Comparison of Coaxial Holographic Storage Arrangements from the M Number Consumption Point of View

Abstract

There are two known competitive arrangements for reflection-type coaxial holographic storage systems: the optical layout developed by OPTWARE, which is a so-called collinear or ''split-aperture system'', and the ''common-aperture system'' developed by the European consortium named ATHOS. We modeled the reference diffraction noise for both arrangements by the beam propagation method (BPM), and compared the results from the M number (M#) consumption point of view. We suggest the use of reference beam apodization for the split aperture system to reduce the diffraction noise caused by the reference beam at the object area.

Gray Apertures for Holographic Data Storage System

“…A gray aperture can be realized by a liquid crystal display or a binary aperture with a coating near the edge. A similar design was proposed by Karpati et al 2) for coaxial HDS systems, and an optical apodization filter is suggested to reduce the diffraction noise caused by the reference beam in the object area. In this paper we model the aperture as a Fourier-plane filter in the HDS channel, so as to investigate the effects induced by the aperture design.…”