“ For Internet applications alone, industry estimates are that storage needs are doubling every 100 days”
-Nelson Diaz, Lucent Technologies
“ Optoelectronics Industry and Technology Development Association projects that by the year 2010, a storage system serving an average LAN will need … 10 TB and a WAN server will require 100 TB to 1 petabyte …of storage”
- Red Herring
Overview of HODS
The Practical Setup
The Green Argon Laser
Laser light is a green 514.5-nm line of an argon-ion laser.
The system is equipped with an argon (514.5-nm) or a krypton (676-nm) laser
Optical power delivered to the apparatus prior to the object/reference beam splitter is as much as 100-400 mW .
What is SLM ?
SLM - Spatial Light Modulator .
SLM consists 1-D or 2-D arrays of light modulating elements.
SLM converts the digital data 1’s or 0’s into a 2-D array of bright & dark spots.
SLM is used to imprint the data on the object beam.
About Lithium Niobate Crystal
Chemical Formula- LiNbO 3 .
It has high photorefractive sensitivity & stability.
It has trigonal structure.
Molecular weight - 147.9.
Band gap - 4eV
What is CCD ?
CCD - Charge Coupled Device .
Its structure was proposed in 1969 by Boyle & Smith.
CCD is a light sensitive device.
CCD converts pixels in images into electric charge.
CCD contains a separate value for each colour.
Storage of one bit of information as a Hologram. a) Superposition of spherical wave from one bit with a coherent plane wave reference beam forming an interference pattern. b) Exposure of a photosensitive medium to the interference pattern. c) Record of the interference grating, stored as changes in the properties of the medium. Storage inside the Photosensitive Medium
Data stream is sent to the SLM as 0’s and
Forms a “checkerboard” pattern
1’s transmit light, 0’s block light
Beam is split
Light passing through SLM is the signal (object) beam
Reflected beam is the reference beam
Beams interfere in the medium to produce hologram much like before
Recording by Figure
Beam no longer split
Reference beam is diffracted off the recorded grating (hologram)
Projected using optic onto CCD
Converts into data stream
Reading by Figure
The everyday user might not notice the impact other than more space on his/her computer.
Big benefactors are big business and internet
Parallel data storage and retrieval allows for very fast data excess for number crunching and experiments (much faster computation times).
Much faster data access for internet servers as well as much larger storage densities.
Cheaper cost per Megabyte once mainstream.
Data storage for libraries, documents and so forth will be cheaper and take up less space and access will be much faster.
Imagine the capability of 6,840 raw uncompressed high quality Video/TV hours, or 2,100,000 chest x-rays, or nearly 10,000,000 high-resolution images, or 30,000 four-drawer filing cabinets of documents or 20,000 DVD'S Worm's or 4,000 BLU-Ray Worm disk's on ONE 10 Terabyte 3.5 in. removable disc.
Long Term !
Eventually HODS’s may take over magnetic and optical devices all together
DVD’s with 10 terabytes on them !
Less need for compression techniques (depending on internet communications)
Even smaller computers (hard drive one of the largest components)
Less power to drive = longer lasting laptops
Current storage memory market exceeds $100 billion dollars worldwide
$47 billion is solely hard disk, $42 billion magnetic tape drives, $6 billion optical disk
This is growing at 40% a year (1998)
HODS has the possibility of taking over this entire market
Can assimilate all these data storage types
Little to no competitive alternatives on the horizon
Who is Involved…
InPhase Technologies , venture of Lucent Technologies
Exclusive purpose is to develop high-performance holographic data storage media
Seem to be leaders in viable product, near useable solution
Government and other participants donate $32 million for research
Large majority of research focused at Standford and IBM ’s Almaden Research Facility
With predicted technology a 1cm 3 laser cube is equal to :
- 6,944,440 1.44MB floppy discs
- 14,286 700 MB CD-ROM’s
40 250 GB hard drives
25 million books of the Library of Congress(US)
Built on technology that’s around for 40+ years
HODS may be the future of data storage
HUGE capacity, Very fast, Smaller
Current storage methods nearing their fundamental limits of storage density