Optical arrangement, optical grating and method for the manufacture of such an optical grating

摘要

An optical grating has a multiplicity of parallel diffraction structures, which are arranged on a support defining a base face. Each structure has a blaze flank that is inclined substantially at the Littrow angle with respect to the base face, and a back flank. Both flanks together form a reflection layer which comprises a reflective base layer and a transparent protective layer that is connected to the base layer and covers it. The protective layer on the blaze flank and the protective layer on the back flank are made of the same material. The thicknesses of the protective layers on the blaze flank and on the back flank, however, are different.