Abstract: In an optically stable laser resonator which includes at one end a fully reflective mirror, a partially reflective mirror serving as an uncoupling window at the other end and a pair of spherical optical mirrors one being diverging and the other being converging to provide an expanded beam at the uncoupling window wherein the beam axis has an incidence angle w.sub.1 with the diverging lens axis which is between 10.degree. and 45.degree. and the axis of the beam extending between the spherical mirrors has an incidence angle with the converging mirror axis which, depending on the mirror distance and the focal length of the mirrors, is so calculated that astigmatism is essentially eliminated.

Abstract: In a method for uniformly removing layers from a coated surface, a laser beam is used for scanning the surface along parallel scanning lines wherein the laser beam has a surface illuminating cross-section with a central area defined between parallel lines extending transverse to the scanning lines and tapered marginal end areas extending from the transverse opposite ends of the central area to a predetermined distance and the scanning line distance is so selected that the central areas of the surface illuminating cross-sections of adjacent scanning lines are spaced by the predetermined distance and the tapered marginal end areas of the beam overlap between the scanning lines and together provide, in the overlap area, for essentially the same laser beam exposure as in the central area.

Abstract: A method of converting the laser radiation of a pump laser into another wavelength range by stimulated Raman scattering in which the laser radiation of the pump laser is conducted through a Raman medium, thus generating Stokes radiation in the other wavelength range, and an arrangement for implementing the method. The laser radiation from the pump laser leaving the Raman medium and the generating Stokes radiation are fed together to an amplifier for the laser radiation of the pump laser, and the thus amplified laser radiation of the pump laser is conducted together with the accompanying Stokes radiation through a further Raman medium for conversion of the amplified laser radiation of the pump laser into Stokes radiation.