1. DATA STORAGE DEVICES

2. What Are Data Storage Devices
 All device Using for storing data. Recording
can be done Mechanically, Magnetically, or
Optically

3. HVD : Holographic Versatile Discs
 Hold 300 Gigabytes Of Data
 10 Times Faster Than A Normal DVD
 Little Wider Than Conventional DVDs
 And Also Slightly Thicker.
 Completely Based on concept of
Holographic-memory
 Developed By InPhase Tech. & Optware
Tech.

4. Basics Of Holographic Memory
 Phenomena of storing information in a
light-sensitive crystal material using the
interference of laser light.
 The recorded patterns of light are called a
hologram.
 Hologram Is Creating By A Focused Beam
– A Laser Light
 This Beam Is Split Into Two Parts
 1) Reference beam
 2) Information beam

5. Basics Of Holographic Memory
Reference Beam Remains Unchanged
Information Beam Passes Through An Image
Then Carries That Image In Its Waveforms
When Both Beams Intersect, It Creates Pattern Of
Light Interference.
Data Stored In Hologram
Holograms Can Theoretically Store Equal To 1
Bit/cubic block The Size Of The Wavelength

6. Holographic Versatile Discs
 This Is 40 year old concept. Initially Difficult To Make
 Because Systems Send Reference Beam & Info.
Beam Into Recording Medium On Diff. axes
 HVDs Can More Than 1 Terabyte (TB).
 Accessed Entire Page At A Time Instead of
Sequentially .
 HVD Stores Info. In Almost The Entire Volume Of
The Disc.
 Stores 60,000 Bits Info. In One Pulse Of Light.

7. How Data Stores In HVDs

8. Structure Of HVDs

9. Structure Of HVDs In Thickness
1. Green writing/reading laser
(532 nm)
2. Red positioning/addressing
laser (650 nm)
3. Hologram (data)
4. Polycarbon layer
5. Photopolymeric layer (data-
containing layer)
6. Distance layers
7. Dichroic layer (reflecting green
light)
8. Aluminium reflective layer
(reflecting red light)
9. Transparent base
P. PIT

10. The HVD System
A simplified HVD system consists of the
following main components:
Blue or green laser
Beam splitter/merger
Mirrors
Spatial light modulator (SLM)
CMOS sensor
Photopolymer recording medium

11. HVDs Writing System

12. HVDs Reading System

13. HVDs Comparison
FACTORS Blu-ray HD-DVD HVD
Initial cost for Approx. $18 Approx. $10 Approx. $100
recordable disc
Initial cost for Approx. $2,000 Approx. $2,000 Approx. $3,000
recorder/player
Initial storage capacity 54 GB 30 GB 200 GB
Read/write speed 36.5 Mbps 36.5 Mbps 1 Gbps

14. HVDs Comparison
Storage Medium Access Time Data Transfer Rate Storage
Capacity
Holographic 2.4 µs 10 GB/s 400Mbits/cm sq.
Memory
Main Memory 10 – 40 ns 5 MB/s 4.0 Mbits/cm sq.
(RAM)
Magnetic Disk 8.3 ms 5 – 20 MB/s 100 Mbits/cm sq.

15. Summary Slide
Different Type Of Data Storage Devices Are:-
Mechanical
 Punch card, Paper Tape
Magnetically
 Recording Tape, Gramophone
Optical
 CDs, DVDs, HD-DVDs
Coming Day Technology
 Blu-Ray Disk (BDs)
Future World Devices
 Holographic Versatile Discs

16. For Listening Us
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