Iterative discrete on-axis encoding of computer generated holograms optimized for generation of large spot arrays

Abstract

The iterative discrete on-axis (IDO) method1 is a computer generated hologram (CGH) encoding algorithm that employs iterative optimization routines such as simulated annealing. The IDO method has been used for the optimization of large 2-D even numbered, spot arrays for optical interconnect applications. Even numbered spot arrays have several performance advantages including low sensitivity to fabrication errors, and reduced computational complexity. Binary and multiple phase level CGHs have been designed and fabricated. Intensity and/or phase of the individual output pixels can be controlled. Methods to decrease the computation time, similar to the recursive mean squares error function described in Ref. 2, have been developed for this use. Diffraction efficiencies of up to 84% have been achieved for generating spot arrays with 100–1024 points.