Geometrical Transformation of Linear Diode-Laser Arrays for Longitudinal Pumpingof Solid-State Lasers

摘要

A 200-stripe linear diode-laser array is geometrically transformed into a two-dimensional, symmetric virtual source with symmetric divergence to end-pump a Nd:YAG laser. The geometrical transformation is performed by two planes of diffractive optical elements separated by a 2.6-cm gap. Discounting optical losses, a TEM00-mode slope efficiency of 56 percent is demonstrated. Methods of increasing the throughput efficiency of the diffractive elements (currently approximately 50 percent per element) re explored. A theoretical model for estimating the maximum useful pump array size in longitudinally pumped rod and fiber lasers shows that this pump geometry is close to optimum. solid-state lasers, binary optics, etendue, longitudinal pumping, microlens arrays, geometrical transformation, diffraction optics, microoptics.