Currently
the conventional magnetic and optical data storage dominates the field of high
– capacity data storage. But another technology called the holographic data
storage holds the potential to lead this area. Now what is this technology? We
shall discuss about it in this article.
Difference between Conventional storage methods and Holographic Data Storage
- The conventional methods such as the
optical storage and magnetic storage technologies depend up on the recording of
the individual data bits on the distinct optical and magnetic on the medium’s
surface.
- In the holographic technology, the information is
recorded throughout the medium’s volume.
- Multiple images can be recorded
in the same medium area via utilization of the light at varying angles.
- Further, in the conventional storage methods the recording takes place in a linear
fashion whereas,
- In holographic storage, millions of bits can be recorded and
read in parallel thus increasing the rates of the data transfer more than what
are offered by the conventional methods.
Features of Holographic Data Storage
Data Recording:
- The information is stored in a thick photosensitive optical
substance with the help of an optical interference pattern.
- A laser beam is
divided into two un-identical optical patterns (formed of light and dark
pixels) and is projected towards the medium.
- A multitude of holograms in one
volume is recorded by making adjustments in the wavelength, reference beam
angle, media position etc.
Data Reading:
- For reading the stored data,
the same reference beam is reproduced for the creation of the hologram.
- This
light beam is focused up on the photosensitive material that illuminates the
interference pattern which leads to the diffraction of the light.
- The pattern
is then projected to the detector.
- The data is then read in parallel at a rate
more than that of millions.
- This means high data transfer rate.
- It takes less
than 0.2 seconds for accessing the information from a holographic drive.
- Holographic
data storage has offered a solution to many companies for preserving and
archiving the information.
- The WORM (write – once, read many) approach provides
assurance about the content security, risk of modification and overwriting of
the information.
- This technology provides hope for storage of data without
degradation for 50 plus years which is quite more than the current options.
- However, if the same trend is followed, and it becomes possible to store data for 50 –
100 years in same format, that would still be irrelevant.
- This is so because
the format will be changing in less than 10 years.
Types of Holographic Media
- Holographic media is of two types
namely:
- The re-writable media and
- The write once
medium.
- In the former type, the changes can
be reversed but in the latter can the changes are irreversible.
There is no point in the
competition between the holographic storage and the hard drives since the former
can find a market that is based up on the virtues like access speed.
- The
holographic data storage technology does seems to have a future in the video
game market.
In the year of 2009, the GE Global Research did came up with their own demonstration of the holographic
storage medium that could stand the discs that had read mechanisms somewhat
similar to that of the blu–ray disc
players.
