Multilevel recording of complex amplitude data pages in a holographic data storage system using digital holography

Abstract

A holographic data storage system using digital holography is proposed to record and retrieve multilevel complex amplitude data pages. Digital holographic techniques are capable of modulating and detecting complex amplitude distribution using current electronic devices. These techniques allow the development of a simple, compact, and stable holographic storage system that mainly consists of a single phase-only spatial light modulator and an image sensor. As a proof-of-principle experiment, complex amplitude data pages with binary amplitude and four-level phase are recorded and retrieved. Experimental results show the feasibility of the proposed holographic data storage system.

Correlation-Based Multiplexing of Complex Amplitude Data Pages in a Holographic Storage System Using Digital Holographic Techniques

“…The conventional collinear holographic storage system is not capable of modulating and detecting the complex amplitude distribution of a beam. Unlike the conventional collinear holographic storage system, our proposed system can modulate and detect the complex amplitude distribution of a beam [25]. The principle of a correlation-based multiplexing is related to an optical correlator using a volume hologram [34,35].…”

“…Note that in the phase distribution of Figure 7a, the phase values where the amplitude values are less than 0.3 are represented by the black. The detected complex amplitude is decoded as follows [25]. The complex amplitude distribution was divided to 16 × 16 areas that are the same as the number of cells in a single data page.…”

“…Owing to digital holography, the proposed system can modulate and detect the complex amplitude distribution of a signal beam in a common-path setup consists of a single SLM and a single image sensor. In a preliminary experiment, we have verified that complex amplitude data pages can be recorded and retrieved with shift multiplexing [25]. In shift multiplexing, multiple volume holograms are partially overlapped and recorded by shifting a recording medium.…”

“…For the purpose of recording complex amplitude data pages in a simple optical setup, we have proposed a holographic storage system using digital holography [25]. Digital holography is the technology that records and reconstructs a hologram with electric devices and signal processing, unlike analog holography.…”

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.…”