Time-Domain Differential Detection of Phase-Modulated Signals for Phase-Only Holographic Data Storage

摘要

Holographic data storage with phase-modulated signals has great advantages over conventional intensity-based memory. These include the efficient use of material dynamic range and light power in a spatial light modulator. On the other hand, phase-based holographic data storage has a disadvantage, which is the difficulty in distinguishing phase-modulated signals. We propose and demonstrate a new phase-modulated signal detection method with photorefractive two-wave mixing. This method has several advantages such as high energy efficiency, detection of multi valued phase-modulated signals, and alignment-free optics. In this study, we investigate the spatial resolution of the phase-modulated signal detection method and obtain a spatial resolution of 300-500 μm of incident pixels.