By combining an elliptical-shaped diode laser pump spot with the one-dimensional heat flow in a laser slab, the thermal lens can be shaped to compensate for astigmatism. The intrinsic astigmatism in a Brewster slab was compensated for in two different laser crystals---Nd:YAG and Nd:GdVO4---using this thermal lens-shaping technique. The modeling of the lens allowed the estimation of the thermo-optic coefficient of Nd:GdVO4, and it was found to be 4 (+/-1) x 10-6/K. |