1. An imaging arrangement comprising: an imaging lens having a certain affective aperture, and an optical element associated with said imaging lens and configured to provide an extended depth of focus of the imaging arrangement, said optical element being configured as a phase-affecting, non-diffractive optical element defining a spatially low frequency phase transition, said optical element together with the imaging lens defining a predetermined pattern formed by spaced-apart optically transparent features of different optical properties, position of at least one phase transition region of the optical element within the imaging lens plane being determined by at least a dimension of said affective aperture.