Philips Blu Ray Schematic

Training Manual

Basics

Blu Ray Disc

January 2007

Basics of Blu Ray
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Table of Contents

1. Physical Format Blu Ray Disc........................................................................................ 3

1.1 Introduction............................................................................................................... 3

1.2 Basic Parameters....................................................................................................... 4

1.3 0.1-mm-thick Cover.................................................................................................. 5

1.4 Dual Layer Disc........................................................................................................ 6

1.5 Hard Coating............................................................................................................. 6

1.6 Addressing Method and Tracking Format................................................................ 7

1.7 Physical format BR-ROM......................................................................................... 7

2. Audio Visual Application for BD-ROM......................................................................... 8

Introduction..................................................................................................................... 8

2.1 Introduction to HDMV Mode....................................................................................... 8

2.1.1 Core functions........................................................................................................ 8

2.1.1.1 Out of Mux stream Framework....................................................................... 8

2.1.1.2 Graphics Framework....................................................................................... 9

A) Graphics planes.................................................................................................... 10

B) Graphics model.................................................................................................... 10

C) Graphics animations............................................................................................. 11

2.1.1.3 Text Subtitle Framework .................................................................................. 12

2.1.1.4 Interactivity Framework.................................................................................... 15

1 Pop-Up Menus....................................................................................................... 15

2 Always On Menus.................................................................................................. 15

3 Multi Page Menus.................................................................................................. 16

4 Button enabling and disabling ............................................................................... 16

3.1 Introduction to BD-J mode. ........................................................................................ 18

3.2 Core Functions........................................................................................................ 18

3.2.1 Application Execution / Management ............................................................. 18

3.2.2 GUI framework and User Interface ................................................................. 19

3.2.3 Device model & functions like HAVi ............................................................. 19

3.2.4 AV Playback and Navigation and Subtitle/Audio Language Control............. 19

3.2.5 Other (static) content format functions (Graphics, Text, Audio Clips)........... 20

3.2.6 Access control, security scheme, application authentication scheme.............. 20

3.2.7 Internet Connectivity & Download of New Contents/Applications................ 20

3.2.8 System/Local Storage ...................................................................................... 20

3.2.9 Binding scheme for on-the-disc and off-the-disc content................................ 21

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1. Physical Format Blu Ray Disc.

1.1 Introduction.

Blu-ray, also known as Blu-ray Disc (BD), is the name of a next-generation optical disc format
jointly developed by the Blu-ray Disc Association (BDA), a group of the world's leading consumer
electronics, personal computer and media manufacturers (including Apple, Dell, Hitachi, HP, JVC,
LG, Mitsubishi, Panasonic, Pioneer, Philips, Samsung, Sharp, Sony, TDK and Thomson). The
format was developed to enable recording, rewriting and playback of high-definition video (HD),
as well as storing large amounts of data.

Figure 1

The standards for 12-cm optical discs, CDs, DVDs, and Blu-ray rewritable discs (BD-RE
Standard) were established in 1982, 1996, and 2002, respectively. The recording capacity
required by applications was the important issue when these standards were decided. The
requirement for CDs was 74 minutes of recording 2-channel audio signals and a capacity of about
800 MB. For DVDs, the requirement as a video disc was the recording of a movie with a length of
two hours and fifteen minutes using the SD (Standard Definition) with MPEG-2 compression. The
capacity was determined to be 4.7 GB considering the balance with image quality.

In the case of the Blu-ray Disc, abbreviated as BD hereafter, a recording of an HDTV digital
broadcast greater than two hours is needed since the BS digital broadcast started in 2000 and
terrestrial digital broadcast has begun in 2003.

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Video

Length

Bit Rate

high=qualit

x =

y

Audio

Length

x

Bit Rate

high=quality

Lang/

Tracks

x+

Required
Capacity

Average

Film:

Lord of the

Rings: Return

of the King:

This example indicates that high bitrates (to obtain good picture quality) lead to disc capacity of
25 GB per disc or per layer.

135 min

250 min

x

15 Mbps

(pristine picture quality)

15 Mbps

x

(pristine picture quality)

+

+

135 min

250 min

xx=

3 Mbps

(high quality)

3 Mbps

xx=

(high quality)

3 Tracks

3 Tracks

24.3GB

45GB

1.2 Basic Parameters.

To come to a disc with high capacity it is necessary to know the basic parameters.

In principle, the recording capacity of an optical disc is determined by the spot size, which is
proportional to the light-source wavelength λ and inversely proportional to the numerical aperture
(NA) of objective lens. The capacity, which is in inverse proportion to the square of spot size, can
be expressed as follows:

Capacity ∝ ( λ / NA)2

To increase the capacity is possible by decreasing the wavelength
and increasing the NA. Decreasing the wavelength is possible by
using a GaN laser diode that provides a wavelength of 405 nm. A
DVD with 650 nm wavelength and 0,6 NA can be increased 2.5
times by decreasing the wavelength to 405 nm. The capacity
increases to max. 15 GB. (The HD-DVD uses this technology).
Increasing the NA to 0,85 the capacity of a DVD can be increased
five times.
Blu-ray Disc provides approximately 25 GB recording capacity.

