A.M.Zabelin.

The invention can be used at making technological complexes of laser welding and cutting. Substance: in the device there is resonator and mirror with controllable curvature, thus the resonator is fulfilled unstable only in one plane., and in another (orthogonal first) plane it is fulfilled under the plan of stable resonator, while the controllable mirror is fulfilled in such a manner that at action on it with the help of control periodic signal the surface of a mirror receives the cylindrical shape with on time variable curvature. Using of the offered invention, ensures in the impulse - periodic laser persistence of spatial parameters of beam at using only total reflecting optics, that enables to use given device at major levels of beam power.