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Holographic memory for storage of medical data
Every decade or so new data storage technology supersedes current ideas.
Compact discs replaced audiotape, which were then eclipsed by DVDs,
which are now being pushed aside by Blu-ray discs. Researchers at
Toyohashi University of Technology in Japan believe they have come up
with the next big thing – holographic memory – that will take data
storage to the next level for applications including storage of medical
data of patients.
“The era of 3D imaging is just beginning and although today’s 3D TVs are
little more than toys, it is clear that information displayed in 3D is
going to be the way of the future,” says Mitsuteru Inoue, of the
Department of Electrical and Electronic Information Engineering. This
will require huge increases both in data storage capacity and in data
Whereas a Blu-ray disc can store 50 gigabytes of data, tomorrow’s discs
will be required to store 1 terabyte or more to cope with the demands of
3D imaging. Inoue is convinced that the technology to make this possible
Simply put, holography uses light scattered from an object to record and
reconstruct the object for viewing in three dimensions. Inoue and his
team have developed a collinear phase-lock holographic memory that uses
the interference caused by two overlapping laser beams – an information
beam and a reference beam – to record holographic data on a disc.
Moreover, the system employs a magnetooptic spatial light modulator that
enables the recording of multi-level ‘pages’ (threedimensional volumes)
of data at the same time, and these can be represented as twodimensional
patterns on a new type of disc made of photo-polymer material also
devised by the researchers.
“So instead of 1-bit sequential recording used in today’s DVD or Blu-ray
technologies, we can instantly record a million bits per page,” says
Inoue. “And because recording pages is performed simultaneously on
multi-levels, the technology is capable of ultra-fast writing speeds of
1 gigabit per second to a disc with a capacity exceeding 1 terabyte –
enough to store 200 movies, for example.”
The technology has already been proven in the lab and Toyohashi Tech has
set up a venture company called Optware to exploit its potential. Now
the researchers are working to perfect data transfer rates and storage
density, and are also working on a data erase technique to make
rewritable discs possible.
Inoue sees the technology being used by entertainment and consumer
electronics industries to replace current disc technologies, and for
news media, business, and industrial archiving. In the area of medicine,
hospitals will be able to store entire medical histories of patients
over their lifetime.
“Hospitals don’t have the space to store such records today, so doctors
are forced to throw out patient data of old MRI, CT and PET images,”
says Inoue. “A holographic based archival system will rectify this
of upload: 15th Nov 2011