Adrian Hill

Holographic storage of multiple high-capacity digital data pages in thick photopolymer systems.

Multiple digital data pages (480 kbits per page) were holographically recorded and retrieved with low bit-error rates in thick (~250- and ~500-mum) photopolymer media. The photopolymer systems were fabricated with the optical quality and low level of scatter required for digital data storage. We believe that these results represent the first demonstration of holographic storage of high-capacity digital data pages in photopolymer media with the thickness that will be required for such storage densities.

High density, high performance optical data storage via volume holography: Viability at last?

The long held promise of using volume holography to deliver high performance optical storage is reviewed. The problems, which limited the development for many years, are accessed. Finally, we describe a series of innovations, which may make the technology viable at last.

Holographic data storage media for practical systems

Holographic data storage (HDS), which makes use of the full volume of the recording medium, possesses high potential by promising fast transfer rates of hundreds of Megabytes/sec and storage densities greater than 200 Gbytes per 120mm disk. The restrictions that are placed on the holographic media, however, are stringent. Described here is a high performance photopolymer based medium that has the properties necessary to enable this technology. Through the use of several different holographic techniques, the material characteristics that are necessary for holographic storage products may be determined. The two different systems that are discussed here include Plane Wave and Digital Holographic Data Storage. These measured characteristics include high dynamic range (M/#), sensitivity, and small recording-induced Bragg detuning. In addition, results of archival and shelf-life environmental testing of the media will be discussed.

Realization of high-performance holographic data storage: the InPhase Technologies demonstration platform

An overview of the InPhase Technologies holographic demonstration platform is presented. This compact, mobile system is a fully functional holographic recordable drive complete with custom optics and custom control and channel electronics. The development of this device paves the way for the commercialization of this technology.

High-Speed Holographic Data Storage at 500 Gbits/in. 2

A holographic system is presented, along with experimental results that demonstrate data densities of 500 Gbits/in. 2 with a write user rate of 23 Mbytes/sec and a read user rate of 13 Mbytes/sec.

Photopolymer media for holographic storage at ∼ 405 nm

We report new photopolymer media for holographic data storage (HDS) that are photosensitive to laser wavelengths from 400-410 nm. The media possess high dynamic range and photosensitivity, low shrinkage, and good archival and shelf-life stability, which show great promise for a practical HDS system.

Temperature Compensation Strategy for Holographic Storage

A strategy for finding the readout wavelength to compensate for temperature changes in holographic media is presented. Theory and experimental results for a 12 degC change at a data density of 95 Gbit/in2 are demonstrated

Consumer holographic read-only memory reader with mastering and replication technology

What is believed to be a novel holographic design for read-only memory systems allows a compact low-cost consumer drive within a 10 mm drive height, using a lensless phase conjugate readout and a combination of polytopic and angle multiplexing. A two-step mastering method enables production of high-efficiency holographic masters, and fast replication is possible by using only a series of plane-wave illuminations. Mastering and replication techniques are verified experimentally with an array of 125 holograms with no measured bit errors.

Digital holographic data storage in photopolymer systems

We report on the holographic storage and recovery of multiple high capacity (800 X 600, 480 kbit) data pages in 250 micrometer and 500 micrometer thick photopolymer media. The data pages were recovered with raw bit error rates less than 5 X 10-3, the level correctable by current error correction strategies. Our results demonstrate that photopolymer systems can be fabricated with the optical quality and low level of scatter required for digital data storage.

Blue-sensitive rewriteable holographic media

An easily fabricated organic holographic media is presented that is rewriteable, sensitive to 407-nm light, and that exhibits high storage capacity, photosensitivity, and environmental robustness. Data written in this media is nonvolatile to readout with the blue write beam, and is only erased by irradiation with UV light. Over 50 holographic write/erase cycles have been demonstrated to date