An imaging arrangement and method for extended the depth of focus are
provided. The imaging arrangement comprises an imaging lens having a
certain affective aperture, and an optical element associated with said
imaging lens. The optical element is configured as a phase-affecting,
non-diffractive optical element defining a spatially low frequency phase
transition. The optical element and the imaging lens define a
predetermined pattern formed by spaced-apart substantially optically
transparent features of different optical properties. Position of at
least one phase transition region of the optical element within the
imaging lens plane is determined by at least a dimension of said
affective aperture.