2. Contents
2
Introduction to Holographic Memory
Components of Holographic Memory
Basics of working
Writing to disk
Reading from disk
Spatial Light Modulator
Storing techniques
Properties of Holographic Data Storage
Applications of Holographic Memory
Pros and Corns of the system
Conclusion
References
3. Introduction to Holographic
Memory
Holographic memory is a developing technology that has promised to
revolutionize the storage systems.
Holographic memory is an advanced optical storage device that can
store information in the form of holographic image.
A method of producing a three-dimensional image of an object by
recording on a photographic plate or film the pattern of interference
formed by a split laser beam and then illuminating the pattern either
with a laser or with ordinary light.
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4. 4
HVD technology
1. Green writing/reading laser
(532 nm)
2. Red positioning/addressing
laser (650 nm)
3. Hologram (data)
4. Polycarbon layer
5. Photo polymeric layer (data-
containing layer)
6. Distance layers
7. Dichroic layer (reflecting
green light)
8. Aluminum reflective layer
(reflecting red light)
9. Transparent base
5. 5
Cont..
• Holographic Versatile Disc(HVD) is an optical disk
technology still in research stage which would hold up to
3.9 TB of information
• The HVD also has a transfer rate of 1 gigabyte/s
• It is a technique that can store information inside crystals
or photopolymers.
6. Components of Holographic Memory
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1. Blue-green Argon Laser
2. Beam splitters to spilt the laser beam
3. Mirrors to direct the laser beams
4. LCD panel (spatial light modulator)
5. Lenses to focus the laser beams
6. Lithium-niobate crystal or photopolymer
7. Charge coupled device camera
8. 8
working principle
SLM
Objective Lens
Cover Layer
Recording Layer
Reflective Layer
Inner :Information
Outer :Reference
Fourier transformed
information beam
Diffracted reference
beam (modulated)
Diffracted information
beam (page data)
Fourier transformed
reference beam
Recorded Hologram
9. A Spatial Light Modulator is used for creating binary information out
of laser light. The SLM is a 2D plane, consisting of pixels which can be
turned on and off to create binary 1’s and 0’s.
An SLM can usually be refreshed at rates of about 1000 frames per second
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SLM
11. 11
Cont..
Wavelength Multiplexing : Alters the wavelength of source
and reference beams between recordings
Spatial Multiplexing : Changing the point of entry of source
and reference beams into the recording medium
16. 16
Data Transfer Rate
1985 1990 1995 2000 2005 2010 2015
Availability Year
1M
10M
100M
1G
10G
100G
DataTransferRate,bits/sec
Blu-ray HD
DVD
0.1M
DVD
Tape
HDD
17. How HVD compares with other storage
device?
• While HVD is attempting to revolutionize data storage, other discs are
trying to improve upon current systems. Two such discs are Blu-ray
and HD-DVD, deemed the next-generation of digital storage.
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HD-DVD Blu-ray HVD
Initial cost for
recordable disc
Approx. $10 Approx. $18 Approx. $120
Initial storage
capacity
30 GB 54 GB 300 GB
18. 18
Applications of Holographic Memory
• Data Mining : Retrieval of data is very fast and storing
large amount of data in a single disk.
• Petaflop computation : performs thousand trillion
floating point operations per second.
• Holographic memory can be used as an extended
DRAM with 10ns access time.
19. 19
Advantages of Holographic Memory
1. Resistance to damage - If some parts of the medium are damaged,
all information can still be obtained from other parts.
2. Efficient retrieval - All information can be retrieved from any part
of the medium.
3. High storage capacity of 3.9 terabyte(TB)
4. While reading data the entire page of data can be retrieved quickly
and at one time .
5. Backward compatible, supports CD’s and DVD’s also.
20. 20
Disadvantages of
Holographic Memory
• Manufacturing cost of HDSS is very high.
• There is a lack of availability of resources which are needed
to produce HDSS.
• Writes in the same fashion can degrade
previous writes in the same region of the medium.
21. 21
Cont..
• The re-illuminated reference beam used to retrieve the
recorded information, also excites the donor electrons and
disturbs the equilibrium of the space charge field in a manner
that produces a gradual erasure of the recording.
• The crystal used as the photographic filament must have
exact optical characteristics.
22. 22
Holographic Memory Systems
Fuji Photo Film
Imation
Toshiba
Konica-Minolta
Matsushita/Panasonic
Memory-Tech
Micron
Mitsubishi Chemical
Nippon Paint
OPTWARE
TV Asahi Corporation
TV Tokyo Corporation
Warner Bros.
Disney
Universal
Pioneer
Sanyo
JVC
NEC
InPhase Technologies
Maxell
Aprilis
SOME OF THE CURRENT PLAYERS
23. Conclusion
HVD will soon replace present DVDs.
It is currently supported by more than 170 of the world's
leading consumer electronics, personal computer,
recording media, video game and music companies.
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