For more than five decades, magnetized media and optical has been the
convention. That won’t necessarily be the case going forward,
especially once holographic storage becomes available.
When you think data storage, you would typically imagine magnetic and
optical hard drives. Sure, these hard drives have become much smaller
since they were first introduced (in the 1950s), but the same mechanism
remains. Data storage has always involved a rotating disc with a
magnetized cover material, or lasers doing the recording.
What is holographic storage?
Holographic storage is an exciting potential technology seen to be a
game changer in high capacity data storage. The technology makes use of
photosensitive media and laser beams so that you could store holograms
or 3D images that are actually data.
The promise of these solutions has been bantered about for years, but
it seems to be poised to hit the market in a real capacity this decade.
InPhase Technologies,
a pioneer in holographic data storage technology, explains that the
main difference between holographic storage and conventional storage is
that holography makes use of the full depth of the medium it is
recording on. With magnetic storage, only the surface is used.
Holography also allows you to record data faster because you can
transfer a million bits at a time, in contrast to only one data bit at a
time for the older storage systems.
Holographic storage also allows you to store more data in a smaller
space. This is because you can use different angles of light to store
multiple bits of data in the same area. This saves a lot of space!
Storing and reading data on Holographic Storage
How does holographic storage record information? It basically makes
use of a storage medium, which is light sensitive (like the films you
use for those old instamatic cameras and SLRs), and laser beams.
A single laser beam is split into the signal beam and the reference beam. The signal beam carries the data.
A spatial light modulator is used to encode the data for the signal
beam. The spatial light modulator will convert electronic data into a
series of zeros and ones and then arrange it into a pattern of dark and
light pixels (representing zeros and ones). These patterns are then
arranged into an array consisting of more than a million bits each.
Data is finally stored on the medium when the signal beam and the reference beam intersect.
The “hologram” is created here by the 3D refraction pattern that is etched in the media.
This process is the reason why you could reuse a single area to store
different images. You can use different angles for the reference beam
or you can tilt the media and it will still store your data correctly.
When you need to access the stored data, the reference beam will
reconstruct the hologram, which will be sent to a detector that will
read the data.
Benefits of holographic data storage
Stable and reliable. Holographic data storage allows you to
keep your data stored safely for up to 50 years, something that both
magnetic and optical discs and tapes cannot quite promise. Media used
in holographic data storage are somewhat more impervious to the
elements. It may gather dust, get wet or even get heated and it will
still be usable. It is also difficult to physically tamper with and you
can be sure that it is safe from magnetic fields.
Also, holographic storage works by shining light onto the media,
instead of the driver reading or touching the storage medium, making it
nearly impossible to wear out the holographic media like you would
magnetic tapes.
Portable. Because you can store vast amounts of data using
holographic storage, you will be able to distribute dense data that may
not be feasibly sent over the network otherwise. According to
Emily Price at Mashable, a holographic storage disk can store around four gigabits of data in a cubic millimeter, so just imagine how much data you could lug around!
Fast. Holographic storage allows processing of millions of
bits of data in parallel. Unlike traditional data storage, where you
need to work with one bit of data at a time and in a linear fashion,
holographic storage should prove to be a much faster way to store and
retrieve data.
Challenges of holographic data storage…
Because holographic storage is an upcoming technology, will likely be
cost prohibitive compared to traditional storage options, especially
right out of the gate. Also, capacity might be limited.
In 2012, hVault
announced
that it would soon be shipping holographic disk drives. The first of
these discs will only contain up to 500 gigabytes of capacity. hVault’s
cheapest autoloader will have space for 15 discs and is expected to
retail around $50,000.
Of course, holographic storage is expected to get cheaper and better over time.
Any storage system ever introduced has gone through the pains of
product immaturity at launch. For example, it was intially easy to ruin
a CD-R when the technology was first launched. It took a while before
burn-proof and multi-session techniques were added to ensure that you
could have less recording fails.
The future of holographic data storage
It’s not surprising for holographic storage to be impressive on
paper. While the term actually brings to mind that iconic Star Wars
scene with Princess Leia (“Help me Obi Wan Kanobi!”), all you really get
in real life is a disc. However, it would be interesting to see
whether holographic storage lives up to its promise: longer life span,
durable storage and faster storage times. It would also be interesting
to see whether the storage industry and the general public would embrace
this new technology because that will dictate just how fast performance
and capacity improvements will take hold.
Computer Weekly
states
that hybrid holographic storage media may be introduced to address the
lack of re-writability it suffers from now. Meaning, the new
holographic media might have some Flash memory in it so that people can
rewrite on it.
There are also other obstacles that we would like to see fixed. For
example, on paper, holographic storage should be able to transfer data
at a rate of one gigabit per second. But that doesn’t happen now
because to be able to do that, it would have to use better lasers and
better material for the medium. Manufacturers are making do with the
materials and lasers that are currently available, which is the reason
why holographic data storage is not achieving its potential speed.
Will this be the future of storage? It’s too early to tell, but
Holographic Data Storage certainly has the potential to change the game.
–
Editor’s note: As a business focused on used data storage hardware,
servers and networking, you would think we would be focused on existing
and past technologies. That’s true, but we also love to gaze into the
future, so we thank Michael for taking us there with this piece.