ECMA-378 1st Edition / May 2007
Information Interchange on Read-Only Memory Holographic Versatile Disc (HVD-ROM) – Capacity: 100 Gbytes per disk
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© Ecma International 2007
Standard ECMA-378 1st Edition / May 2007
Information Interchange on Read-Only Memory Holographic Versatile Disc (HVD-ROM) – Capacity: 100 Gbytes per disk
Ecma International F
ECMA 378
Rue du Rhône 114
CH-1204 Geneva
T/F: +41 22 849 6000/01
www.ecma-international.org
NOTIFICATION AND DISCLAIMER Ecma international draws attention to the possibility that the practice, use or implementation of this Ecma Standard or of parts thereof may involve the use of one or more Intellectual Property Rights, in particular such as a patent or a patent application. Ecma International takes no position concerning the existence, evidence, scope of protection, validity or applicability of any or all of such Intellectual Property Rights, whether asserted by Ecma International members or others outside of the Ecma Standard development process worldwide. In particular, Ecma International does not identify any or all of such Intellectual Property Rights, does not evaluate the scope of protection and validity of any or all of such Intellectual Property Rights, and does not evaluate the question whether the practice, use or implementation of this Ecma Standard or of parts thereof does or does not make use of any or all of such Intellectual Property Rights. Furthermore, Ecma International does not assume – under any circumstances – any responsibility in this respect. Ecma International informs that as of the date of approval of this Standard, Ecma International has received notice of Intellectual Property Rights. Implementers and users are cautioned that this may not represent the latest information which is available and are therefore strongly urged to consult the Ecma International website for further information.
Introduction In October 2004 a group of Companies, known as the HVD Alliance, proposed to Ecma to develop a standard for the first member of a family of holographic media. Ecma adopted this project and Ecma Technical Committee TC44 was established for the standardization of holographic media. This Standard ECMA-378 is the first standard for a read-only holographic disk.
This Ecma Standard has been adopted by the General Assembly in May 2007.
Table of contents Sect io n 1 - G en eral
1
1
Scop e
1
2
Conf orman ce
1
2.1
Hologr aphic dis k
1
2.2
G ener ating s ys tem
1
2.3
Rec eiving s ys tem
1
2.4
Com patibility s tatem ent
1
3
Ref eren ces
2
4
Def in it io ns
2
4.1
as ym m etr y
2
4.2
c as e
2
4.3
c lam ping zone
2
4.4
c over layer
2
4.5
Data Page
2
4.6
Data Page hologr am
2
4.7
Data Page hologr am pitc h
2
4.8
data r eading beam
2
4.9
data r eading ener gy
2
4.10
dis k r ef er enc e plane
2
4.11
entranc e s ur f ac e
2
4.12
Er r or Cor r ec tion Code ( ECC)
3
4.13
f or m at
3
4.14
hologr am tr ac k
3
4.15
hologr aphic dis k
3
4.16
hologr aphic s tor age layer
3
4.17
pac k et
3
4.18
pit
3
4.19
pit layer
3
4.20
pit tr ac k
3
4.21
pix el
3
4.22
Read O nly Mem or y ( RO M) dis k
3
4.23
Reed- Solom on c ode
3
4.24
Ref er enc e Dr ive
3 -i-
4.25
Ref er enc e Patter n
3
4.26
Spec if ic Dis k Inf or m ation ( SDI)
3
4.27
s pindle
3
4.28
Sub- Page
3
4.29
s ubs trate
4
4.30
s ym bol
4
4.31
Sync Mar k
4
4.32
tr ac k
4
4.33
tr ac k pitc h
4
4.34
tr ac k ing/addr es s ing beam
4
4.35
tr ac k ing/addr es s ing r eading power
4
4.36
Us er data Z one
4
4.37
zone
4
5
Conv ent ion s an d n o t at io n s
4
5.1
Repr es entation of num ber s
4
5.2
Nam es
4
6
Acro nyms
5
7
G en eral d escrip t io n
5
8
G eneral requ iremen t
5
Envir onm ents 8.1 O perating envir onm ent 8.1.1 8.1.2 Stor age envir onm ent 8.1.3 T r ans por tation
5 5 5 6
8.2
T em peratur e s hoc k
6
8.3
Saf ety r equir em ents
6
8.4
Flam m ability
6
Ref eren ce Driv e
6
O ptic al s ys tem
6
9 9.1
T r ac k ing and Addr es s ing Channel 9.2 9.2.1 T r ac k ing/addr es s ing beam 9.2.2 T r ac k ing/Addr es s ing/SDI s ignals
8 8 8
9.3 Data Hologr aphic Reading Channel 9.3.1 Reading beam Ref er enc e Patter n 9.3.2 9.3.3 Photodetec tor ar r ay
8 8 9 10
9.4 Conditions f or m eas ur ing the oper ational s ignals 9.4.1 T r ac k ing, Addr es s ing, Spec if ic Dis k Inf or m ation
10 10
- ii -
9.4.2 9.4.3 9.4.4
Data r eading Nor m alized s er vo tr ans f er f unc tions Rotation of the dis k
11 11 11
Sect io n 2 - M ech an ical and p hysical ch aract erist ics
11
10
11
Dimen sio n al, mech anical, an d p h ysical charact eristics o f th e d isk
10.1
G ener al des c r iption of the dis k
11
10.2
Ref er enc e ax is and plane of the dis k
12
10.3
Dim ens ions of the dis k
12
10.4
Clam ping Z one
12
10.5 Mec hanic al c har ac ter is tic s 10.5.1 Mater ial 10.5.2 Mas s 10.5.3 Mom ent of iner tia 10.5.4 Im balanc e 10.5.5 Ax ial def lec tion 10.5.6 Ax ial ac c eler ation 10.5.7 Radial r unout 10.5.8 Radial ac c eler ation 10.5.9 T ilt
13 13 13 13 13 13 13 13 13 14
10.6 O ptic al c har ac ter is tic s 10.6.1 Subs tr ate 10.6.2 Metadata layer 10.6.3 G ap layer 1 10.6.4 Dic hr oic m ir r or layer 10.6.5 G ap layer 2 10.6.6 Hologr aphic s tor age layer 10.6.7 Cover layer 10.6.8 T hic k nes s es of the s tac k of layer s 10.6.9 Bir ef r ingenc e of the s tac k of layer s
14 14 14 14 14 14 14 14 14 16
11
16
In t erface bet w een d isk and d riv e
11.1
Clam ping m ethod
16
11.2
T aper ed c one f or dis k c lam ping
16
11.3
Clam ping f or c e
16
Sect ion 3 - F o rmat o f in f ormat io n
16
12
G en eral d escrip t io n
16
13
T rackin g an d ad dressing in f o rmat io n fo rmat / Sp ecif ic Disk In fo rmatio n f ormat
16
13.1
Pit tr ac k pitc h
16 - iii -
13.2 Pit tr ac k f or m at 13.2.1 Sec tor 13.2.2 Header 13.2.3 Sync 13.2.4 T r ac k ing data 13.2.5 Land
17 17 17 22 22 22
13.3 Spec if ic Dis k Inf or m ation ( SDI) 13.3.1 SDI bytes enc oding
22 23
13.4
23
14
Radial alignm ent Dat a inf ormat io n f o rmat
23
14.1 Data Page hologr am s layout in the s tor age layer 14.1.1 Radial Data Page hologr am pitc h 14.1.2 Data Page hologr am layout within tr ac k s 14.1.3 Z ones / T angential Data Page hologr am pitc h / Num ber of Data Page hologram s per Peapod
23 23 24
14.2 Data Page enc oding 14.2.1 Us er data 14.2.2 Header 14.2.3 Footer 14.2.4 ECC 14.2.5 Sc r am bling
25 25 26 26 26 27
14.3 Digital to im age c onver s ion 14.3.1. 8 bits to 16 bits c onver s ion 14.3.2 Sym bol/Sub- Page
27 27 28
14.4
30
15 15.1
Data Page hologr am - Ref er enc e Patter n Div ision of t h e F o rmat t ed Zo n e
24
30
G ener al des c r iption of the F or m atted Zone
30
15.2 Content/us age of the F or m atted Zone 15.2.1 Z one 0 – Lead- in Z one / Buf f er Zone 1 / T es t Zone / Buf f er Z one 2 15.2.2 Z ones 1 to 15 - Us er data Z one 15.2.3 Z one 16 - Lead- out Z one
30 31 31 31
Sect io n 4 - Ch aract erist ics o f t h e t rackin g /add ressing an d SDI in f o rmat io n
32
16
M et hod of t est in g
32
Envir onm ent
32
16.1
16.2 Us e of the Ref er enc e Dr ive 16.2.1 O ptic s and m ec hanic s 16.2.2 T r ac k ing/addr es s ing beam power 16.2.3 T r ac k ing r equir em ents
32 32 32 32
16.3
32
Def inition of s ignals
- iv -
17
Sign al req u irement s
33
17.1
Ref lec tivity
33
17.2
Norm alized Pus h Pull s ignal
33
17.3
Modulation
34
17.4
Res olution
34
17.5
4T top m odulation
34
17.6 As ym m etr y 17.6.1 As ym m etr y ( 4T - 2T ) 17.6.2 As ym m etr y ( 16T - 4T )
34 34 34
17.7
J itter
34
17.8
Phas e depth
34
Sect io n 5 - Ch aract erist ics o f u ser dat a
35
18
35
18.1
User dat a – M et h o d o f t est in g Envir onm ent
35
18.2 Ref er enc e Dr ive 18.2.1 O ptic s and m ec hanic s 18.2.2 T r ac k ing/addr es s ing r eading power 18.2.3 Data r eading ener gy 18.2.4 T r ac k ing r equir em ents 18.2.5 Relative pos itioning of the f oc us of the data r eading beam and the tr ac k ing/addr es s ing beam 18.2.6 Data detec tion f or tes ting pur pos es
35 35 35 35 35
19
35
19.1 20
M in imum q u alit y o f a Dat a Pag e Reading ener gy dam age
35 35
36
Dat a in t erch an g e req uiremen t s
36
20.1
T r ac k ing
36
20.2
Stor ed data
36
20.3
Us er - r ead data
36
An n ex A ( n o rmat iv e)
M easu remen t o f lig h t ref lect ance
37
An n ex B ( n o rmat iv e)
M easuremen t of biref ring en ce
39
An nex C ( normat iv e)
T ap ered co n e f o r d isk clamp in g
43
An nex D ( normat iv e)
Sp ecif ic Disk In fo rmatio n
45
An n ex E ( n ormat iv e)
ECC
47
-v-
An n ex F ( normativ e)
16 b it s t o Symb o ls co n v ersio n lo o k-u p tab le
51
An n ex G (normat iv e)
F in aliz in g d at a
67
An n ex H ( normat iv e)
T rackin g /Ad d ressin g an d Dat a Read in g Ch ann els charact erist ics
69
Asymmet ry measu ring d ef in it io n
73
An n ex I (normat iv e) An n ex J (informat iv e)
O f f ice en v iro n men t
75
Annex K ( in f ormat iv e)
T ransp o rt at io n
77
Annex L ( in f o rmat iv e)
T rack d ev iat io n measu remen t
