Continuous-level phase-only computer-generated hologram realized by dislocated binary gratings.

It is proposed and experimentally demonstrated that a multilevel or even continuous-level phase-only computergenerated hologram can be realized by use of a binary (two-level) structure. The desired phase shift is invoked by introduction of a lateral dislocation of a high-frequency binary grating within each of the elements that constitute the hologram. An asymmetrically distributed spot array has been generated experimentally, and a uniformity error of 6% and an efficiency of 42% have been measured.