This document discusses holographic data storage technology. It describes how data is encoded in holograms using a laser beam split into a reference beam and data beam. The data beam passes through a spatial light modulator before interfering with the reference beam to store holographic data. Holographic data can be read by directing a laser at the same angle as the reference beam was during writing. Holographic data storage provides significantly higher storage capacities than DVDs in a smaller space and has a longer lifetime. However, challenges remain in reducing costs and developing compatible recording media.

1. HOLOGRAPHIC DATAHOLOGRAPHIC DATA
STORAGESTORAGE
Presented ByPresented By
Adithya H JoshiAdithya H Joshi Manoj Vasishta S SManoj Vasishta S S
4pm11cs0034pm11cs003 4pm11cs0514pm11cs051
CSE,PESITMCSE,PESITM CSE,PESITMCSE,PESITM
-The Emerging Technology

2. OverviewOverview
• IntroductionIntroduction
• Co-linear HolographyCo-linear Holography
• Holographic Versatile DiskHolographic Versatile Disk
• HVD System: Writing DataHVD System: Writing Data
• HVD System: Reading DataHVD System: Reading Data
• AdvantagesAdvantages
• Major ChallengesMajor Challenges
• ObjectivesObjectives
• ReferencesReferences

3. Introduction:Introduction:
• Technology used to produce 3-D images.Technology used to produce 3-D images.
• Dennis Gabor.Dennis Gabor.
• Provides a larger storage capacity in smallerProvides a larger storage capacity in smaller
space.space.
• Data represented as matrix: 0’s - Light squareData represented as matrix: 0’s - Light square
1’s - Dark square1’s - Dark square
• Data storage device - HVDData storage device - HVD
• Technology used - Co-linear HolographyTechnology used - Co-linear Holography

4. Co-linear Holography:Co-linear Holography:
• Single laser beam is split into two:Single laser beam is split into two:
1.Reference beam1.Reference beam
2.Data beam2.Data beam
• Spatial Light Modulator (SLM) - processesSpatial Light Modulator (SLM) - processes
light and dark squares and sends laser beamlight and dark squares and sends laser beam
to storage medium.to storage medium.

5. Holographic Versatile Disk:Holographic Versatile Disk:
• Optical disk - Only surface layerOptical disk - Only surface layer
HVD - Most of the layers.HVD - Most of the layers.
• 2 lasers - green or blue laser, red laser.2 lasers - green or blue laser, red laser.
• A dichroic mirror layer separates RecordingA dichroic mirror layer separates Recording
layer and address layer.layer and address layer.

6. Writing Data on to HVD:Writing Data on to HVD:
• Encoding of information into binary-data – SLM.Encoding of information into binary-data – SLM.
• 1’s - translucent1’s - translucent
0’s – opaque0’s – opaque
• Information beam passesInformation beam passes
through SLM.through SLM.
• Portion of beam throughPortion of beam through
translucent area interferencingtranslucent area interferencing
with reference beam formswith reference beam forms
holographic data.holographic data.
Page of data

7. Reading data from HVD:Reading data from HVD:
• Retrieving light pattern from hologram.Retrieving light pattern from hologram.
• To read data, Laser angle = Reference beam angle.To read data, Laser angle = Reference beam angle.
• Diffracts the laser beam according to theDiffracts the laser beam according to the
interference pattern stored.interference pattern stored.
• Diffracted beam - ReconstructionDiffracted beam - Reconstruction
beambeam
• Reconstruction beam - RecreatesReconstruction beam - Recreates
page of data in the 1page of data in the 1stst
place asplace as
stored earlier.stored earlier.

8. Advantages:Advantages:
1. Increased storage capacity:1. Increased storage capacity:
• Digital media – increased demands.Digital media – increased demands.
• 200 DVDs = 1 HVD of size 1 TB.200 DVDs = 1 HVD of size 1 TB.
• Future capacity 6 TB (present 3.9 TB).Future capacity 6 TB (present 3.9 TB).
• Storage density: HVD - 390 bit/sq. micronStorage density: HVD - 390 bit/sq. micron
DVD – 5 bit/sq. micronDVD – 5 bit/sq. micron
• All the books in U.S library of congress canAll the books in U.S library of congress can
be stored in 6 HVD’s.be stored in 6 HVD’s.
• The pictures of every landmass on Earth can
be stored on two HVD’s.

9. 2. Increased read/write speed:2. Increased read/write speed:
• Data transfer rate billion bits/second.Data transfer rate billion bits/second.
3. Longer storage life:3. Longer storage life:
• HVD -HVD - 5050 yearsyears
• DVD - 2 to 5 yearsDVD - 2 to 5 years

10. Major challenges:Major challenges:
• Costlier (nearly $16000)Costlier (nearly $16000)
• Integration of SLM is difficult.Integration of SLM is difficult.
• As now not compatible with CD/DVD’s.As now not compatible with CD/DVD’s.
• Lack of suitable recording medium.Lack of suitable recording medium.

11. Objectives:Objectives:
• Develop awareness of current applications ofDevelop awareness of current applications of
holography in computer data storage.holography in computer data storage.
• Present holography as a new and powerfulPresent holography as a new and powerful
solution model to ever increasing multimediasolution model to ever increasing multimedia
storage requirements.storage requirements.
• Review key concepts and terminology.Review key concepts and terminology.
• Generate dynamic perspective of this new andGenerate dynamic perspective of this new and
emerging technology.emerging technology.
• Stimulate interest in exploring and applying thisStimulate interest in exploring and applying this
new technology using multimedia presentationsnew technology using multimedia presentations
and the internet.and the internet.

12. References:References:
[1]A Detailed Text Book Of Engineering Physics by[1]A Detailed Text Book Of Engineering Physics by
Basavaraj BBasavaraj B
[2]http://wiki.answers.com/Q/What[2]http://wiki.answers.com/Q/What
are_the_advantages_and_disadvantages_Of_Dataare_the_advantages_and_disadvantages_Of_Data
Storage_Device#slide=2Storage_Device#slide=2
[3][3]http://electronics.howstuffworks. comhttp://electronics.howstuffworks. com
[4]http://en.wikipedia.org/wiki/Holo[4]http://en.wikipedia.org/wiki/Holo
graphic_data_storagegraphic_data_storage
[5]http://www.opticsinfobase.org/ao/ abstract.cfm?[5]http://www.opticsinfobase.org/ao/ abstract.cfm?
uri=ao-44-13-2575uri=ao-44-13-2575
[6]http://www.projectsourcecode.in/ Thread-[6]http://www.projectsourcecode.in/ Thread-
Holographic-Memory-Seminar-Report-Abstract-Holographic-Memory-Seminar-Report-Abstract-
322322

13. THANK YOUTHANK YOU