Blazed Holographic Gratings

Different techniques for blazing holographic diffraction gratings are compared. Sinusoidal, Sheridon and Fourier blaze are treated. The blaze-wavelength-groove-density combinations possible for each of these different methods are presented as regions in the wavelength-groove-density plane. The superiority of Fourier blaze, as long as more than two orders propagate, is demonstrated. The technique for making Fourier blazed gratings is explained in detail. Theoretical and measured efficiency curves for Fourier blazed gratings are presented and compared to efficiency curves of ruled echelette and sinusoidal gratings.