Sharp DV-560H (serv.man6) Service Manual ▷ View online
2
DVD-Series
3
DVD-Series
1. The Birth of DVD
1-1 Main Specifications of the DVD Video Player
Disc Diameter
120mm
Disc Thickness
1.2mm 0.6mm x 2
Semiconductor Laser Wavelength
650nm
Lens (NA)
0.6
Pit Length
0.4~1.87
µ
m
/
0.44~2.05
µ
m
(Single Layer)
(Double Layer)
Track Pitch
0.74
µ
m
Sector Allocation
CLV
Modulation System
8/16 Modulation
Correction System
RS-PC (Reed Solomon Product Code)
1
4.7GB (1 Layer on 1 Side)
Memory Capacity
2
8.5GB (2 Layers on 1 Side)
3
9.4GB (1 Layer on Both Sides)
4
17GB (2 Layers on Both Sides)
1-2 Type of Discs
There are 4 types of discs.
(1) 1 layer on 1 side disc
(2) 1 layer both sides disc
(3) 2 layers on 1 side disc
(4) 2 layers on both sides disc
0.6mm
0.6mm
0.6mm
0.6mm
,,,,,,,
Side A
Side B
0.6mm
0.6mm
0.6mm
0.6mm
First layer
First layer
Second layer
Second layer
First layer
Second layer
4
DVD-Series
1-3 Disc Structure
The first layer on the 2-layers disc (semitransparent reflection film) does not reflect unless the laser
light is focused.
light is focused.
(1) 1 layer on both sides
(2) 2 layers on 1 sides
1-4 Disc Capacity
1 layer on 1 side
2 layers on 1 side
1 layer on both sides
2 layers on both sides
12cm
4.7
8.5
9.4
17
8cm
1.4
2.6
2.9
5.3
1-5 Example of the DVD’s calculating memory capacity Condition
Condition
1. More than 3.5Mbps of average image data rate
(The compression rate changes depending on the image. This is the average value)
2. Audio is Dolby AC-3, 5.1ch digital sound
3. Dubbed in 3 languages + subtitled in 4 languages
4. 133 minutes are recorded on a 1 layer on 1 side disc
3. Dubbed in 3 languages + subtitled in 4 languages
4. 133 minutes are recorded on a 1 layer on 1 side disc
Required data rate
Image
Audio
Subtitles
Total
3,500k
+
(384k
×
3)
+
(10k)
=
4,692kbps(bit/second)
Required disc capacity
Data Rate
Recording Duration
Memory Capacity
4, 692kbps
×
(133
×
60) second
÷
8 (8bit = 1byte)
=
4.680.270kBytes
4.7 gigabytes are required to record 133 minutes on a 1 layer on 1 side disc
Type of Disc
Disc Size
,,,,,,,,,,,
,,,,,,,,,,,
0.6mm
0.6mm
Side B
(Standard reflection film)
(Standard reflection film)
Adhesive layer
Side A
(Standard reflection film)
(Standard reflection film)
,,,,,,,,,,,
,,,,,,,,,,,
0.6mm
0.6mm
Second layer
(Standard reflection film)
(Standard reflection film)
Adhesive layer
(transparent)
(transparent)
First layer
(semitransparent reflection film)
(semitransparent reflection film)
5
DVD-Series
1-6 Order and Direction of Disc Recording
There are 3 types of recording orders and directions.
1 layer disc
2 layers disc (B)
1-7 Two Discs are Stacked Together to Form DVD discs
The DVD disc structure is the stacking of two 0.6mm thin type discs, making it most suitable for
reading high density recorded data signals.
The thinner the disc, the less number of obstacles between pits notched on the optical pick up and
disc, so more precise reading can be achieved.
Additionally, stacking these same material discs together back-to-back, increases evenness,
meaning the disc will warp less due to heat and humidity compared to single 1.2mm boards. Thus,
the discs are more reliable.
reading high density recorded data signals.
The thinner the disc, the less number of obstacles between pits notched on the optical pick up and
disc, so more precise reading can be achieved.
Additionally, stacking these same material discs together back-to-back, increases evenness,
meaning the disc will warp less due to heat and humidity compared to single 1.2mm boards. Thus,
the discs are more reliable.
Features of the 0.6mm Thick Disc
1. Materialized mass capacity and high density
• Because the thickness is half that of traditional discs, it is less likely to warp or slant.
• Degree of evenness becomes much higher at assembly, with high rates of evenness and
• Degree of evenness becomes much higher at assembly, with high rates of evenness and
precision.
2. Makes board-making easier and reduces production costs
• The stacked structure is highly resistant to environmental changes (heat, humidity)
• The thin structure increases the time cycle, so forming is easier stabilized
• Overall, it will cost less than 20% more than a CD.
• The thin structure increases the time cycle, so forming is easier stabilized
• Overall, it will cost less than 20% more than a CD.
2 layers disc (A)
,,
,,
,,,,
,,,,
2
1
Data area
Lead-in area
Lead-out area
Parallel track path
Center of the disc
,,
,,
Center of the disc
Lead-in area
Data area
Lead-out area
,,
,,,
2
1
Data area
Lead-in area
Lead-out area
Middle area
Opposite track path
Center of the disc
0.6mm
0.6mm
1.2mm
Changes in temperature and humidity
DVD (stacked-together structure)
CD (single board structure)
