Three-mirror stable resonator for high power and single-mode lasers.

A stable, high Q, three-mirror resonator is proposed for the optimum output coupling and mode control of high power moderate-gain lasers. Theoretical calculations on the beam intensity distributions, spot sizes, and stability conditions are given. Alignment tolerance for a limiting case is discussed. Experimental results with a high power argon-ion plasma tube and a three-mirror stable resonator agree with the theory.