Means for separately modulating the wavefronts of the two components of a light beam

For separately modulating the wave fronts of two in orthogonal transverse directions of polarization (9, 10) polarized components of an in the direction of an optical axis (7) incident collimated light beam (8) is a first polarization-selective optical element (13) on the optical axis (7) arranged, which selectively modulates the wave fronts of the first component. Behind the first optical element, a second polarization-selective optical element (14) on the optical axis (7) is arranged, which selectively modulates the wave fronts of the second component. The first optical element (13), the second optical element (14) and arranged all optionally therebetween on the optical axis (7) optical elements (23) receive the two components of the light beam (8) as a parallel beam.