Independent and combined information transfer from axicon and helical phase distributions

Appl Opt. 2014 Jul 20;53(21):4691-9. doi: 10.1364/AO.53.004691.

Abstract

Helical phase distributions used for optical information transfer increase its capacity by offering a characteristic spatial intensity arrangement for the diffracted beam. Here we propose the superposition between helical phase distribution with an axicon type. They form a composed object placed in the object arm to generate holographic masks. The diffracted patterns from these masks exhibit asymmetric shapes and peaks along the optical axis, with two kinds of spots, which contain independent or combined information from both phase distribution constructive parameters. To read these parameters based only on the diffraction patterns analysis, we generate the match reading masks (RMs) to be inserted in the optical path. In this proof-of-concept experiment, we demonstrate that one can sort constructive parameter values of each phase distribution, from both kinds of spots, using specific RMs.