2. 21/30/2015
Holographic memory is a technology
that can store information at high
density inside crystals or
photopolymers.
The advantage of this type of data
storage is that the volume of the
recording media is used instead of
just the surface .
3. 31/30/2015
Technical aspects
Like other media, holographic media
is divided into write once and
rewritable media .
Rewritable holographic storage can
be achieved via the photorefractive
effect in crystals
4. 41/30/2015
Mutually coherent
light from two
sources creates an
interference pattern
in the media. These
two sources are
called the reference
beam and the signal
beam
5. 51/30/2015
To record on the hologram, the data in
the form of electric signal is converted
to optical signals by a page composer
The controller generates the address to
access the desired page
This results in the exposure of a small
area of the recording medium through an
aperture
6. 61/30/2015
The optical output signal is directed to
the exposed area by the deflector
Using this beam deflecting mechanism,
the light (which carries the information)
and the reference beam are made to
interact
7. 71/30/2015
The interference pattern is thus recorded
on the hologram. To record a different
page, the aperture is moved and the
above process is repeated.
8. 81/30/2015
To retrieve the information stored in a
hologram, shine the reference beam
directly onto the hologram. When it
reflects off the hologram, it holds the
light pattern of the image stored there.
Then send this reconstruction beam to
a CMOS sensor to recreate the original
image.
10. 101/30/2015
ADVANTAGES
HVD offers several advantages over
traditional storage technology. HVDs can
ultimately store more than 2 terabyte
(TB) of information -- that's 400 times
more than a single-sided DVD and 40
times more than a current double-sided
Blu-ray than a single-sided DVD and 20
times more than a current double-sided
Blu-ray DVD
11. 111/30/2015
HVDs also use a thicker recording layer
than DVDs -- an HVD stores information
in almost the entire volume of the disc,
instead of just a single, thin layer.
HVDs storing holograms in overlapping
patterns, while a DVD basically stores
bits of information side-by-side
12. 121/30/2015
The other major boost over conventional
memory systems is HVD's transfer rate
of up to 1 gigabyte (GB) per second --
that's 40 times faster than DVD. An HVD
stores and retrieves an entire page of
data, approximately 60,000 bits of
information, in one pulse of light, while a
DVD stores and retrieves one bit of data
in one pulse of light.
15. 151/30/2015
Development and marketing
At the National Association of
Broadcasters 2005 (NAB) convention in
Las Vegas, conducted the first public
demonstrations of the world’s first
prototype of a commercial storage
device at the Maxell Corporation of
America booth.
16. 161/30/2015
The three main companies involved in
developing holographic memory,
Polaroid spinoff Aprilis, and Optware of
Japan ,IBM