Radically symmetric hologram and method of fabricating the same

Abstract

A radially symmetric iterative discrete on-axis hologram has a high diffraction efficiency for a correspondingly small f-number. The radially symmetric hologram has a plurality of concentric constant radial phase fringes. Each fringe has a predetermined plurality of radial phase rings and each fringe corresponds to a predetermined plurality of radial phase transition points and a radial phase value between the radial phase transition points. The radially symmetric iterative discrete on-axis hologram also has radial phase fringes with a predetermined number of phase levels, at least two adjacent fringes have a phase level difference which is greater than one and less than the predetermined number minus one. The radially symmetric iterative discrete on-axis hologram is fabricated by determining a plurality of concentric fringes of constant phase with a plurality of radial phase transition points and radial phase values between the radial phase transition points for each concentric fringe. The plurality of radial phase transition points and radial phase values are repeatedly optimized to obtain optimized radial phase transition points and optimized radial phase values which maximize the diffraction efficiency. A radially symmetric hologram with concentric fringes of constant radial phase corresponding to the optimized radial phase transition points and the optimized radial phase values is then fabricated using known fabrication techniques.