data storage devices holography
TRANSCRIPT
DATA STORAGE DEVICES
What Are Data Storage Devices
All device Using for storing data. Recording can be done Mechanically, Magnetically, or Optically
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.
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
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
Holographic Versatile Discs
This Is 40 year old concept. Initially Difficult To MakeBecause 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.
How Data Stores In HVDs
Structure Of HVDs
Structure Of HVDs In Thickness
1. Green writing/reading laser (532 nm)2. Red positioning/addressing laser (650 nm)3. Hologram (data)4. Polycarbon layer5. Photopolymeric layer (data-containing layer)6. Distance layers7. Dichroic layer (reflecting green light)8. Aluminium reflective layer (reflecting red light)9. Transparent baseP. PIT
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
HVDs Writing System
HVDs Reading System
HVDs Comparison
FACTORS Blu-ray HD-DVD HVD
Initial cost for recordable disc
Approx. $18 Approx. $10 Approx. $100
Initial cost for recorder/player
Approx. $2,000 Approx. $2,000 Approx. $3,000
Initial storage capacity 54 GB 30 GB 200 GB
Read/write speed 36.5 Mbps 36.5 Mbps 1 Gbps
HVDs Comparison
Storage Medium Access Time Data Transfer Rate Storage
Capacity
Holographic Memory
2.4 s 10 GB/s 400Mbits/cm sq.
Main Memory (RAM)
10 – 40 ns 5 MB/s 4.0 Mbits/cm sq.
Magnetic Disk 8.3 ms 5 – 20 MB/s 100 Mbits/cm sq.
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
For Listening Us Carefully