HIGH OPTICAL-TO-OPTICAL EFFICIENCY OF LD PUMPED CW ND-YAG LASER UNDERPUMPING DISTRIBUTION CONTROL

The input and output characteristics of an LD pumped Nd:YAG laser of c w TEM00 operation have been investigated under different pump light di stributions that have been formed by a virtual-point-source pumping sy stem. Compared with a central uniform distribution, a centrally depres sed distribution is found to have a lower thermal lensing effect and a higher optical-to-optical efficiency for operations performed using t he same resonator parameters or within a similar stable range, and the improvement in optical-to-optical efficiency is explained as a result of a reduction in thermally induced aberrations.