MURRAY HILL, N.J. - It may be now or never for researchers seeking to prove the viability of holographic data storage for commercial applications. U.S. government funding of research into holographic storage will end early next year, after which private industry will have to foot the bill.
Before the Defense Advanced Research Projects Agency (Darpa) cuts the cord, researchers working in the Holographic Data Storage Systems (HDSS) consortium, a joint venture of government, industry and academia, will demonstrate the technology to interested commercial developers. If none is motivated to pursue commercialization, the research may wither on the vine.
And it would not be the first time: Systems and materials issues stalled development of holographic data storage back in 1976, and the technology remained sidelined until the Defense Department became involved in its development in the mid-1990s.
Now that the government is pulling back, it's uncertain whether industry will pursue the research on its own. Thus far, only Lucent Technologies, in partnership with Imation Corp., has publicly committed to bringing out a prototype. And Lucent and Imation say they plan to re-evaluate the technology's market potential before moving to commercial production.
What has kept companies on the fence, sources said, is that no one has yet proved the technology is manufacturable on a commercial scale. It further faces mounting competition from magnetoresistive technology, which is closing the gap in storage density and transfer rates. Companies like IBM, which has invested millions in holographic data storage but is also committed to magnetoresistive research, may elect for the long term to go with the more-established technology.
Holographic data storage has now reached the critical stage. "All the pieces have come together to enable holographic data storage-electronic components, the integration of systems, and the materials out of the Prism project," said Hans Coufal, co-director of HDSS and a program manager at IBM's Almaden Research Center, based in San Jose, Calif."Now we have to show what fu-ture developments could look like."
The HDSS membership-including IBM, the Rockwell Science Center (Thousand Oaks, Calif.) and Stanford University-is slated to demonstrate its system by April 1. High-density storage will be demonstrated at IBM's Almaden Research Center, high-density storage at high data transfer rates at Stanford, and fast access rates at the Rockwell center.
The sessions will also demonstrate associative retrieval and ways to leverage the pagewise architecture in the way data is stored-features that go beyond data storage, Coufal said, to take advantage of the physics of holography.
The HDSS system used in the demos includes a spatial-light modulator developed by IBM, a data input device for 1-Gbit/second input designed by various partners and a CCD camera from Kodak for 1-Gbit/s data output.
On the materials side, HDSS researchers will work with materials developed by Prism partners Polaroid and others for write-once media, as well as with photopolymers for rewritable media co-developed by Bayer, a German chemical company.
After the demos, researchers will come up with a plan for introducing products into the market. The envisioned niche products include small storage devices with very fast access, priced somewhere between a DRAM and a conventional disk drive; a DVD-like player with higher capacity and data rates; and large libraries with removable storage media.
But it's still uncertain whether the research groups will find any takers for the technology among U.S. companies. "It's not the technical viability of the technology [in question], but the financial viability," Coufal said.
Competition for research dollars is fierce in corporate research departments. IBM, for one, has spent millions to develop holographic data storage component technology and has a holographic data storage system at Almaden. The system is based on technology that uses lithium niobate, a photorefractive material used in early holographic storage systems. The material has since been surpassed by new photopolymers that are more sensitive, to allow faster writing speeds, and are less volatile in terms of temperature and humidity.
Coufal believes it's time for the government to stop funding the research and let companies make a commitment to the technology. He believes corporate funding would be forthcoming if the technology showed "a comparable steep slope of improvement vis--vis magnetic recording."
In recent years, magnetic technology has nearly caught up to holography's storage density and transfer rates.
"In the five years since research has been revived through HDSS and Prism, progress in holographic storage has been phenomenal, and people have achieved what they said they were going to achieve," said Barry H. Schechtman, director of the National Storage Industry Consortium (San Diego). "But at the same time, research in magnetic recording has accelerated."
Schechtman noted that magnetic storage densities advanced faster in the last two years than in the full history of the technology.
"In the 1980s the technology advanced 30 percent per year, in the '90s it increased 60 percent and in the last two years it's advanced at 120 percent per year," he said.
Holographic-storage researchers have two burdens, Schechtman said: "to finish up the proof-of-concept work and demonstrate that all the pieces are there and can work together; and to find an application niche for the technology."
One company believes it can overcome the obstacles holographic storage faces. Lucent Technologies' Bell Laboratories recently committed to funding the commercialization of the technology, together with Imation Corp. The companies agreed to develop a prototype for holographic storage media based on a photopolymer material developed by Bell Labs. If all goes well, Imation will produce write-once commercial media products based on it.
"We believe Lucent has solved the key industry problems [in holographic data storage]," said Brad Rubin, director of R&D at Imation. "The industry has been stopped by materials issues" as it has sought to find suitable photopolymers with the right bit-storage characteristics and sufficient environmental ruggedness in extremes of temperature and humidity.
Imation's charter is to take an experimental substance Lucent has developed for holographic storage media and make it production-worthy at a cost the market can support, Rubin said.
Bell Labs researchers discovered a photopolymer a few years ago that has more sensitivity and better dynamic range than the lithium niobate that had been used for roughly the last 30 years, said Kevin Curtis, group leader for holographic storage at the Physical Research Lab at Bell Labs (Murray Hill). "By adding new techniques, we changed the requirements of the material for write-once, read-many-times [holographic] storage devices," he said.
Curtis predicted that the first-generation holographic drives will be able to store 125 Gbytes of data on a 5-1/4-inch disk with transfer rates of 40 Mbytes/s.