Abstract

The availability of high power laser diodes leads to new generation of all solid state lasers including new configurations of diode pumping to increase the laser efficiency and extract much higher energy or average power from the amplifying medium. However, high power pumping brings thermal loading which induces stress birefringence and spatial aberrations. These thermal effects corrupt the laser brightness and therefore induce a degradation of the spatial beam profile. There are now many scientific and industrial applications to material processing which require the ability to focus the beam close to the diffraction limit. In order to attain this objective, nonlinear optical phase conjugation brings attractive capabilities: the aberrations are corrected after reflection on the nonlinear mirror and double passing through the aberrating medium. The mirror adapts in real time to any change of the operating conditions of the laser. Since first basic researches published in the early 80’s, this technique is now getting more mature for being used in complete laser systems with reliable performances.

© 2000 IEEE