DESIGN OF DIFFRACTIVE-PHASE AXICON ILLUMINATED BY A GAUSSIAN-PROFILE BEAM

The diffractive-phase axicon can convert the Gaussian-profile beam int o axial uniform intensity distribution with long focal depth and high lateral resolution. Two types of phase-retardation functions for the n onuniform-illuminating axicon are derived in terms of the ray tracing and the geometrical law of energy conservation. Based on the general t heory of the amplitude-phase retrieval in optical system and the itera tion algorithm, the optimization design of the phase distribution of t he diffractive-phase axicon can be achieved. The simulation calculatio ns show that the new approach may successfully offer the design of the desired diffractive-phase axicon with long focal depth and high later al resolution. A comparison of the performances of the holographic axi con with the phase-retardation functions from the geometrical optics p rediction and the diffractive-phase axicon designed by the new approac h is also presented.