PROFILE OF RELIEF PHASE GRATINGS USED FOR UNIFORM MULTIPLE-BEAM SPLITTING

We investigate relief holographic diffraction gratings with a continuous profile, which split an incident beam into many diffracted beams with equal intensity. It is shown that any grating groove with much different curvatures at the profile extremes can give a uniform distribution of light energy among the diffracted beams, provided that the relevant contribution to the efficiency of most diffraction orders is determined by the shape of the profile apexes at the profile extremes only.