Engineering

1. Visveshwaraya Technology University,Belagavi
Government Engineering College,mosalehosahalli
Department of Electronics and communication Engineering
Technical Seminar On
“3D OPTICAL DATA STORAGE”
Under the guidance :
Dr.Baby H T
Head of the department,E&C
GECM,Hassan
Presented by:
Harshitha H C
4HG19EC010

2. C0NTENTS.
 INTRODUCTION.
 OVERVIEW.
 MEDIA DESIGN.
 MEDIA FORM FACTOR.
 MEDIA MANUFACTURING.
 COMMERCIAL DEVELOPMENT.
 BASIC COMPONENT.
 ADVANTAGES AND DISADVANTAGES.
 APPLICATIONS.
 CONCLUSION.
 REFERENCES

3. INTRODUCTION.
 3D optical data storage is the term given to any form of optical
data storage in which information can be recorded and/or read
with three dimensional resolution
 This innovation has the potential to provide byte-level mass
storage on DVD-sized disks.
 Data recording and read back are achieved by focusing lasers
within the medium.
 This technique utilizes a series of microscopic dots or voxels
which are written,read and erased using a laser beam

4. OVERVEIW

5. Four data layers are seen, with the laser currently addressing the
third from top.
The laser passes through the first two layers and only interacts
with third, since here the light is at a high intensity.
Two step coherent image forming process in which a record is
made of interference pattern produced by interaction of waves
diffracted by object
When this is illuminated, the original wave front is reconstructed
Hence we get an image of original diffracted object as a real 3D
dimensional object.

6.  The active part of 3D optical
storage media is usually an
organic polymer either doped
or grafted with the photo
chemically active species.
 Alternatively, crystalline and sol-
gel materials have been used.
MEDIA DESIGN.

7. .MEDIAFORM FACTOR.
Media for 3D optical data storage have been suggested in several
form factors: disk, card and crystal.
 DISC:- allows reading and writing to be carried out by the
familiar spinning disc method.
 CARD:- media is attractive from the point of view of portability ,
but would be of a lower capacity than a disc.
 CRYSTAL,CUBE AND SPHERE:- small solids that store massive
amounts of information

8. MEDIA MANUFACTURING.
 The simplest method of manufacturing – the molding of a disk
in one piece – is a possibility for some systems.
 A more complex method of media manufacturing is for the
media to be constructed layer by layer.
 This is required if the data is to be physically created during
manufacture. However, layer-by-layer construction need not
mean the combining of many layers together.

9. DRIVE DESIGN.
A drive designed to read and write to 3D optical data storage
media may have a lot in common with CD/DVD drives,
However, there are a number of notable differences that must
be taken into account when designing such a drive.
 LASER
 VARIABLE,SPHERICALABERRATION
CORRECTION
 OPTICALSYSTEM.
 DETECTION.
 DATATRACKING.

10. COMMERCIAL DEVELOPMENT.
In addition to the academic research, several companies have been set
up to commercialize 3D optical data storage
 Storex Technologies has been set up to develop 3D media based on
fluorescent photosensitive glasses and glass-ceramic materials
 3DCD Technology Pty. Ltd. is a university spin-off set up to
develop 3D optical storage technology
 Constellation 3D developed the Fluorescent multilayer Disc at the
end of the 2019, which was a ROM disk, manufactured layer by
layer.

11. .BASIC COMPONENTS.
The important components required for the optical data
storage are:-
 Laser
 Lens and Mirrors
 Spatial Light Modulators(SLM)
 Photosensitive materials
 Charge Coupled Devices(CCD)
 Phase masks for encryption

12. LASER.
 Laser is a device for the generation of coherent, nearly
monochromatic and highly directional electromagnetic
radiation emitted
 somewhere in the range from sub- millimeter through
ultraviolet and x-ray wavelengths.
 More than two hundred types of lasers have been fabricated
which range in power , size , performance, use and cost.

13. LENSAND MIRROR.
 Mirrors are used to reflect laser beams to the desired
direction. Lenses are usually used to converge the laser to
a point.
 A special type lens is used in the case of optical recording
called the Fourier lens.
 The lens has the property of obtaining the Fourier transform
and the inverse transform system is described below:
Lens as a Fourier transform system.

