holographic memory
DESCRIPTION
A presentation on the physics and working of Holographic memory and HVDs.TRANSCRIPT
BySayandeb Banerjee
(13000311075)Shiladitya Bandopadhyay
(13000311077)
Siddhartha Chattaraj(13000311082)
Soumya Deep Das(13000311089)
Mentor
Prof. Amiya Kumar Sarkar
Table of Contents
• A Glance at History
•What is a Hologram?
•What is Holographic Memory?
•Working Principle
•HVD
•HVD Disc Structure
• Collinear Holography – Writing Data
• Collinear Holography – Reading Data
•HVD vs. Other Optical Discs
A Glance at History
The Drive for More Memory!1928
Magnetic Tape
1956Hard Disk
1971Floppy Drive
1980CD
1994Flash
1995DVD
2003Bluray
HVD
LASER
OBJECT
BEAM SPLITTER
MIRROR
PHOTOGRAPHIC PLA
TEDIFFUSION LENSES
Refere
nce
beam
Signal beam
“A three-dimensional image formed by the interference of light beams from a laser or other coherent light source.”
• A mass storage technology that uses three-dimensional holographic images to enable more information to be stored in a much smaller space.
• A potential technology in the area of high-capacity data storage currently dominated by magnetic and conventional optical data storage.”
10100110011100010110101010101010101010100101010101001010101000110011010111111011011111010101010010010101101010
Working Principle
SLM
COVER LAYER
RECORDING LAYER
REFLECTIVE LAYER
OBJECTIVE LENS
Deffracted Information
beam (page data)
Deffracted Reference
beam (modulated)
HVD
An optical disc technology developed between April 2004 and mid-2008 that can store up to several terabytes of data on an optical disc 10 cm or 12 cm in diameter.
Prototypes
developed with
up to 3.9Tb
capacit
yData
transf
er
rate
up to
1Gbps
HVD Disc Structure
Gap Layer
PitBase Layer
Aluminium reflective Layer
Dichroic Mirror Layer
Recording Layer(photo polymer)
Cover Layer
Hologram
Red LightGreen or Blue Light
10100110011100010110101010101010101010100101010101001010
Data
Data Pages
SLM
Laser
Recording Medium
Reference Beam
Signal Beam
Relay Optics
Writing Data
Recording Medium
Reference Beam
Relay Optics
ImageOptics
Detector
10100110011100010110101010101010101010100101010101001010
Laser Recovered Data
Reading Data
DVD DVD Blu-ray Blu-ray HVD
Number of Layers Single Dual Single Dual 200 +/-
Recording Capacity 4.7BG 9.4GB 25GB 50GB 3.9TB
Data Transfer Rate 11.08MB/s
11.08MB/s
36MB/s 36MB/s 1GB/s
IBM's test platforms can store up to 390 bits per square micron. DVDs, by contrast, have a storage density of about five bits per square micron.
HVD vs. Other Optical Discs
Storage & Speed
HVD vs. Other Optical DiscsTechnology
Data is burnt 1 bit at a time
Thin surface recording
substrate~1mm
Serial data1bit/pulse
Volumetric recording
Page data is recorded in the volumetric Recording layer
Page data through SLM60,000 bits/pulse
200 – 300bits/ mm
Conventional Optical Disc Holographic Optical Disc
HVD vs. Other Optical Discs
Life Expectancy
HVD’s have an estimated archival life expectancy of at least 50 years or more compared to CD/DVD archival life of 2 to 5 years (even though published life expectancies are often cited as 10 to 25 years or longer for optical media, it depends on the storage conditions and quality of the disks).
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