What's a blu-ray disc – Panasonic DMP-BD10 User Manual

Page 9

Advertising
background image

9

What's a Blu-ray Disc?

Structure of the BD-Video Disc

Benefits of the BD-Video Disc

The Blu-ray Disc (BD) is a next-generation optical disc format for storing a large amount of data

using a short wavelength blue laser to read and write. Like DVD, there are a number of BD

standards, such as read-only BD-ROM, recordable BD-R and rewritable BD-RE.

The single largest feature of BD is its high-density data storage capacity of 25 GB

#

per layer on

one side. This lets you store many hours of content, such as movies with HD resolution and

high-quality music with loss-less audio compression. BD also features a high-performance

interactive function that uses Java

TM

, called BD-J, to deliver a new video experience to users not

offered by conventional video media. With many motion picture production companies and

electronics, PC and gaming manufacturers expressing their support for BD, new hardware and

software products are expected to hit the market soon.

650nm

0.6

120mm

1.2mm
0.6mm

0.74

μm

4.7GB

#

8.5GB

#

10.08Mbps

Laser Wavelength

Numerical Aperture (NA)

Disc Diameter

Disc Thichness

Protection Layer

Track Pitch

Capacity (Single-layer)

Capacity (Dual-layer)

Data Transfer Rate

405nm

0.85

120mm

1.2mm
0.1mm

0.32

μm

25GB

#

50GB

#

48Mbps

DVD

BD-Video Disc

C

L

R

RS

LS

SBL

SBR

SW

Compression methods

Maximum data transfer rate

Resolution and frame rate

MPEG-2
MPEG-4 AVC
SMPTE VC-1

48 Mbps

1920 x 1080

59.94i, 50i, 23.976p, 24p

1440 x 1080* 59.94i, 50i, 23.976p, 24p
1280 x 720

59.94p

720 x 480

59.94i

720 x 576

50i

BD-ROM Video Formats

*AVC/VC-1 only

1.2 mm

0.6 mm

100%

19%

DVD(4.7GB)

BD-Video(25GB)

Lens numerical aperture: 0.6
Laser wavelength: 650 nm

Lens numerical aperture: 0.85
Laser wavelength: 405 nm

Substrate

Substrate

Minimum pit length
0.4 µm

Track pitch 0.74 µm

Recording layer

Track pitch 0.32 µm

Optical spot area ratio

Cover layer
0.1 mm

Minimum
mark length
0.149 µm

The Blu-ray Disc is an optical disc with the same dimensions as the DVD disc: 12 cm in diameter and 1.2 mm in thickness. By using a

combination of the 405-nm-wavelength blue-violet laser, which is a shorter wavelength than the red laser used by DVD, and a high-density

objective lens with a numerical aperture of 0.85, BD uses a laser beam spot that is only about 1/5 the size used by DVD. Thanks to these

technologies, a single-layer BD-Video disc can store five times more data than a DVD disc.

1. One Single-Layer Disc Equals Five DVDs in Data Capacity

The BD-Video disc boasts a data storage capacity of 25 GB

#

in a single

layer and 50GB

#

in dual layer, because it uses the shorter wavelength

blue-violet laser and a high-density objective lens to enable

higher-density data reading. When a multi-layer system is adopted in the

future, the storage capacity can increase to 100 GB

#

and even 200 GB

#

.

One BD-Video disc can store a huge amount of data so users can enjoy

many hours of high-definition content and high-quality surround sound

that could not previously be provided by other media.

2. HD Image Quality Video

In addition to the MPEG-2 format used by DVD-Video, the BD-Video disc

uses video codes, such as MPEG-4 AVC and VC-1, which deliver high

image quality using high compression rates. The data transfer speed is

48 Mbps, which is about three times faster than DVD. A future plan also

calls for a further increase in the data transfer speed. These technologies

allow long-time playback of content with high-definition image quality.

4. BD-J for Extensive Interactive Functions

The BD-Video disc is equipped with an extended function based on

Java

TM

technology, called BD-J, to provide various interactive features.

For example, this can be used to program various operations, such as

displaying a pop-up menu while playing a BD-Video disc, and

activating a keyword search. With unlimited application possibilities,

BD-J offers interactive enjoyment that is simply not possible with

conventional AV software.

5. Extensive Support for Both Hardware and Software

The Blu-ray Disc specifications have been established mainly by leading

electronics, PC and gaming manufacturers around the world, including

Panasonic. These companies will support BD promotion by introducing a

variety of hardware. A number of major motion picture production

companies have expressed their support. A variety of software can be

expected to hit the market before long.

3. High-Quality Surround Sound

The BD-Video disc optionally supports next-generation surround sound formats like Dolby

®

Digital Plus.

Connecting a BD-Video player to an AV centre using an HDMI* cable enables linear PCM multi-channel

data transfer. This makes it possible to reproduce high-quality 7.1-channel surround sound with each

channel offering DVD-Audio quality, delivering a surround sound experience that rivals the quality of the

master audio source.

* HDMI Ver. 1.1 and newer.

BD-Video

1 disc

DVD

5 discs

CD

35 discs

Java is a trademark of Sun Microsystems

# 1GB=1 billion bytes. Useable capacity will be less.

Java is a trademark of Sun Microsystems.

Advertising