Gratings insensitive to light polarization may be useful in many areas of optical engineering, particularly in light demultiplexing application. We study different kinds of binary gratings able to present reflected efficiencies higher than 98% in the –1st order. These are metallic gratings, dielectric gratings deposited on a metallic substrate, total internal reflection gratings and gratings lying on a dielectric multilayer. We study each configuration with respect to manufacturing constraints and optical performances to conclude by providing the most suitable design.