- vi -
79
Section 1 - General 1
Scope This Ecma Standard specifies the mechanical, physical, and optical characteristics of a holographic disk that employs holographic storage to enable data interchange between such disks. The disk is of the ROM (Read Only Memory) type providing for stored data to be read a multiplicity of times. The 120 mm diameter disk has a nominal capacity of 100 Gigabytes. This Ecma Standard specifies -
the conditions for conformance testing and the Reference Drive;
-
the environments in which the disks are to be operated and stored;
-
the mechanical, physical and dimensional characteristics of the disk so as to provide mechanical interchangeability between data processing systems;
-
the format of the information on the disk, including the physical disposition of the tracks and data pages, the error correction codes, the modulation methods used;
-
the characteristics of the embossed information on the disk;
-
the characteristics of the holographic information on the disk;
-
the minimum quality of stored data on the disk, enabling data processing systems to read data from the disk.
This Ecma Standard provides for interchange between holographic disk drives. Together with a standard for volume and file structure, it provides for full data interchange between data processing systems. The disks specified by this Ecma Standard may be enclosed in cases according to Standard ECMA-375 as specified therein.
2 2.1
Conformance Holographic disk A holographic disk shall be in conformance with this Ecma Standard if it meets all mandatory requirements specified therein.
2.2
Generating system A system generating a holographic disk for interchange shall be in conformance with this Ecma Standard if it meets the mandatory requirements of this Ecma Standard.
2.3
Receiving system A system receiving a holographic disk for interchange shall be in conformance with this Ecma Standard if it is able to process any stored data on the disk according to 2.1.
2.4
Compatibility statement A claim of conformance with this Ecma Standard shall include a statement listing any other disk standard supported by the system for which conformance is claimed. This statement shall specify the number of the standard(s), including, where appropriate, the disk type(s), and whether support includes reading only or both reading and writing.
-1-
3
References The following Standards contain provisions, which through reference in this text, constitute provisions of this Ecma Standard. At the time of publication, the edition indicated was valid. All standards are subjected to revision, and parties to agreements based on this Ecma Standard are encouraged to investigate the possibility of applying the most recent edition of the following Standards.
4
ECMA-287 (2002)
Safety of electronic equipment
ECMA-328 (2001)
Detection and measurement of chemical emissions from electronic equipment
ECMA-375 (2006)
Case for 120 mm HVD-ROM disks
Definitions For the purpose of this Ecma Standard the following definitions apply.
4.1
asymmetry The deviation between the centre levels of signals generated by two distinct repeating pit and land patterns.
4.2
case The housing that may protect the disk.
4.3
clamping zone The annular part of the disk within which the clamping force is applied by the clamping device.
4.4
cover layer A transparent layer of the disk, which protects other layers.
4.5
Data Page A two-dimensional representation of data.
4.6
Data Page hologram A hologram storing a Data Page.
4.7
Data Page hologram pitch The distance between adjacent Data Page hologram centres in the holographic storage layer, measured in the radial direction (radial Data Page hologram pitch) or in the tangential direction (tangential Data Page hologram pitch).
4.8
data reading beam The beam used to reconstruct the image recorded in the stored hologram.
4.9
data reading energy The optical energy, incident at the entrance surface of the disk, of the hologram reading beam.
4.10
disk reference plane A plane defined by the perfectly flat annular surface of an ideal spindle onto which the clamping zone of the disk is clamped, and which is normal to the axis of rotation.
4.11
entrance surface The surface of the disk onto which the optical beams first impinge.
-2-
4.12
Error Correction Code (ECC) An error-detecting code designed to correct certain kinds of errors in data.
4.13
format The arrangement or layout of information on the disk. The annular area on the disk bearing the format is the Formatted Zone.
4.14
hologram track Track in the storage layer that contains or may contain holograms.
4.15
holographic disk A disk that will accept and retain information in a holographic storage layer.
4.16
holographic storage layer A layer of the disk in which data is stored in the form of holograms. The holographic storage layer may actually consist of a multiple layer stack of different materials or composite materials.
4.17
packet A group of bytes/bits processed together during data encoding/decoding.
4.18
pit A local depression used to store data information.
4.19
pit layer A layer of the disk bearing pits.
4.20
pit track Track in the pit layer that contains pits.
4.21
pixel The smallest independent element of an image.
4.22
Read Only Memory (ROM) disk A disk which can be only read.
4.23
Reed-Solomon code An error detection and/or correction code which is particularly suited to the correction of errors that occur in bursts or are strongly correlated.
4.24
Reference Drive A drive with well defined properties used to test conformance to the Standard of the read parameters of the disk.
4.25
Reference Pattern A light pattern used to generate the Data Page hologram, and reconstitute its image content.
4.26
Specific Disk Information (SDI) Manufacturing information recorded on the disk.
4.27
spindle The part of the disk drive that contacts the disk.
4.28
Sub-Page A subdivision of a Data Page. -3-
4.29
substrate A layer of the disk provided for mechanical support of other layers.
4.30
symbol An encoding data unit of Data Page.
4.31
Sync Mark A pattern of data pixels used for synchronization of Page data.
4.32
track A path that is followed by the focus of an optical beam during exactly one revolution of the disk.
4.33
track pitch The distance between adjacent tracks centrelines, measured in a radial direction.
4.34
tracking/addressing beam The beam used to read the tracking/addressing information.
4.35
tracking/addressing reading pow er The optical power, incident at the entrance surface of the disk, of the tracking/addressing beam.
4.36
User data Zone The zone of the disk intended for storage of user data.
4.37
zone An annular area of the disk.
5 5.1
Conventions and notations Representation of numbers A measured value is rounded off to the least significant digit of the corresponding specified value. For instance, it implies that a specified value of 1,26 with a positive tolerance of + 0,01 and a negative tolerance of - 0,02 allows a range of measured values from 1,235 to 1,275. Numbers in decimal notations are represented by the digits 0 to 9. Numbers in hexadecimal notation are represented by the hexadecimal digits 0 to 9 and A to F in parentheses. The setting of bits is denoted by ZERO and ONE. Numbers in binary notations and bit patterns are represented by strings of digits 0 and 1, with the most significant bit shown to the left. Negative values of numbers in binary notation are given as Two’s complement. In each field the data is recorded so that the most significant byte (MSB), identified as Byte 0, is recorded first and the least significant byte (LSB) last. In a field of 8n bits, bit b (8n-1) shall be the most significant bit (msb) and bit b 0 the least significant bit (lsb). Bit b (8n-1) is recorded first. A binary digit which can be set indifferently to ZERO or to ONE is represented by “x”.
5.2
Names The names of entities, e.g. specific fields, areas, zones, etc. are given a capital initial.
-4-
6
Acronyms ECC HVD HVD R HVD ROM LDPC LSB lsb MSB msb SDI Sync
7
Error Correction Code Holographic Versatile Disc Holographic Versatile Disc Recordable Holographic Versatile Disc Read Only Memory Low Density Parity Check (code) Least Significant Byte least significant bit Most Significant Byte most significant bit Specific Disk Information Synchronization
General description The holographic disk, which is the subject of this Ecma Standard, is made from a substrate bearing a stack of layers. Data is stored onto the disk as holographic fringes in the volume of the storage layer. Data can be read by a focused optical beam. A layer of the disk contains tracking/addressing data carried by embossed pits. This data can be read using the diffraction of a focused optical beam by the pits. The beams access the storage and pit layers through the transparent cover layer of the disk.
