Generalized conversion from the phase function to the blazed surface-relief profile of diffractive optical elements

The problem of the relation between the phase function and the thin microrelief profile of diffractive optical elements is considered in detail through the nonparaxial scalar diffraction theory for the case of a curved substrate surface and an astigmatic incident beam. Local-plane-wave expansions are used to calculate a coefficient of proportionality between microrelief height and phase jump as a function of microrelief orientation and of local slope angles of the incident and the output beams. Nonuniform transition heights between 2 pi-phase zones of the microrelief are calculated. Analytical and numerical data are presented for examples of high-numerical-aperture diffractive lenses on plane, spherical, or aspherical substrate surfaces. (C) 1999 Optical Society of America [S0740-3232(99)00405-6].