Intracavity coherent addition of Gaussian beam distributions using a planar interferometric coupler

We present a compact and practical combined laser resonator configuration in which several Gaussian beam distributions are efficiently combined. It is based on intracavity coherent addition of pairs of Gaussian beam distributions with a planar interferometric coupler. The principle, configuration, and experimental results using pulsed Nd:YAG laser beams are presented. The results reveal more than 92% combining efficiency with a nearly Gaussian output beam, in free running and Q-switched operation.