Figure 3

The Blu-ray Disc system has the following three basic parameters:

• Laser wavelength: 405 nm

• Objective-lens numerical aperture (NA): 0.85

• Cover thickness: 0.1 mm

Figure 2

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1.3 0.1-mm-thick Cover

As discussed in the previous section, Blu­ray Disc (BD) employs a higher-NA
objective lens and a
shorter-wavelength laser to increase the
recording density. To enable this, the cover
thickness is set to 0.1 mm, taking account of
tilt margin, resistance to damage by dust,
and disc production
process. A comparison of diameter and
intensity distribution of a concentrated beam
on a disc between a CD and a DVD is
shown in the next figure. Since the integral
of this waveform is the recording energy on

an optical media, the energy is supposed to
be input to the objective lens. Assuming the
recording on the media begins with the same energy, the smaller the diameter (that is, the higher
the density), the less the necessary laser power. This is one of reasons why Blu-ray requires only
5 mW for recording while CDs and DVDs require several tens of mW for a similar recording
speed.

Figure 4

Figure 5

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1.4 Dual Layer Disc.

With regard to the dual layer DVDs, read-only (ROM) disc is specified. However, in the Blu-ray
(BD) standards, dual layer system is also defined for rewritable type discs. BD provides large
recording capacities such as 46.6/50/54 GB (23.3/25/27 GB per layer). More than 4 hours of
HDTV and more than 20 hours of SDTV can be recorded respectively. In addition, since
recording and playback can be done from one side, user does not have to turn the disc over in
the drive. Next figure shows a schematic drawing of the dual layer BD disc. In the BD standard,
an information recording layer 100 μm away from the laser incident plane is defined as the L0
layer, and another information recording layer 75 μm away is called as the L1 layer. A phase
change material is used as the recording media because of prior experience with DVD-RAM,
DVD-RW, etc.

Figure 6

1.5 Hard Coating.

BD is much more sensitive to scratches and fingerprints compared with DVD. Slight scratch or
fingerprints will cause deterioration of error rates and/or loss of a tracking servo control. To avoid
such problems, the first generation BD-RE (ver1.02) is protected with a cartridge case. A bare

disc, however, is desired in order to downsize a disc drive. In
addition, it is preferred to reduce the media manufacturing cost by
making them cartridge-free.
Thus the hard-coat technology for the bare discs has been
explored, aiming mainly at scratch- and fingerprint-resistances. A
light-transmitting layer consists of a 98 μm thick cover layer
and a 2 μm thick hard-coat.

Regarding the problem of fingerprints, you may accidentally put

your fingerprints on a blank disc before setting it on a recorder.
Generally data signals recorded over fingerprints contain much more errors than
ROM data signals read through fingerprints. This is the reason that fingerprint-resistance is
viewed as more crucial property in BD-RE or BD-R, compared to BD-ROM.

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1.6 Addressing Method and Tracking Format.

Blank addressing, is formed only by the wobble
method. This concept is close to that employed for
+RW. The tracking format of Blu-ray Disc is groove­recording, i.e., writing recording data only in on groove
tracks. For the groove recording method, lands are
sandwiched between adjacent grooves to block heat
transfer between the grooves, preventing signal quality
deterioration due to the influence of data recording in
adjacent groove tracks with a narrow track pitch. The
track pitch between grooves in Blu-ray Disc is 0.32
μm. The modulation technique wobbling in the radial
direction is based on MSK (minimum shift keying) and
formatted in blocks of 64 kB. The basic Wobble
frequency is around 5 μm, and 0 and 1 are expressed
as the position where the sinusoidal wave is

modulated by the MSK rule. Although the modulation
energy of MSK is large, it is easily influenced by
defects because information is localized.
For that, a signal called STW (Saw Tooth Wobble) is used in form of multiplying to MSK. The
STW adds secondary harmonics to all sinusoidal waves of Wobble, and 0 and 1 of the address
data correspond to the polarity of added secondary harmonics. Since the energy of the STW
signal is distributed in space unlike that of MSK, and detected by integration, it is robust against
partial defects. The detection of an address in
the Blu-ray system is robust because of the use of both MSK and STW.

Figure 7

1.7 Physical format BR-ROM

Figure 8

The various capacities of BD-ROM discs are shown in Figure 8. As you can see from
This figure, most movie applications can be recorded on a single layer disc. Dual layer discs
expand the application range even more.

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