Data stored as volume holograms--optical interference patterns imprinted into a photosensitive storage material--can be accessed both by address and by content. An optical correlation-based search compares each input query against all stored records simultaneously, a massively parallel but inherently noisy analog process. With data encoding and signal postprocessing we demonstrate a holographic...

The information age has brought with it an everincreasing demand for storage systems that have high capacity, fast data-transfer rate, and short access time. Vast memory systems are required for supporting the many storage-intensive computer applications such as multimedia, video on demand, and network-based computing. Optical memories already play an important role in existing commercial syste...

Semiconductor lasers are commonly used for storage and retrieval of information in optical data recording systems. A measure of the importance of this emerging optoelectronic technology is provided by the compact-disc players that have already penetrated the consumer electronics market. The same technique is now being extended to the mass storage devices capable of storing gigabytes of informat...

Holographic storage has the potential to become a digital data storage technology with fast readout and high density. Computer users have come to expect, however, that data retrieved from their storage devices will be retrieved error-free (with a probability of error <10−12). In both conventional storage devices and holographic data storage, achieving this degree of reliability involves a good ...

There are available today many data storage devices that serve the diverse application requirements of the consumer, professional entertainment, and computer data processing industries. Storage technologies include semiconductors, several varieties of optical disk, optical tape, magnetic disk, and many varieties of magnetic tape. In some cases, devices are developed with specific characteristic...

Multi-wavelength and multilevel (MWML) optical storage with photochromic media is a novel technology that can increase storage capacity and transfer rates significantly. Signal processing and coding methods for the MWML storage channel are introduced in this paper. Two-dimensional codes with parallel detection and equalization are studied to increase storage capacity and combat the crosstalk be...

Current performance in two-photon volumetric data storage is presented and future directions discussed. Influence of numerical aperture in a 3-D multi-layer optical data storage system is analyzed.