A diffractive optical element has a plurality of diffraction structures
for a certain wavelength. These each have a width measured in the plane
of the diffractive optical element and a height measured perpendicularly
thereto. The widths and the heights of the diffraction structures vary
over the area of the diffractive optical element. An optical arrangement
comprising such a diffractive optical element has, in addition, a neutral
filter. The efficiency of such a diffractive optical element and of such
an arrangement can be optimized locally for usable light.