DIFFRACTIVE OPTICS - DESIGN, REALIZATION, AND APPLICATIONS

This paper presents methods for designing and recording optimal comput er-generated diffractive optical elements, The design method is based on an analytic ray-tracing procedure for minimizing aberrations, The r ecording involves computer-generated mask and multiple lithographic pr ocesses in order to form reflective and transmissive multilevel, surfa ce relief-phase, diffractive elements. As a result, the elements can h ave high diffraction efficiencies over a broad range of incidence angl es. Even generalized diffractive elements that operate with highly uni form diffraction efficiency and polychromatic radiation can be designe d and recorded by optimizing the shape and height of the relief gratin gs. To illustrate the effectiveness of the diffractive optical element s, they have been incorporated into a number of applications, involvin g visible as well as infra-red radiation. Some that deal with coordina te transformation beam shaping, and polarization control are briefly r eviewed.