A method of performing coherent transformations of optical fields includes forming a far field distribution of the input optical field. A fraction of the formed far field is diffracted by producing localized discontinuities within said far field. A Fraunhofer diffraction pattern of the diffracted optical field is formed. The Fraunhofer diffraction pattern is modified by producing localized optical path differences within the Fraunhofer diffraction pattern. The transformed output optical field is produced in the far field with respect to the modified Fraunhofer diffraction pattern.