Physical parameters Of DVD
| Capacity |
| Parameter
| Units
| DVD
| CD |
| max payload
| GBytes
| 4.7 (12 cm SL)
8.54 (12 cm DL)
1.46 (8 cm SL)
2.66 (8 cm DL)
| 0.742 (mode
2)
0.650 (mode 1) |
| Data rates |
| channel rate
| mbit/sec
| 26.16
| 4.3218 |
| FEC rate
| mbit/sec
| 3.00
| 0.4704 |
| user rate
| mbit/sec
| 11.08
| 1.47 |
| actual data rate
| mbit/sec
| 10.08
| 1.4112 |
| Pits and tracks |
| pit width
| micron
| 0.5???
| 0.5 |
| track pitch
| micron
| 0.74
| 1.6 |
| Min pit length
| micron
| 0.40 (SL)
0.44 (DL)
| 0.833 to 0.972 |
| Max pit length
| micron
| 1.87 (SL)
2.13 (DL)
| 3.054 to 3.560 |
| min pit length
| -
| 2T
| 2T |
| max pit length
| -
| 10T
| 10T |
(Note: the minimum pit length for
each layer of the Double layer disc is 10% greater than single layer
disc. Hence the 10% less dense figure for Dual layer discs.)
| Data format |
| sector size
| bytes
| 2048
| 2352 (mode
2)
2048 (mode
1) |
| Movement |
| Spiral direction
|
| clockwise
| clockwise |
| max revolutions/sec
| Hz
| 25.5 (12 cm disc)
| 8 (12 cm disc) |
| min revolutions/sec
| Hz
| 10.5
| 3.5 |
| Reference scanning velocity
| m/s
| 3.49 (SL)
3.84 (DL)
| 1.2 to 1.4 |
| Optics |
| wavelength
| nm
| 650 or 635
| 790 |
| Numerical Aperture
of Objective Lens
| -
| 0.60
| 0.45 |
| refractive index
| -
| 1.55
| 1.55 |
Spot Size
(lambda/NA)
| -
| 0.63
| 1 |
Focus Depth
(Focus Margin, lambda/NA^2)
| -
| 0.47
| 1 |
Chromatic Aberration
(Title margin, lambda/NA^3)
| -
| 0.35
| 1 |
Spherical Aberration
(Thickness Tolerance, lambda/NA^4)
| -
| 0.26
| 1 |
| Reflectivity
| %
| 70 minimum (SL)
25 to 40 (DL)
| 70 minimum |
| Mass |
| Thickness of substrate
| mm
| 0.6
| 1.2 |
| disc thickness
| mm
| 1.2
| 1.2 |
| disc mass
| grams
| 13 to 20 (12 cm)
6 to 9 ( 8 cm)
| 14 |
| Thickness of spacing layer in Dual Layer
| micron
| 40 to 70
| N/A |
| FEC |
| Error correction
| method
| RS product
code
| CIRC |
| FEC consumption
| %
| 13
| 25 |
| FEC format
| bytes
| (208,192,17)x(182,172,11)
| (28/32)x(24/28) |
| Sector constraint length
| -
| 16 (=32 Kbytes)
| 1 |
| correctable burst length
| mm
| 6.0 (SL)
6.5 (DL)
| 2.5 |
| Channel code |
| Channel modulation
| method
| 8/16 (EFM+)
| 8/14 + 3 merge bits |
| Run length
| bits
| (2,10)
| (3,11) |
| Diameters |
| outer
| mm
| 120 (12 cm)
80 (8 cm)
| 120 |
| outer lead in
| mm
| 117 (12 cm)
78 (8 cm)
| 117 |
| outer data
| mm
| 116 (12 cm)
76 (8 cm)
| 116 |
| inner data
| mm
| 48 (12 cm)
48 (8 cm)
| 50 |
| inner lead in
| mm
| 45 (12 cm)
45 (8 cm)
| 46 |
| center hole
| mm
| 15 (12 cm)
15 (8 cm)
| 15 |
|