8
General requirement
8.1 8.1.1
Environments O p erat in g en v iron men t The operating environment is the environment where air immediately surrounding the holographic disk has the following properties: Temperature
35 °C ± 2 °C
Atmospheric pressure
60 kPa to 106 kPa
Relative humidity
20 % to 80 %
Absolute humidity
25 g/m max.
Air cleanliness
Office environment (see Annex J)
3
No condensation on the holographic disk shall occur. If a holographic disk has been exposed during storage and/or transportation to a condition outside the above values, before use the disk shall be conditioned in the operating environment for a time at least equal to the period during which it has been out of the operating environment, up to a maximum of 24 h. 8.1.2
St o rag e en v iro n men t The holographic disk without any protective enclosure shall not be stored in an environment outside the range allowed for storage. The storage environment is defined as an environment where the air immediately surrounding the holographic disk has the following properties: Temperature
16 °C to 32 °C
Atmospheric pressure
60 kPa to 106 kPa
Relative humidity
20 % to 80 %
Absolute air humidity
25g/m max.
Air cleanliness
Office environment (see Annex J)
3
-5-
No condensation on the holographic disk shall occur. 8.1.3
8.2
T ransp o rt at io n This Ecma Standard does not specify requirements for transportation. Guidance for transportation is given in Annex K.
Temperature shock The holographic disk shall withstand a temperature shock of up to 10 °C when inserted into, or removed from, the drive.
8.3
Safety requirements The disk shall satisfy the safety requirements of Standards ECMA-287 and ECMA-328, when used in the intended manner or in any foreseeable use in an information processing system.
8.4
Flammability The disk and its components shall be made from materials that comply with the flammability class for HB materials, or better, as specified in Standard ECMA-287.
9
Reference Drive The Reference Drive is a drive several critical components of which have well defined properties and which is used to test the read parameters of the disk for conformance to this Ecma Standard. This section gives an outline of all components; components critical for tests in specific sections are specified in those sections.
9.1
Optical system The basic set-up of the optical system of the Reference Drive used for measuring the read parameters is shown in Figure 1a. Different components and locations of components are permitted, provided that the performance remains the same as that of the set-up in Figure 1a. The optical system shall be such that the detected light reflected from the entrance surface of the disk is minimized so as not to influence the accuracy of the measurements. The combination of the polarizing beamsplitter PBS2 and quarter-wave plate separates the incident reading beam and the reading beam reflected from the holographic disk. The polarizing beamsplitter PBS2 shall have, at the reading beam wavelength LR, a p-s intensity transmittance ratio of at least 1000 and s-p intensity reflectance ratio of at least 80. The dichroic beamsplitter DBS shall have a reflectance of at least 99 % for the tracking/addressing wavelength LT and a transmittance of at least 98 % for the reading wavelength LR. The combination of the polarizing beamsplitter PBS1 and quarter-wave plate separates the incident tracking/addressing optical beam and the tracking/addressing beam reflected from the holographic disk. The polarizing beamsplitter PBS1 shall have, at the tracking/addressing beam wavelength L T , a p-s intensity reflectance ratio of at least 100.
-6-
Reading laser
LR
Spatial light modulator
Data reading beam
Photodetector array
Data output
Polarizing beam splitter PBS2
Polarizing beam splitter PBS1 Dichroic beam splitter DBS
Tracking/addressing laser LT
Tracking/addressing beam Collimating lens
I1
Split photodetector Quarter wave plate
I1
I2
I2
Direction of pit tracks
Objective lens + d.c.-coupled amplifier K1
-
+
+ d.c.-coupled amplifier K2
Radial Addressing tracking signal signal
Holographic disk
L T : Wavelength of the tracking/addressing beam L R : Wavelength of the data reading beam I 1 , I 2 : Output currents from the split photodetector
Figure 1a – Optical system of the Reference Drive
-7-
9.2
Tracking and Addressing Channel The Tracking and Addressing Channel shall be used to generate tracking/addressing information and read manufacture Specific Disk Information (SDI).
9.2.1
T rackin g /ad d ressin g b eam The laser beam used for tracking/addressing shall have the following characteristics. + 10 nm
Wavelength
655 nm
Polarization
Circular
Focal length of objective lens
Such that to specifications
Numerical aperture
0,39 ± 0,01
- 5 nm
Light intensity at the rim of the pupil of the objective lens
conform
to
9.4.2
≥ 40% of the maximum intensity level in the radial direction, and ≥ 40% in the tangential direction
Wave front aberration from an ideal spherical wave front after passing through an ideal stack of disk layers 0,033 L rms max. Relative Intensity noise (RIN) 9.2.2
-126 dB/Hz max.
T rackin g /Add ressing /SDI sig n als The method of generating the axial tracking error is not specified for the Reference Drive. The radial tracking error signal shall be generated from the output currents of a split photodiode detector, the division of which runs parallel to the image of the pit tracks on the diode (see Figure 1a). The radial tracking error signal relates to the difference in the amount of light in the two halves of the exit pupil of the objective lens. The amplifier K 1 after the photodetector characteristics specified in Clause 18.
shall be d.c.-coupled with the bandwidth
The addressing information signal is generated from the reading signal issued from the sum of the output currents of the split photodiode detector. The addressing information reading signal relates to the total amount of light in the exit pupil of the objective lens. The amplifier K 2 after the photodetector shall be d.c.-coupled with the bandwidth characteristics specified in Clause 18. The SDI signal shall be derived from the reading of the content of tracking data area of specific tracks, as specified in Clause 18.
9.3
Data Holographic Reading Channel The Data Holographic Reading Channel shall be used to reconstitute the image from the stored hologram and read back the stored data.
9.3.1
Read in g b eam The pulsed laser beam used for data reading shall have the following characteristics. Wavelength
532 nm ± 0,1 nm
Polarization
Circular
Focal length of objective lens
5,000 mm ± 0,002 mm
Numerical aperture
0,50 ± 0,01
Light intensity at the rim of the pupil of the objective lens
O 55% of the maximum intensity level, in radial and tangential directions -8-
Wave front aberration from an ideal spherical wave front after passing through an ideal stack of disk layers 0,012 L rms max.
9.3.2
Coherent length
O 1,8 mm
Laser pulse width
< 50 ns at half maximum
Laser pulse energy
as specified in SDI (see Annex D)
Ref eren ce Pat t ern The reading beam shall be spatially modulated to generate the reading Reference Pattern light distribution shown on figure 1b. The spatial light modulator (see Figure 1a) could be a physical passive transmissive or reflective element. The content of the Reference Pattern in a plane perpendicular to the optical axis is specified versus a square pattern of 358x358 pixels with a pitch of 13,68 Qm ± 0,02 Qm and a fill factor of 85,2% ± 0,1 %. The Reference Pattern shall be constituted of 120 radial lines of On (illuminated) pixels. The size of the inner and outer diameters shall be 230 and 358 pixels. The width of the lines shall be 1 pixel. The modulation ratio of the On/Off (illuminated/non-illuminated) pixels of the Reference Pattern shall be at least 500.
Figure 1b – Reference Pattern used to recover the stored image of the Data Page
-9-
The relative positioning of the Reference Pattern versus the spindle axis and the optical axis shall be as shown on Figure 1c. The orientation axis of the Reference Pattern shall be disposed in direction of the spindle axis with a tolerance R better than ± 0,01°.
Figure 1c - Positioning of the Reference Pattern (Seen from the incoming beam side)
9.3.3
Ph o t o det ect or array The photodetector array shall be constituted of 576x576 elements that shall be used for the detection of data stored in the Data Page. The pitch of the elements shall be 12,0 Qm ± 0,5 Qm. The signal generated by each photodetector array element shall be linearly related to the energy received by this element during each reading pulse. Data detection shall be performed as specified in Annex H.2.
9.4 9.4.1
Conditions for measuring the operational signals T rackin g , Ad d ressin g , Sp ecif ic Disk Inf o rmatio n During the measurement of the signals, the focus of the tracking/addressing beam shall have an axial deviation of not more than e max (axial) = 0,23 Qm from the pit layer, and it shall have a radial deviation of not more than e max (radial) = 0,022 Qm from the centre of the track. - 10 -
9.4.2
Dat a read in g During data reading, the relative positioning of the centres of the focus of the data reading beam and the tracking/addressing beam shall be such that their axial distance shall be 100 Qm ± 1 Qm, and their radial and tangential misalignments shall be less than 0,1 Qm.
Normaliz ed serv o t ran sf er f u n ct io n s 9.4.3 9.4.3.1 Ref eren ce serv o f or axial t rackin g The reference servo for axial tracking used for measurement of servo related parameters specifications shall be as specified in 10.5.6. 9.4.3.2
9.4.4
Ref eren ce serv o f or rad ial t rackin g The reference servo for axial tracking used for measurement of servo related parameters specifications shall be as specified in 10.5.8. Ro t at io n o f t h e d isk The spindle shall position the disk as specified in 11.1. It shall rotate the disk at 300 rpm ± 30 rpm. The direction of rotation of the disk shall be counter-clockwise when viewed from the objective lens.
