes all other special cases (e.g., weak signal and/or no regeneration) which have been independently treated in the past. The results obtained from the analysis have been compared with those obtained by numerical integration of the nonlinear partial differential equations governing the amplification process, and the agreement is excellent. The majority of situations encountered in practice fall within the limits of the assumptions made in the analysis.