DIFFRACTIVE OPTICAL ELEMENT, METHOD FOR DESIGNING AN EFFICIENCY-ACHROMATIZED DIFFRACTIVE STRUCTURE, AND METHOD FOR PRODUCING AN EFFICIENCY-ACHROMATIZED DIFFRACTIVE ELEMENT

摘要

The invention relates to a diffractive optical element (1) with a spatial variation in the refractive index, wherein a sequence of adjacent sections (3A-3D), which form a diffractive structure (3), is formed by the spatial variation in the refractive index, within which sections the refractive index varies in each case. Over a spectral range extending over at least 300 nm, the diffractive structure (3) has a diffraction efficiency of at least 0.95, averaged over the entire spectral range. The value of the diffraction efficiency of at least 0.95, averaged over the entire spectral range, is realized by a single single-layer diffractive structure (3) with an optimized combination of at least two refractive indices and at least two Abbe numbers within each section (3A-3D) of the sequence of adjacent sections. The refractive index variation can be achieved by means of doping, material mixing, or structuring into sub-wavelength ranges.