Section 2 - Mechanical and physical characteristics 10 10.1
Dimensional, mechanical, and physical characteristics of the disk General description of the disk The disk shall consist of a circular substrate with a hole in the centre, bearing a stack of layers incorporating the holographic storage layer (see Figure 2). The storage layer is protected from environmental influences by a laser-transparent protective cover layer. The centring of the disk on the drive spindle is performed on the edge of the centre hole of the substrate. Clamping is performed in the Clamping Zone (see Figure 3). Entrance surface Cover layer Holographic storage layer Gap layer 2 Dichroic mirror layer Gap Layer 1 Metadata layer Substrate
Figure 2 – Layers structure of the disk
- 11 -
10.2
Reference axis and plane of the disk Some dimensions of the disk are referred to a Disk Reference Plane D (see Figure 3). Plane D is defined by the perfectly flat annular surface of an ideal spindle onto which the Clamping Zone of the disk, on the entrance surface, is clamped, and which is normal to the axis of rotation of this spindle. The Reference Axis A of the disk passes through the centre of the centre hole of the disk, and is normal to Disk Reference Plane D. Reference Axis A Clamping Zone
D7 Reference Plane D
D9
Reference Plane D
Entrance surface
D8 D10 D6 Figure 3 – Disk dimensions
10.3
Dimensions of the disk The dimensions of the disk shall be measured in the operating environment. The outer diameter of the disk shall be (see Figure 3) D 6 = 120 mm ± 0,30 mm The centre hole shall have a diameter + 0,15 mm
D 7 = 15,00 mm
- 0,00 mm
There shall be no burr on the edges of the centre hole. The edge of the centre hole shall be rounded off or chamfered. The rounding radius shall be 0,1 mm max. The chamfer shall extend over a height of 0,1 mm max. The total thickness of the disk shall be 2,3 mm min. and 2,6 mm max.
10.4
Clamping Zone The Clamping Zone is the area on the entrance surface of the disk where the clamping mechanism of the drive grips the disk and is defined by D 8 and D 9 (see Figure 3). The clearance zone extending from the outer diameter of the Clamping Zone (D 8 ) to the inner diameter of the reflective zone (D 10 ) shall be excluded from the total thickness requirement; however there shall be no projection from the Disk Reference Plane D in the direction of the optical system of more than 0,2 mm in this zone. The outer diameter of the Clamping Zone shall be D 8 = 28 mm min. The inner diameter of the Clamping zone shall be D 9 = 22 mm max.
- 12 -
10.5
Mechanical characteristics All requirements in this clause shall be met in the operating environment.
10.5.1
M at erial The disk shall be made from any suitable materials such that it meets the requirements of this Ecma Standard.
10.5.2
M ass The mass of the disk shall not exceed 80 g.
10.5.3
M omen t o f in ert ia 2
The moment of inertia of the disk relative to axis A shall not exceed 0,160 g m . 10.5.4
Imb alan ce The imbalance of the disk relative to axis A shall not exceed 0,040 g m.
10.5.5
Axial d ef lect io n The axial deflection of the disk is measured as the axial deviation of the tracking/addressing pit layer. Thus it comprises the tolerances on the thicknesses of the crossed layers, on their indexes of refraction, and the deviation of the entrance surface from the Disk Reference Plane D. The deviation of any point of the tracking/addressing pit layer from its nominal position, in a direction normal to the Disk Reference Plane D, shall not exceed 0,3 mm in the Formatted Zone for rotational frequencies of the disk as specified in 9.4.4. The deviation shall be measured by the optical system defined in 9.1.
10.5.6
Axial accelerat io n The maximum allowed axial error e max (see Annex L) shall not exceed 0,23 µm, measured using the Reference Servo for axial tracking of the tracking/addressing layer. The rotational frequency of the disk shall be as specified in 9.4.4. The stationary part of the motor is assumed to be motionless (no external disturbances). The measurement shall be made using a servo with the transfer function 3i2 1+ V V0 1 0 H s (i- ) = × × i3 i1+ 3V 0
where - = 2Wf, V 0 /2W = 450 Hz, i = -1 or any other servo with 1 + H within the 20 % of 1 + Hs in the bandwidth of 5 Hz to 1 kHz. 2 Thus, the disk shall not require an acceleration of more than 0,38 m/s at low frequencies from the servo motor of the Reference Servo. 10.5.7
Rad ial ru n ou t The radial runout of the tracks in the tracking/addressing pit layer is measured as seen by the optical head of the Reference Drive. Thus it includes the distance between the axis of rotation of the spindle and reference axis A, the tolerances on the dimensions between axis A and the location of the track, and effects of non-uniformities in the index of refraction of the stack of layers.
The radial runout is the difference between the maximum and the minimum distance of any track from the axis of rotation, measured along a fixed radial line over one track. The radial runout shall not exceed 70 µm as measured by the optical system under conditions of a disk mounted on a perfect sized test fixture shaft, for rotational frequencies of the disk as specified in 9.4.4. 10.5.8
Rad ial accelerat io n The maximum allowed radial error e max (see Annex L) shall not exceed 0,022 µm, measured using the Reference Servo for radial tracking of the tracks. The rotational frequency of the disk shall be as specified in 9.4.4. The stationary part of the motor is assumed to be motionless (no external disturbances). - 13 -
The measurement shall be made using a servo with the transfer function 3i2 1+ V0 V0 1 H s (i- ) = × × i3 i1+ 3V 0
where - = 2W f , V 0 /2W = 650 Hz, i =
-1
or any other servo with 1 + H within the 20 % of 1 + H s in the bandwidth of 5 Hz to 2 1,0 kHz. Thus, the disk shall not require an acceleration of more than 0,08 m/s at low frequencies from the servo motor of the Reference Servo. 10.5.9
10.6
T ilt The tilt angle, defined as the angle that the normal to the entrance surface, averaged over a circular area of 1 mm diameter, makes with the normal to the Disk Reference Plane D, shall not exceed 0,80° in the radial direction and 0,30° in the tangential direction, in the Formatted Zone.
Optical characteristics
10.6.1
Substrat e The substrate has no optical requirement.
10.6.2
M et ad at a layer The Metadata layer shall be constituted of a reflective layer bearing data pits.
10.6.3
G ap layer 1 The thickness and index of refraction of Gap layer 1 at wavelength L T shall be such than within the Formatted Zone, the combined stack of layers specifications of 10.6.8 and 10.6.9 shall be met.
10.6.4
Dichro ic mirro r layer The reflectance of the dichroic mirror layer within the Formatted Zone, measured according to Annex A, shall be at least 80% at wavelength L R specified in 9.3.1.
10.6.5
G ap layer 2 The thickness, index of refraction and birefringence of Gap layer 2 at wavelengths L T and L R shall be such than within the Formatted Zone, the combined stack of layers specifications of 10.6.8 and 10.6.9 shall be met.
10.6.6
Ho lo g rap h ic st o rag e layer The holographic storage layer shall be used to store the Data Page holograms.
Its thickness, and index of refraction and birefringence shall be such than within the Formatted Zone, the combined stack of layers specifications of 10.6.8 and 10.6.9 shall be met. 10.6.7
Cov er layer The cover layer shall be used to protect the other layers.
Its thickness and index of refraction shall be such than within the Formatted Zone, the combined stack of layers specifications of 10.6.8 and 10.6.9 shall be met. 10.6.8
T h icknesses o f t h e st ack o f layers The thickness within the Formatted Zone of the stack "cover layer + holographic storage layer + Gap layer 2 + Dichroic mirror layer + Gap layer 1" shall be determined versus the average index of refraction N av at wavelength L T , as specified in Figure 4.
The thickness within the Formatted Zone of the stack "cover layer + holographic storage layer + Gap layer 2" shall be determined versus the average index of refraction N av at wavelength L R , as specified in Figure 5.
- 14 -
The average index N av of the stack of layers with individual thicknesses and indexes Ti and Ni shall be calculated as N av = Y Ni.Ti / YTi , with 1,45 Z Ni Z 1,65.
Figure 4 – Thickness of stack of layer between entrance surface and reflective pit Layer
Figure 5 – Thickness of stack of layers between entrance surface and dichroic mirror layer - 15 -
10.6.9
Birefrin gen ce of t h e st ack o f layers The birefringence of the layers within the Formatted Zone, measured according to Annex B, shall be less than: - 100 nm for the stack "cover layer + holographic storage layer + Gap layer 2 + Dichroic mirror layer + Gap layer 1" at wavelength L T , - 100 nm for the stack "cover layer + holographic storage layer + Gap layer 2" at wavelength L R .
11
Interface between disk and drive
11.1
Clamping method The drive spindle engages the disk by its centre hole. The disk is held against the spindle by an axial clamping force. The radial positioning of the disk is provided by the centring of the axis of the spindle in the centre hole of the disk. A turntable of the spindle shall support the disk in its Clamping Zone, determining the axial position of the disk in the case.
11.2
Tapered cone for disk clamping The device used for centring the disk for test measurements shall be a cone as defined in Annex C.
11.3
Clamping force The clamping force exerted by the spindle shall be less than 2,0 N ± 0,2 N.
