This document discusses optical storage and 3D optical data storage. It describes how optical storage works by using lasers to burn data into optical disks in a spiral track. 3D optical storage can store data in three dimensions rather than two, potentially storing much more data in the same physical space. Some challenges to commercializing 3D optical storage have been destructive reading processes and issues with media stability and sensitivity. The document outlines the basic components, processes, and form factors of 3D optical storage systems.

1. M. Abhinaya
19841A0582
CSE-4B

2.  Introduction
 Media and Drive Design
 Basic Components
 Processes for creating written data and for reading data
 Media Form Factor
 3D photonic crystals optical-memory systems
 Commercial Development
 Applications
 Advantages
 Conclusion

3. OPTICAL STORAGE:
 Conventional storage systems make use of magnetic and semiconductor
technologies for data storing in CDs and DVDs. Optical data storage is
different from that.
 The storage is done on an Optical Readable Medium.
 An optical drive writes data on the optical readable medium i.e., a storage
disk.
 The storage disk then uses a laser beam to burn pits(bumps) into the special
material on disk.

4.  This data stream is placed in a Spiral path, in this case the data begins at
the innermost track and works its way towards the edge of the disk.
 An optical drive is a device in a computer that can read CD-ROMs or other
optical disks.
 It is estimated that in the year 2007, optical storage represents 27% of the
world's technological capacity to store information.

5.  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 (as opposed to the two dimensional resolution afforded, for
example, by CD).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.

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.
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, particularly if the form
factor and data structure of the media is similar to
that of CD or DVD.

7.  Optical data storage system requires certain important materials for its data
storage and retrieval processes. 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

8. PROCESSES FOR CREATING WRITTEN DATA
 Data recording in a 3D optical storage medium requires that a change take
place in the medium upon excitation. If the photochemical change is
reversible, then rewritable data storage may be achieved.
PROCESSES FOR READING DATA
 Reading of data from 3D optical memories has been carried out in many
different ways.
- Measurement of small differences in the refractive index between the
two data states.
- Linear excitation of fluorescence - has some potential problems because
the addressing light interacts with many other data points.

9.  Media for 3D optical data storage have been suggested in several form
factors:
 Disc: A disc media offers a progression from CD/DVD, and allows
reading and writing to be carried out by the familiar spinning disc method.
 Card: A credit card form factor media is attractive from the point of
view of portability and convenience, but would be of a lower capacity than
a disc.
 Crystal, Cube or Sphere: Several science fiction writers have
suggested small solids that store massive amounts of information, and at
least in principle this could be achieved with 3D optical data storage.

10.  Different modifications of 3D optical memory units based on photonic
band-gap structures can be proposed, depending on the arrangement of
writing and reading beams in space, as well as on whether a one-, two-, or
multi photon process is used to produce the luminescence readout signal.

11.  Despite the highly attractive nature of 3D optical data storage, the
development of commercial products has taken a significant length of time.
This results from limited financial backing in the field, as well as technical
issues, including:
 Destructive reading
 Thermodynamic stability
 Media sensitivity

12. Wide chance of storing data in a less space such as
 DVD
 Servers
 Databases
 Social networking
and so on as we need to save the data…………

13.  Durability: With proper care, optical media can last a long time,
depending on what kind of optical media you choose.
 Great for archeiving: Several forms of optical media are write-once read-
many, which means that when data is written to them, they cannot be
reused.
 Transportability: Optical media are widely used on other platforms,
including the PC. For example, data written on a DVD-RAM can be read
on a PC or any other system with an optical device and the same file
system.
 Random access: Optical media provide the capability to pinpoint a
particular piece of data stored on it, independent of the other data on the
volume or the order in which that data was stored on the volume

14.  3D optical data storage is the form of optical data storage which is really a
good alternative for the data storage required in now-a-days life which is
having a lot of data to store, as it can store about 217 DVD’s in a single
disc.
 Its potential applications for storing and archiving of data that was
previously erased for economic reasons holographic disks.
 Ultra HD Sony and other big companies are interested in this technology.

15.  http://en.wikipedia.org/wiki/3D_optical_data_storage
 http://www.riken.jp/lab-
www/library/publication/review/pdf/No_49/49_052.pdf
 Hunter, S., Kiamilev, F., Esener, S., et al., 1990, Appl. Opt., 29, 2058.
 Parthenopoulos, D.A and Rentzepis, P.M., 1989, Science, 245, 643.
 Dvornikov, A.S., Cokgor, I., McCormick, F.B., et al., 1996, Opt. Commun.,
128, 205.