Principle of phase-locking of axisymmetric concentric cavity CO2 laser

Based on the phase-locking principle of Gaussian beam, the phase-locking mechanisms of the spherical wave from axisymmetric concentric cavity (ASCC) CO2 laser are analyzed. And then we study the variety laws of the equiphase surfaces and the light spots of the injected beam. The numerical calculations show that the injected beam could be considered as a spherical wave approximately in the ASCC. The phase-locking of the spherical wave is different from the phase-locking of the Gaussian beam; there are different field distributions between Gaussian beam and spherical wave. And the phase-locking method could improve the maximum value of the light intensity, the encircled energy reflects the degree of phase-locking.