Medium consumption in holographic memories

Abstract

The dynamic range of holographic storage media is traditionally characterized in terms of M/#. However, this is a system parameter that assumes simple, uniform plane-wave holograms. Realistic architectures violate this assumption so that M/# measured with plane waves cannot be used to predict system diffraction efficiency. Thus, there currently is no systematic method predicting signal strength and medium consumption for holographic storage architectures a priori. We define a new material parameter, the modulation integral, M(I), and show how this may be used for dynamic range budgeting and diffraction efficiency prediction in complex storage systems. The method is illustrated by applying it to two architectures, collinear and angle polytopic, in order to estimate the M/# required for achieving a target storage density in the presence of empirical optical scatter noise.

Design concepts for diffusive holographic photopolymers

“…media spatial resolution), and noise caused by optical scatter. Increased Δ n yields monotonic gains in performance, with a scaling that depends on the specific storage architecture . However, this increased Δ n generally also incurs greater penalties in recording‐induced shrinkage and optical scatter, leading to a highly constrained materials design problem in which noise and distortion must be traded off against fast recording and high diffraction efficiency.…”

Analysis of a lens-array modulated coaxial holographic data storage system with considering recording dynamics of material

“…Once the geometry and medium of holographic disc is determined, the M# is determined. Then a very important issue is how to reduce consumption of M# in designing a VHM system [23][24][25]. Although there are studies discussing proper ways to utilize the given M# and enlarge the number of the stored hologram, the optimized condition depends on the detailed design of the VHM system.…”

“…For this architecture, phase spatial light modulator is used to remove the strong peak at the focus [26]. However, the reference beam exposures some regions without signal beam and causes extra M# consumption [23]. Coaxial VHM system uses high-spatial-frequency phase modulation or phase encoded methods to remove the strong peak at the focus [27][28][29][30].…”