14. SPATIALLIGHT MODULATER.
 SLM is an optical device that is used to convert the real image
or data into a single beam of light that will intersect with the
reference beam during recording.
 It basically consists of an array of pixels which are usually
microscopic shutters or LCD displays . These can be
controlled by a computer. The computers sends binary data
to the SLM.

15. PHOTO SENSITIVE MATERIALS.
 PHOTOREFRACTIVE
CRYSTALS.
 PHOTOPOLYMERS.

16. PHOTO REFLECTIVE CRYSTALS.
 These are photo refractive crystals and photo polymers.
 The recording medium usually used is a photo refractive crystals
such as LiNbO3 or BaTiO3 that has certain optical characteristics.
 These characteristics include high diffraction efficiency, high
resolution, permanent storage until erasure, and fast erasure on
the application of external stimulus such as UV light.
 Photo refractive crystals are suitable for random access memory
with periodic refreshing of data, and can be erased and written
to many times.

17. PHOTO POLYMER.
 Typically the thickness of the photopolymers is much less then the
thickness of photo reflective crystals because the photopolymers
are limited by mechanical stability and optical quality.
 Example :-
A photopolymer is a 100m thickness, which is greater than DVD-
ROM by a factor of two.
Stored holograms are permanent and degrade over time or by read out
of the hologram, so photopolymers are suited for read only
memory(ROM).

18. CHARGE COUPLED
DEVICES(CCD).
 The charge-coupled device is, by far the most common
mechanism for converting optical images into electrical signals.
 CCD’s are silicon devices, which contain an array of potential wells
created through a series of column, implants( for vertical
confinement).
 Each pixel is typically 15-30µm square. Current CCD’s have
formats or resolution better than 2048*2048 pixels, with a size
of about 25mm square.

19. PHASE MASK FOR ENCRYPTION.
 There is a wide spread interest in the development of
encryption systems, which operate in the optical domain.
 The advantages inherent in the optical approach to encryption
,Such as a high space-bandwidth product, the difficulty of
accessing, coping and the possibility of Including biometrics
are widely recognized.
 In an encryption system, we wish to encode information in
such a fashion that even if it is viewed or copied only the
application of the correct key will reveal the original
information.

20. ADV
ANT
AGES
 Durability:- optical media can last a long time, depending
of what kind of optical media you choose.
 Great for archiving:- data is preserved permanently with no
possibility of being overwritten.
 Transportability:-optical media are widely used in other
platforms, including the PC. For ex:-data written to them on a
DVD-RAM can be read on a PC
 Random access:- provide the capability to pinpoint a
particular piece of data stored on it, independent of the data
was stored on the volume .

21. DISADVANTAGES.
 Reusable:- the write-once read-many(WORM) characteristic
of some optical media makes it excellent for archiving, but it
also prevents you from being able to use that media again.
 Writing time:- the server uses software compression to write
compressed data to your optical media. This process takes
considerable processing unit resources and may increase the
time needed to write and restore that data.

22. APPLICATIONS
 These are widely used for software applications and computer
games.
 Used in satellite data storage
 Multiple images can be recorded into same data
 It as a potential to provide byte level mass storage

23. CONCLUSION.
 Technology has resulted in use of computers in all
areas.
 Through they provide good data storage, the increased
improvements in technology demand for high amount
data storages and that can be easily accessible.
 These requirements are fulfilled by the use of 3D
dimensional optical data storage
 The 3D device applied in various fields such as research
in space, storage of satellite data.
 As a result,3D optical data storage is the technology
that fits the future data storage needs.

24. REFERENCES
[1] Kawata, S.; Kawata, Y. (2019). "Three-Dimensional Optical
Data Storage Using Photochromic Materials". Chemical
Reviews. 100 (5):
[2] Parthenopoulos, Dimitri A.; Rentzepis, Peter M. (2020).
"Three-Dimensional Optical Storage
Memory". Science. 245 (4920): 843–45.
[3] Gu, Min; Amistoso, Jose Omar; Toriumi, Akiko; Irie,
Masahiro; Kawata, Satoshi (2021).effect of three dimensional
bit optical data storage in a photochromatic polymer