US Patent 7903705 Short pulse laser device

A short pulse laser arrangement with, preferably, passive mode-locking, comprising a resonator containing a laser crystal and several mirrors, one of which forms a pump beam coupling-in mirror and one of which forms a laser beam out-coupling mirror, and a multiple reflexion telescope enlarging the resonator length, the resonator in operation having a positive averaged dispersion over a wavelength range concerned; the adjustment of the positive averaged dispersion of the resonator is effected by means of the mirrors of the resonator, at least a few of which are designed as dispersive mirrors.