Section 3 - Format of information 12
General description This section specifies:
13
-
the format of the tracking/addressing information and manufacture specific disk information contained in the pit layer,
-
the format of the data information stored in form of holograms in the storage layer.
Tracking and addressing information format / Specific Disk Information format The tracking and addressing information and manufacture Specific Disk Information shall be disposed along circular concentric tracks on the internal surface of the substrate and shall consist of successive depressions as seen from the entrance surface of the disk, called pits, in the otherwise flat reflective layer. The information shall be represented by variations of pit length and distance between pits. There shall be 20 172 pit tracks. + 0,2 mm The first pit track at the inside of the disk shall be located at radius 22,4 mm - 0,0 mm
13.1
Pit track pitch The pit track pitch shall be 1,6 Qm ± 0,1 Qm. The pit track pitch averaged over the Formatted Zone shall be 1,6 Qm ± 0,01 Qm.
- 16 -
13.2
Pit track format The pit track format is described hereafter in term of Channel bits. Each track shall contain 302 400 Channel bits. At the nominal test rotation speed of 300 rpm the nominal channel bit time period T shall be 661ns. The physical Channel bit length shall consequently vary with the track radius.
13.2.1
Sect o r The track (one revolution) shall be divided in 120 Sectors numbered from 0 to 119. The Sector layout shall be as shown in Figure 6.
Header
Sync
Tracking data
Land
Number of Channel bits per field 184
40
2288
8
Sector total Channel bits = 2520 Figure 6 – Sector format
13.2.2
Head er The header layout shall be as shown in Figure 7.
Address Mark
Address data
ECC
Reserved field
Number of Channel bits per field 48
64
32
40
Header total Channel bits = 184 Figure 7 – Header format
13.2.2.1 Add ress M ark The Address Mark shall consist of a pattern that does not occur elsewhere in the Sector. It shall have length of 48 Channel bits with the following pattern: 4T
4T
14T
4T
land pit Total: 48 Channel bits Figure 8 – Address Mark
- 17 -
4T
14T
4T
13.2.2.2 Address dat a The Address data format shall be as shown in Figure 9.
Control data
Track number H
Track number L
Sector number
Number of Channel bits per field 16
16
16
16
Address total Channel bits = 64
Figure 9 – Address data
The Control data bits shall be generated as shown in Figure 9.a. The track address of the first track at inner radius shall be –1 280. The track addresses of tracks located at radii larger than Track –1 280 shall be increased by 1 for each track.
Figure 9.a – Generation of Control data
- 18 -
The higher 16 bits, Track Number H, of Track Number data bits shall be generated as shown in Figure 9.b.
Figure 9.b – Generation of higher digits of Track Number data
The lower 16 bits, Track Number L, of Track Number data bits shall be generated as shown in Figure 9.c.
Figure 9.c – Generation of lower digits of Track Number data
- 19 -
The Sector Number data bits shall be generated as shown in Figure 9.d.
Figure 9.d – Generation of Sector Number data
13.2.2.3 ECC The ECC data format shall be as shown in Figure 10.
Control data ECC
Track number H ECC
Track number L ECC
Sector number ECC
8
8
8
8
Number of Channel bits per field ECC total Channel bits = 32
Figure 10 – ECC data
- 20 -
The higher digits of ECC data bits shall be generated as shown in Figure 10.a.
Figure 10.a – Generation of higher digits of ECC data
The lower digits of ECC data bits shall be generated as shown in Figure 10.b.
Figure 10.b – Generation of lower digits of ECC data - 21 -
13.2.2.4 Reserv ed f ield The reserved field shall be a blank space of 40 Channel bits length. The reserved field shall be ignored in interchange. 13.2.3
Sync This field shall have a 40 channel bits length and shall consist of a 3T/16T/16T/5T land/pit pattern, as shown on Figure 11.
3T
16T
16T
5T
land pit Total: 40 Channel bits Figure 11 – Sync field pattern
13.2.4
T rackin g dat a This field shall have a 2288 channel bits length and shall consist of a 4T land / 4T pit pattern, starting with a 4T land as shown on Figure 12.
4T
4T
4T
4T
4T 4T
4T
4T
land pit Total: 2 288 Channel bits Figure 12 – Tracking data pattern
13.2.5
13.3
Land Each Sector shall finish with a land field with a length of 8 Channel bits.
Specific Disk Information (SDI) The Specific Disk Information (SDI) shall be stored in the tracking data area of the Lead-in tracks of the pit layer, as specified in Annex D.
- 22 -
13.3.1
SDI byt es en co d ing The encoding of the SDI bytes shall be processed as shown on Figure 13.
Figure 13 – SDI bytes encoding
13.4
Radial alignment The misalignment [ of the Channel bits of adjacent tracks (see Figure 14) shall be less than ± 50 nm.
(n+1)th track nth track [ Figure 14 – Channel bit alignment
14
Data information format The data information shall be stored in the form of holograms in the volume of the storage layer. Each hologram shall contain a Data Page of information.
14.1
Data Page holograms layout in the storage layer All hologram layout format characteristics shall be specified in reference to the pit layer, as access to the information in the holographic storage layer is defined through the tracking/addressing features of the pit layer. The hologram track address shall be in particular designated by the corresponding pit track address.
14.1.1
Rad ial Dat a Pag e h o lo g ram p it ch The radial Data Page hologram pitch, the hologram track pitch, shall correspond to 8 pit track pitches.
- 23 -
14.1.2
Dat a Page ho lo gram layo u t w it h in t racks A track in the storage layer (one revolution of the disk) shall contain 840 Peapods (see Figure 15), each comprising a number of n holograms depending on the Zone, as specified in Clause 14.1.3.
Figure 15 – Peapods layout
14.1.3
Zones / T an g ent ial Dat a Pag e h o lo g ram p itch / Nu mber of Data Pag e h o lograms per Peap o d The holograms shall be exclusively stored in the tracking data area of the track. Within this area the tangential Data Page hologram pitch shall be the same in Zones defined in Table 1. This pitch shall vary from 8 to 4 Channel bit periods depending on the Zone. The centre of holograms shall coincide with passages to Zero of the Channel bit period signal. The centre of the first hologram in a track shall coincide with the third transition of the pit signal in the tracking data area (see Figure 16). The holograms shall be stored in sequential order so that to fill successively all positions 1 of the Peapods and then successively all positions 2 of the Peapods and then all position 3, \ etc. until all available positions in all Peapods have been used (see Figure 15). th
The number of holograms stored in the last (7 ) Peapod of each Sector (see Table 1) shall be reduced due to the smaller tracking data area space available for this Peapod at the end of each Sector.
- 24 -
Table 1 – Zones with different tangential Data Page hologram pitches Zone
Start pit track number
End pit track number
Number Start End Number of of pit address address hologram tracks tracks
Tangential hologram pitch
Holograms per Peapod
0
- 1 280
-1
1 280
(FB00)
(FFFF)
0
--
Peapods* 0,1, \ 5 7, 8, \12 \\\\. 833, 834, \ 838 --
1
0
1 279
1 280
(0000)
(04FF)
160
8
45
15
2
1 280
2 559
1 280
(0500)
(09FF)
160
8
45
15
3
2 560
3 839
1 280
(0A00)
(0EFF)
160
8
45
15
4
3 840
5 119
1 280
(0F00)
(13FF)
160
8
45
15
5
5 120
6 399
1 280
(1400)
(18FF)
160
8
45
15
6
6 400
7 679
1 280
(1900
(1DFF)
160
8
45
15
7
7 680
8 959
1 280
(1E00)
(22FF)
160
8
45
15
8
8 960
10 239
1 280
(2300)
(27FF)
160
8
45
15
9
10 240
11 519
1 280
(2800)
(2CFF)
160
8
45
15
10
11 520
12 799
1 280
(2D00
(31FF)
160
8
45
15
11
12 800
14 079
1 280
(3200)
(36FF)
160
8
45
15
12
14 080
15 359
1 280
(3700)
(3BFF)
160
8
45
15
13
15 360
16 639
1 280
(3C00)
(40FF)
160
4
90
30
14
16 640
17 919
1 280
(4100)
(45FF)
160
4
90
30
15
17 920
18 879
960
(4600)
(49BF)
120
4
90
30
16
18 880
18 891
12
(49C0)
(49CB)
2
4
90
30
(Number of Channel bit periods)
Peapods** 6, 13, .\ 839 --
NOTES: * First six Peapods of Sectors. ** Last seventh Peapods of Sectors.
Figure 16 – Position of the first Data Page hologram in a track
14.2 14.2.1
Data Page encoding User d at a The user data bytes shall be processed as shown on Figure 17 to generate the content of the Data Page of the hologram. Each 192 512 user data bytes shift shall be formatted in 188 packets of 1 024 bytes (see figure 18). - 25 -
These bytes shall be processed by addition of Header, Footer, Inter-Page ECC, Page number, Intra-Page ECC, scrambling to generate the content of the Data Page holograms.
Addition of Header and Footer
User data
Addition of Inter-Page ECC
Addition of Page number
Addition of Intra-Page ECC
Scrambling
Data Page content
Figure 17 – Data Page encoding
Figure 18 – Addition of Page number, Header and Footer
14.2.2
Header 28 bytes Header shall be added to each 1 024 user bytes packet (See Figures 17 and 18). These bytes shall be set to ZERO. They shall be ignored in interchange.
