Analysis of the geometry of a holographic memory setup

Abstract

Typically 4-f systems are considered as the basis for holographic memory setups. However, other geometries, such as the convergent correlator, may also be considered. This is a setup widely used in optical processing architectures but not so much explored in holographic data storage systems. It provides some benefits when used in optical processing such as flexibility in the adjustment between Fourier filter dimensions and the Fourier transform of the scene. It also allows a wider freedom in the choice of the optical systems (lenses) used in the setup since it is no longer necessary that their focal lengths match, and the total length of the setup may be shortened. In this paper we make use of Fourier optics techniques to analyze the validity and possible benefits of this setup in its application to holographic memories. We consider the recording and the reconstruction steps. Both analytical expressions and simulated results are given.