Multi-Dimensional Shift Multiplexing Technique with Spherical Reference Waves

Abstract

Holographic data storage (HDS) is a next-generation optical storage that uses the principles of holography. The multiplex holographic recording method is an important factor that affects the recording capacity of this storage. Various multiplex recording methods have been proposed so far. In this study, we focus on shift multiplexing with spherical waves and propose a method of shift multiplex recording that combines the in-plane direction and thickness direction of the recording medium. In conventional shift multiplexing with spherical waves, shift multiplexing is usually carried out with respect to the direction parallel to the plane of the recording medium. By focusing on the fact that shift selectivity is also in the thickness direction, we examined the possibility of a multiplex recording method that combines multiple shift directions. Simulation and experimental verification shows that the proposed method is effective in principle.