14.2.3
Foot er 16 bytes Footer shall be added to each 1 024 user bytes packet (See Figures 17 and 18). These bytes shall be set to ZERO. They shall be ignored in interchange.
14.2.4
ECC Error Correction Code (ECC) bytes are used by the error detection and correction system to rectify erroneous data in Data Pages.
14.2.4.1 Int er- Pag e ECC The 1 068 bytes of 188 user data packets constituted of Header + User data + Footer shall be processed by a Reed-Solomon code, as specified in Annex E1, to generate 20 packets of 1 068 Inter-Page ECC bytes, as shown on Figure 19.
- 26 -
15.2.4.2 Pag e n u mb er 4 bytes sequential Page numbers shall be added to each of the preceding (188+20) packets. Page number 0 shall be given to the first Page at inner diameter. Page numbers shall be incremented by one for each following Page. 14.2.4.3 In t ra- Pag e ECC The 1 072 bytes of each of the here above 208 packets shall be processed as specified in Annex E2 to generate 560 Intra-Page ECC bytes that shall be added to each of these 1 072 bytes to constitute the 1 632-bytes content of the Data Page, as shown on Figure 19.
Page number Page number \ \ Page number \ \ Page number
4 bytes 4 bytes \ \ \ \ 4 bytes \ \ \ \ 4 bytes
Page number \ Page number
4 bytes \ \ 4 bytes
Header + User data + Footer 0 Header + User data + Footer 1 \\ : \\ : Header + User data + Footer m \\ : \\ : Header + User data + Footer 187
Inter-Page ECC \\ Inter-Page ECC
0 : 19
1 068 bytes 1 068 bytes \ \ \ \ 1 068 bytes \ \ \ \ 1 068 bytes
1 068 bytes \ \ 1 068 bytes
: : : :
: : 8 bits/16 bits conversion through the look-up table
:
: :
Page number + Header + User data + Footer 0 Page number + Header + User data + Footer 1 \\ : Page number + Header + User data + Footer m \\ : Page number + Header + User data + Footer 187 Page number + Inter-Page ECC 0 \\ : Page number + Inter-Page ECC 19 Data before 8 to 16 bits conversion
1 072 bytes 1 072 bytes \ \ 1 072 bytes \ \ 1 072 bytes 1 072 bytes \ \ 1 072 bytes
Page number + Header +User data + Footer 0 Page number + Header + User data + Footer 1 \\ : \\ : Page number + Header + User data + Footer m \\ : \\ : Page number + Header + User data + Footer 187
2 144 bytes 2 144 bytes \ \ \ \ 2 144 bytes \ \ \ \ 2 144 bytes
:
Page number + Inter-Page ECC \\ Page number + Inter-Page ECC
0 : 19
2 144 bytes \ \ 2 144 bytes
: : : :
:
Intra-Page ECC Intra-Page ECC \\ Intra-Page ECC \\ Intra-Page ECC Intra-Page ECC \\ Intra-Page ECC
560 bytes 560 bytes \ \ 560 bytes \ \ 560 bytes 560 bytes \ \ 560 bytes
Intra-Page ECC Intra-Page ECC \\ \\ Intra-Page ECC \\ \\ Intra-Page ECC
560 bytes 560 bytes \ \ \ \ 560 bytes \ \ \ \ 560 bytes
Intra-Page ECC \\ Intra-Page ECC
560 bytes \ \ 560 bytes
Figure 19 – Inter-Page and Intra-Page ECC codes
14.2.5
Scramb lin g The 1 632-bytes Data Page content shall be scrambled by means of the circuit shown in Figure 20 which shall consist of a feedback bit shift register in which bits r 7 (msb) to r 0 (lsb) represent a scrambling byte at each 8-bit shift. The scrambling shall start at the beginning of each every 208 Pages, with pre-set values of positions r 14 to r 0 of the shift register as specified in figure 20.
Figure 20 – Feedback shift register for generating the scrambling bytes
14.3
Digital to image conversion
14.3.1. 8 bit s t o 16 b it s co n v ersion Each of the 1 632 bytes corresponding to the content of a page shall be transformed to 2x1 632 bytes by a 8 to 16 bits conversion using the look-up table shown on figure 21. This conversion shall be such that three 1's shall appear within each successive 16 bits. - 27 -
Each 1 632 obtained bytes shall represent the hologram content of a Data Page (see Figure 22).
Data (hex) 00 01 02 : : 80 81 82 : : FD FE FF 8 bits, 1 byte
B m, n 8 bits, 1 byte
15 14 13 12 11 10 9 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
7 6 5 4 3 0 0 0 1 1 0 0 1 0 0 0 0 1 0 1 : : 1 0 0 0 0 0 0 0 0 1 0 1 0 0 0 0 0 0 0 0 1 1 1 0 0 0 0 0 0 0 1 0 0 : : 0 0 0 1 0 0 0 0 1 0 0 0 0 0 1 0 0 1 0 0 0 0 0 0 0 1 0 1 0 0 0 0 0 16 bits, 2 bytes Three "1"s for each 16-bits (2-bytes) data
: : 0 0 0
0 0 0
1 1 1
0 0 0
: :
8 0 0 0
2 0 1 0
1 1 0 0
0 0 1 1
1 0 0
0 0 0
0 0 1
0 0 0
0 0 0
0 0 0
Digit
BB m, n 16 bits, 2 bytes
Look up table for 8 to 16 bits conversion
B 0, 0 B 0, 1 : B 0, n : B 0, 207
B 1, 0 B 1, 1 : B 1, n : B 1, 207
B 1 631, 0 B 1 631, 1 : B 1 631, n : B 1 631, 207
\ \ \ \
BB 0, 0 BB 1, 0 \ BB 0, 1 BB 1, 1 \ : : BB 0, n BB 1, n \ : : BB 0, 207 BB 1; 207 \
1 632 bytes
BB 1 631, 0 BB 1 631, 1 : BB 1 631, n : BB1 631, 207
1 632 x 2= 3 264 bytes
Figure 21 – 8 to 16 bits conversion
Data Page Data Page B B Data Page B B Data Page Data Page B Data Page
0 1 B B m B B 187 188 B 207
1 632 bytes 1 632 bytes B B B B 1 632 bytes B B B B 1 632 bytes 1 632 bytes B B 1 632 bytes
Page Coding : : : :
:
8 to 16 bits conversion Digital data Pixel image
: : : : : : : :
Figure 22 – Data Page image generation
14.3.2
Symb ol/Su b - Page After the 8 to 16 bits conversion, each 16 bits shall be represented in the Data Page by a 4X4 On/Offpixels Symbol, as illustrated on Figure 23, using the look-up table of Annex F. - 28 -
Bits to One shall correspond to On (illuminated)-pixels of the Data Page. Bits to Zero shall correspond to Off (non-illuminated)-pixels of the Data Page. 8 bit
16 bit
digits
Symbol
digits
0
1
2
3
4
5
6
7
8
9
10
11
7
6
5
4
3
2
1
0
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
12
13
14
15
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
0
1
0
□■□■ ■□□□ □□□□ □□□□
□□□□□□□□□□□■■□■□
0
0
0
:
:
:
:
0
1
0
0
1
0
0
0
0
0
0
0
0
: 0
0
1
0
1
0
0
□□□□□□□□■□□■□■□□
1
1
1
1
:
:
: 1
1
1
1
1
0
0
0
0
1
0
1
Off-pixel
: 1
:
On-pixel
□□■□ ■□□■ □□□□ □□□□ : :
0
0
0
0
0
0
0
0
■□□□□■□■□□□□□□□□
□□□□ □□□□ ■□■□ □□□■
See look-up table in Annex F
Figure 23 – Data Page pixel symbols representation after 8 to 16 bits conversion
A Sub-Page Sync Mark constituted of 16 On-pixels shall be added to 32 Symbols to constitute the Sub-Page image that shall be organized as shown on Figure 24.
Figure 24 – Pixel Symbols organization of the content of a Sub-Page - 29 -
A Page Sync Mark constituted of 16 On-pixels shall be added to 51 Sub-Pages to generate the Data Page image that shall be organized as shown on Figure 25.
Page Sync Mark = 16 centred On-pixels Sub-Page 1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
38
49
50
51
1 Page = 1 Page Sync Mark + 51 Sub-Pages = 1 632 Kbytes Figure 25 – Sub-Page organization of a Page
14.4
Data Page hologram - Reference Pattern The Data Page image generated as specified in 14.3.2 shall be stored as a hologram in the storage layer in relation with the Reference Pattern specified in 9.3.2.
15 15.1
Division of the Formatted Zone General description of the Formatted Zone The Formatted Zone specified in 14.1.3 contains all information on the disk relevant for data interchange. This information comprises tracking/addressing/SDI provisions, and stored data. In this clause the term "data" is reserved for the content of the Data Page, which, in general, is transferred to the host. Clause 15 defines the layout/content of the information. The characteristics of signals obtained from this information are specified in Sections 4 and 5.
15.2
Content/usage of the Formatted Zone The Formatted Zone shall be structured and used as shown in Table 2.
