Stability of the beam quality of 0.98-/spl mu/m InGaAlAs tapered laser oscillators

We have investigated the beam quality and the astigmatism of tapered semiconductor laser oscillators under perturbation conditions to specify under which conditions such devices can be employed for direct applications such as material processing. The observed saturation of the astigmatism is an important indication that when the laser output is focused the resulting spot position will not change significantly with changes in the pump current.