On using a supporting quadric method to design diffractive optical elements

Application of a modified supporting quadric method in diffractive optical element design is described. As an example, we compute the eikonal function to focus into a calculator's image represented by a set of points. Properties of the produced image are analyzed using the scalar diffraction theory. It is shown that the proposed method can be used for the design of diffractive optical elements focusing into a continuous required illuminance distribution. Numerical examples also show that the computed eikonal function is a good initial estimate for the iterative Gerchberg-Saxton algorithm.