Low-divergence pulse YAG laser and its technological applications

A free-oscillation YAG:Nd laser, emitting pulses at a repetition frequency of 100 Hz, was investigated. The replacement of a plane-mirror resonator with a planoconvex configuration reduced the divergence to 8.5' at the 90% average power level at the expense of a reduction in efficiency by a factor of 1.25. Quantitative estimates based on a theoretical analysis were compared with the experimental results. The lowest possible divergence that could be achieved was governed by the birefringence of the active element. The principal technological parameters of the use of this laser in the cutting of semiconductor plates were determined.