- 30 -
T able 2 – Content/us age of the F or m atted Z one Number of Number of pit tracks hologram tracks
Content / usage
Zone number(s)
Pit track addresses (Decimal)
Pit track addresses (Hexadecimal)
Lead-in Zone
0
-1 280 to -831
(FB00) to (FCC1)
450
\.
Buffer Zone 1
0
-830 to -511
(FCC2) to (FE01)
320
.\
Test Zone
0
-510 to -321
(FE02) to (FEBF)
190
\.
Buffer Zone 2
0
-320 to -1
(FEC0) to (FFFF)
320
\.
User data Zone
1 to 15
0 to 18 879
(0000) to (49BF)
18 880
2 360
Lead-out Zone
16
18 880 to 18 8911
(49C0) to (49CB)
12
2
15.2.1
Zon e 0 – L ead - in Z o n e / Bu f f er Z on e 1 / T est Z on e / Buf f er Z o n e 2 The Zone 0 shall be divided in 4 Sub-Zones.
15.2.1.1 L ead- in Z o ne The Lead-in Zone shall comprise 450 pit tracks. The Lead-in Zone shall be used for storing the SDI. 15.2.1.2 Bu f f er Z o n e 1 The Buffer Zone 1 shall comprise 320 pit tracks. 15.2.1.3 T est Z on e The Test Zone shall comprise 190 pit tracks. The Test Zone could be used for read tests. Its content is not specified by this Standard and shall be ignored in interchange. 15.2.1.4 Bu f f er Z o n e 2 The Buffer Zone 2 shall comprise 320 pit tracks. 15.2.2
Zon es 1 t o 15 - User d at a Z on e Zones 1 to 15 shall constitute the User data Zone used to store user data. The User data Zone shall comprise 18 880 pit tracks corresponding to 2360 hologram tracks that may contain 95 760 000 holograms storing 86 552 308 user Data Pages. The first user hologram on the disk shall be stored centred on pit Track 0.
15.2.3
Zon e 16 - L ead - o u t Z o n e The Lead-out Zone shall comprise 12 pit tracks corresponding to 2 hologram tracks. The Lead-out Zone shall be used to store the finalizing data specified in Annex G. The specified Data Page shall be stored repetitively in the two hologram tracks of the Lead-out Zone.
- 31 -
Section 4 - Characteristics of the tracking/addressing and SDI information 16
Method of testing The format of the pit tracking /addressing and SDI information on the disk is defined in Clause 13. Clause 17 specifies the requirements for the signals from the tracks, addresses and SDI, as obtained when using the Reference Drive specified in Clause 9.
16.1
Environment All signals specified in Clause 17 shall be within their specified ranges with the disk in any environment in the range of allowed operating environments defined in 8.1.1.
16.2
Use of the Reference Drive All signals specified in Clause 17 shall be measured in the indicated channel of the Reference Drive. The drive shall have the following characteristics for the purpose of these tests.
16.2.1
O ptics an d mech an ics The drive shall have a Tracking/Addressing Channel, with the implementation as given in 9.2. The tracking/addressing beam shall have the properties defined in 9.2.1. The disk shall rotate as specified in 9.4.4.
16.2.2
T rackin g /ad d ressin g b eam p ow er The tracking/addressing beam power shall be 0,5 mW ± 0,2 mW.
16.2.3
T rackin g req u iremen t s During the measurement of the signals, the focus of the beam shall follow the pit track with the requirements defined in Clause 9.4.1.
16.3
Definition of signals Figure 26 shows the signals specified in Clause 17. All signals are linearly related to currents I 1 and I 2 derived from the outputs of the split photodiode detector of the Reference Drive (see 9.1), and are therefore linearly related to the optical power falling on the detector. The reading signal I provided by the Addressing Channel is the high bandwidth sum signal I = I1 + I2 as processed by the band-pass filter described in Annex H1.
- 32 -
Beam on track in the tracking data field I1 + I2 (I 1 + I 2 ) max
(I 1 + I 2 ) min I1 – I2
0 Level
Figure 26a – Signals from the tracking data field
Figure 26b – Signal I = I1 + I2 in the different fields Figure 26 – Illustration of the various parameters for tracking/addressing signal characteristics
17 17.1
Signal requirements Reflectivity The reflectivity is defined as the ratio of the upper level of signal I = I 1 + I 2 obtained from a 4T mark to the signal I = I 1 + I 2 obtained from a totally reflecting disk. The reflectivity shall not be less than 18%.
17.2
Normalized Push Pull signal The push-pull signal is the sinusoidal difference signal (I 1 - I 2 ) in the Radial Tracking Channel, when the focus of the optical beam crosses the tracks. This signal can be used as error signal for radial tracking. The normalized peak-to-peak value of the push-pull signal shall meet the following requirement in the Formatted Zone: 0,4
(I 1 - I 2 ) PP
0,8
(I1 + I2) av
- 33 -
17.3
Modulation The modulation of signal I = I1 + I2 is the ratio of its average peak-to-peak value to its average top value. Modulation =
(I 1 + I 2 ) PP (I 1 + I 2 ) top av
The modulation shall not be less than 0,3 for the tracking data 4T marks.
17.4
Resolution The resolution I nT / I mT is the ratio of the average peak-to-peak value I nT of the signal obtained from nT pits and nT lands to the average peak-to-peak value of the signal I mT obtained from mT pits and mT lands. Resolution I nT / I mT =
InT PP av InT PP av
The resolution I 2T / I 4T shall not be less than 0,5 for the Address data or ECC 2T pits and tracking data 4T pits. The resolution I 16T / I 4T shall not be less than 0,5 for the Sync 16T pits and tracking data 4T pits.
17.5
4Ttop modulation The 4Ttop modulation is the ratio of the peak-to-peak variation value of the upper envelope of the signal obtained from 4T pits to its maximum upper level value. 4Ttop modulation =
(I4T top) PP (I4T top) max.
The 4T top modulation shall be less than 10% on a disk revolution.
17.6
Asymmetry The asymmetry (see Annex I) relates to the deviation of the centre levels of the signals of two distinct repeating pit and land patterns.
17.6.1
Asymmet ry ( 4T - 2T ) The asymmetry (4T - 2T) shall be less than ± 10% for the Address data or ECC 2T pits and tracking data 4T pits.
17.6.2
Asymmet ry ( 16T - 4T ) The asymmetry (16T - 4T) shall be less than ± 10% for the Sync 16T pits and tracking data 4T pits.
17.7
Jitter Jitter is the standard deviation (sigma) of the time variation of the digitized data. The jitter of the 4T pits and lands, measured as a percentage of the nominal pits and lands durations, shall be less than 8%.
17.8
Phase depth The phase depth of pits n×d LT
× 360°
where n is the index of refraction of the cover layer, d is the pit depth, and L T is the wavelength of the tracking/addressing laser, shall be less than 90°.
- 34 -
Section 5 - Characteristics of user data 18
User data – Method of testing Clauses 18 and 19 describe measurements to test conformance of the stored data on the disk with this Ecma Standard. It checks the legibility of stored data. The stored data is assumed to be arbitrary. The read tests shall be performed on the Reference Drive. The requirements in Clauses 18 and 19 define a minimum quality of the data, necessary for data interchange.
18.1
Environment All specifications of Clauses 19 and 20 shall be verified with the disk in any environment in the range of allowed operating environments defined in 8.1.1.
18.2
Reference Drive All specifications of Clauses 19 and 20 shall be measured in the Reference Drive. The drive shall have the following characteristics for the purpose of these tests:
18.2.1
O pt ics an d mech an ics The reference drive shall have Tracking/Addressing and Reading Channels as given in 9.2 and 9.3. The Reference Pattern used to read the data image shall be as specified in 9.3.2. The disk shall rotate as specified in 9.4.4.
18.2.2
T rackin g /ad d ressin g read in g p o w er The tracking/addressing reading power shall be 0,5 mW ± 0,2 mW.
18.2.3
Dat a read in g en ergy The data reading energy shall be as specified in the SDI (see Annex D).
18.2.4
T rackin g req u iremen t s During the measurement of the signals, the focus of the tracking/addressing beam shall follow the pit track with the requirements defined in 9.4.1.
18.2.5
Relat iv e p o sit io n in g o f t h e fo cu s o f t h e d at a read in g b eam and t he t rackin g /ad dressin g b eam During data reading, the relative positioning of the centres of the focus of the data reading beam and the tracking/addressing beam shall be as specified in Clause 9.4.2.
18.2.6
Dat a d et ect ion f o r t est in g p u rp oses Data shall be detected for testing purposes as specified in Annex H2.
19
Minimum quality of a Data Page This clause specifies the minimum quality of a Data Page as required for interchange of the data contained in that page. The quality shall be measured on the Reference Drive specified in 18.2. A byte error occurs when one or more bits in a byte have a wrong setting, as detected by ECC circuits. The stored data in a Data Page shall not contain any byte errors that cannot be corrected by the error correction circuit.
- 35 -
19.1
Reading energy damage Stored data shall not become damaged due to the repetitive reading of pages. Media shall be tested against reading energy damage. No error shall appear after ECC decoding after 1 million readouts.
20
Data interchange requirements A disk offered for interchange of data shall comply with the following requirements.
20.1
Tracking The focus of the optical beam shall not jump pit tracks unintentionally.
20.2
Stored data Data for interchange shall be stored anywhere within the User data Zone.
