2. EVOLUTION:
• VHS: analog
DVD: digital
BD: high-definition.
• Enables recording,
rewriting, and playback of
high-definition video.
• Capable of storing
information that the DVD
and CD are not capable of
holding
3. HISTORY
• BLU-RAY disc (BD) is appropriately named after
the blue laser used to write the data.
• The first blue laser was developed in 1996 by Shuji
Nakamura (Nichia Corporation).
• In 2002, an alliance was formed, called the BLU-
RAY Disc Association, including the likes of
Sony, Samsung, Sharp, Hewlett-Packard, and Royal
Phillips
• The “e” is intentionally left out of the name due to
trademark restrictions.
4. Disc Characteristics
The power conservation
allows the development of
multi-layer platforms and
high-speed recording.
BD-ROM: read-only format.
BD-R and BD-RE:
recordable formats (RE:
rewritable; R: recordable
once).
5. Disc Characteristics
Numerical Aperture measures the ability of a lens to gather
and focus light. As the numerical aperture increases, the
focusing power increases and the beam size decreases.
Phase change implies that the disc section is either an
amorphous or crystalline state. The reflectivity changes
accordingly thus representing a binary bit.
6. Comparison: CD, DVD & Blu-ray Disc
Due to the fact that the data layer on a Blu-ray Disc
is placed much “closer” to the laser lens than in DVD
, there is less distortion resulting in significantly
improved tolerances. Hence, more precision and ultra
high storage densities are made possible.
8. Compatibility
This issue has introduced a competitor, the HD-DVD, that
based its technology around being compatible with the DVD.
Recently the BDA has developed recorders that are
BD/DVD/CD compatible.
JVC has advanced the BD by developing a BD/DVD combo
disc that stores both DVD and BD data. It is composed of two
DVD layers and a third BD layer storing 33.5 GB total.
9. Protection System
HDTV contains a copyright bit that is
detected by the BD recorder. If the broadcast
has no copyright bit, then the BD recorder is
allowed to store the information.
Uses the Data Encryption Standard (DES)
that has a key length of 56 bits.
A Key Block and Disc ID are written into the
ROM area to prevent illegal copying.
10. Enhancements
Error rates increased in reading and writing after the
original BD suffered scratches and fingerprints.
For protection, the prototype BD was enclosed in a
case.
The case increased the size of the disc drive.
11. Enhancements(conti.)
A hard coat was derived
of an ultraviolet-curable
resin that has a scratch
resistance similar to the
DVD.
An artificial fingerprint
reagent is placed on the
disc surface to resist
fingerprint oils.
17. Future
Expect the BD to become more prevalent once the HDTV market establishes
its presence.
Audio and video will reach higher qualities with larger storage space.
Look for BD with more than two layers as the technology is further refined.
Sony has made the Disc with size 200GB already.
Pioneer announced on August 5, 2008 , that they have got success in making
BD with increased Disc Size of 500GB.
