Off axis aberration compensation of focusing with spherical mirrors using deformable mirrors

Summary from only given. The propagation through many optical components, and thermal effects during the amplification processes produce some spatial aberrations onto the beam. The thermal aberrations in the power amplifier (third amplification stage) are very well corrected by cooling the Ti:sapphire crystal down to 120 K where its index remains almost constant. The remaining aberrations will be corrected with a deformable mirror in order to optimise the size of the focal spot and increase the peak intensity. The deformable mirror which is already implemented in our laser chain will also be used to correct the aberrations induced by the focusing spherical mirror. The deformable mirror is silver coated.