Abstract: A modular system of optical components comprising a phase plate, a focusing lens, and a beam expander. The optical components are each mounted in a housing, which has a first and second fine thread. The first and second fine threads are formed such that they can be screwed together. The mounted phase plate is set up such that, together with an aspherical focusing lens, arranged downstream in the optical path, it forms a focus beam shaper for transforming light, collimated to the optical axis, with a wavelength and an input beam density distribution having a Gaussian profile into an output beam density distribution with an alternating beam density profile in at least one image plane.

Abstract: A modular system having at least one top-hat beam shaper and at least one beam expander for diffraction-limited changing of the diameter of a beam bundle, collimated to the optical axis, of monochromatic light with the same wavelength. The at least one top-hat beam shaper is set up for transforming light, collimated to the optical axis, with a wavelength and an input beam density distribution having a Gaussian profile into light, collimated to the optical axis, of an output beam density distribution with a top-hat profile with a plateau homogeneity of at most 0.133 and an edge steepness of at least 0.4. The optical components are mounted in a housing, which has a first and second fine thread formed such that they can be screwed together, wherein during the screwing together the optical axes of screwed-together optical components are aligned within the diffraction-limited divergence.