20.3
User-read data Any stored Page shall not contain byte errors during reading, after the error correction circuit.
- 36 -
Annex A (normative) Measurement of light reflectance A.1 Calibration method A good reference disk shall be chosen, for instance a glass disk with a golden reflective mirror. This reference disk shall be measured by a parallel beam as shown in Figure A.1
Rint Rs r
I
r
R
Figure A.1 - Reflectance calibration
In this figure the following applies. I = incident beam r = reflectance of the entrance surface R s = main reflectance of the measured reflective layer R int = other reflectance's of the entrance surface and of the measured reflective layer R // = measured value, using the arrangement of Figure A.1 R // = r + R s + R int r = ((n-1) / (n+1))
2
where n is the refraction index of the cover layer
R s = R // - r -R int 2
R s = [(1-r) × (R // - r)] / [1-r × (2 - R // )] The reference disk shall be measured on a reference drive and I mirror measured by the focused beam is equated to R s as determined above. Now the arrangement is calibrated and the focused reflectivity is a linear function of the reflectivity of the measured reflective layer, independently from the reflectivity of the entrance surface.
- 37 -
A.2 Measuring method The measuring method comprises the following steps. a) Measure the reflective light power D s from the reference disk with calibrated reflectivity R s b) Measure I XX in a defined area of the disk. c) Calculate the reflectivity as follows
R xx = Rs ×
Ixx Ds
- 38 -
Annex B (normative) Measurement of birefringence B.1 Principle of the measurement In order to measure the birefringence, circularly polarized light in a parallel beam is used. The phase retardation is measured by observing the ellipticity of the reflected light.
Figure B.1 - Ellipse with ellipticity e = b/a and orientation
The orientation
of the ellipse is determined by the orientation of the optical axis
= A – W/4
(I)
where A is the angle between the optical axis and the radial direction. The ellipticity e = b/a is a function of the phase retardation B e = tan [
1 W ( -B )] 2 2
(II)
When the phase retardation B is known the birefringence BR can be expressed as a fraction of the wavelength BR =
L B nm 2W
(III)
Thus, by observing the elliptically polarized light reflected from the disk, the birefringence can be measured and the orientation of the optical axis can be assessed as well.
B.2 Measurements conditions The measurement of the birefringence specified above shall be made under the following conditions: Mode of measurement in reflection
double pass through the specified stack of layers - 39 -
Wavelength L of the laser light
L T or L R nm ± 15 nm
Beam diameter (Full width half maximum)
1,0 mm ± 0,2 mm
Angle C of incidence in radial direction relative to the radial plane perpendicular to Reference Plane P
7,0° ± 0,2°
Clamping and chucking conditions
as specified in 11.2 and 11.3
Disk mounting
horizontally
Rotation
less than 1 Hz
Temperature and relative humidity
as specified in 8.1.1
B.3 Example of a measuring set-up Whilst this Ecma Standard does not prescribe a specific device for measuring birefringence, the device shown schematically in Figure B.2 as an example, is well suited for this measurement.
Figure B.2 - Example of a device for the measurement of birefringence -5
Light from a laser source, collimated into a polarizer (extinction ratio 10 ), is made circular by a L/4 plate. The ellipticity of the reflected light is analyzed by a rotating analyzer and a photo detector. For every location on the disk, the minimum and the maximum values of the intensity I are measured. The ellipticity can then be calculated as 2
e = I min / I max
(IV)
BR = L /4 - L/W × arctang
II
Combining equations II, III and IV yields min
max
This device can be easily calibrated as follows I min is set to 0 by measuring a polarizer or a L/4 plate , I min = I max when measuring a mirror.
- 40 -
Apart of the d.c. contribution of the front surface reflection, a.c. components may occur, due to the interference of the reflection(s) of the front surface with the reflection(s) from the internal layers. These a.c. reflectance effects are significant only if the disk substrate has an extremely accurate flatness and if the light source has a high coherence.
- 41 -
- 42 -
Annex C (normative) Tapered cone for disk clamping The device used for centring the disk for measurement shall be a cone with a taper angle c = 40,0°± 0,5° (see Figure C.1).
Entrance surface
c
Figure C.1 - Tapered cone
- 43 -
- 44 -
Annex D (normative) Specific Disk Information The Specific Disk Information (SDI) recorded in the tracking data area of the Lead-in tracks shall contain the items/parameters listed in Table D.1. Format, number of bytes and position in the tracks of each item/parameter shall be as specified in the table. T able D.1 – SDI c ontent Pit Track number Pit Sector numberStart Channel bit * DEC -1 280
-1 279
: -1 231
-1 230 : -1 181 -1 180 : -1 131
HEX FB00
FB01
: FB31
FB32 : FB63 FB64 : FB95
DEC 0
HEX 00
1
01
2
02
: 199
: C7
0
00
1
01
2
02
: 199
: C7
: 0
: 00
1
01
2
02
: 199
: C7
DEC 224 256 288 320 352 384 608 640 656 2 512 224 2 512 224 2 512 : 224 2 512 224 656 2 512 224 2 512 224 2 512 : 224 2 512 : 224 656 2 512 224 2 512 224 2 512 : 224 2 512
Items
Format / Meaning Bytes
HEX 00E0 Version of disk format 2 / HVD-ROM 100 GB 2 0100 Version of Specific Disk Information (SDI)n / (Version n) x 100 2 0120 Disk category 2 / HVD-ROM 2 0140 Disk size 1 / 120 mm 2 0160 Disk capacity n / n Gbytes 2 0180 Reserved Set to Zero 14 0260 Hologram read energy n / n nanoJoules 2 0280 Write strategy 1 / Sequential 1 0290 Reserved Set to Zero 116 09D0 00E0 Reserved Set to Zero 143 09D0 00E0 Reserved Set to Zero 143 09D0 : : : : 00E0 Reserved Set to Zero 143 09D0 Repeat of Channel bits 224 to 655 27 00E0 0290 Reserved Set to Zero 116 09D0 00E0 Reserved Set to Zero 143 09D0 00E0 Reserved Set to Zero 143 09D0 : : : : : 00E0 Reserved Set to Zero 143 09D0 : : : : : Repeat of Channel bits 224 to 655 27 00E0 0290 Reserved Set to Zero 116 09D0 : 00E0 Reserved Set to Zero 143 09D0 : 00E0 Reserved Set to Zero 143 09D0 : : : : : 00E0 Reserved Set to Zero 143 09D0 Repeat of tracks -1 280 to -1 231
Repeat of tracks -1 280 to -1 231
* NOTE: The Channel bits of each Sector are numbered from 1 to 2 520.
- 45 -
- 46 -
Annex E (normative) ECC The codes used to generate the Inter-Page and Intra-Page ECC bytes shall be as specified in this annex.
E.1 Inter- Page ECC The 1 068 bytes of the 188 packets described in Clause 14.2.4.1 shall be processed by a ReedSolomon code (255,235,20) to generate 20 packets of 1 068 Inter-Page ECC bytes, as shown on figure E.1. Header + User data + Footer = 1 068 bytes B 0, 0
B 1, 0
B m, 0
B 1 067, 0
188 packets
B 0, 187
B m, 187
B 1 067, 187
Reed-Solomon code (255, 235, 20)
B 0, 188
B m, 188
B 1 067, 188
B 0, 207
B m, 207
B 1 067, 207
Inter-Page ECC = 1 068 bytes
Figure E.1 – Generation of the Inter-Page ECC bytes
- 47 -
20 packets
E.2 Intra-Page ECC The 1 072 bytes packets of Clause 14.2.4.1 corresponding to User data + Inter-Page ECC bytes shall be first converted in 2 144 bytes packets through the 8 to 16 bits conversion table shown in Figure E.2.
B m, n 8 bits, 1 byte
Data (hex)
15 14 13 12 11 10 9
8
00 01 02 : : 80 81 82 : : FD FE FF 8 bits, 1 byte
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
1 1 1
0 0 0
: :
: :
3
2
1
0 Digit
0 0 0 1 1 0 0 1 0 0 0 0 1 0 1 : : 0 0 1 0 1 0 0 0 0 0 0 0 0 1 0 1 0 0 0 0 0 1 0 0 1 0 1 0 0 0 0 1 0 : : 0 0 0 1 0 0 0 0 1 0 0 0 0 0 1 0 0 1 0 0 0 0 0 0 0 1 0 1 0 0 0 0 0 16 bits, 2 bytes Three "1"s for each 16-bits (2-bytes) data
0 1 0
1 0 0
0 1 1
1 0 0
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
0 0 0
7
6
5
4
BB m,n 16 bits, 2 bytes
Look-up table for 8 to 16 bits conversion
B 0, 0 B 0, 1 : B 0, n : B 0, 207
B 1, 0 B 1, 1 : B 1, n : B 1, 207
\ \ \ \
B 1 071, 0 B 1 071, 1 : B 1 071, n : B 1 071, 207
1 072 bytes
BB 0, 0 BB 0, 1
BB 1, 0 BB 1, 1
\ \
BB 1 071, 0 BB 1 071, 1
BB 0, n : BB 0, 207
BB 1, n : BB 1, 207
\
BB 1 071, n : BB 1 071, 207
\
1 072 x 2 = 2 144 bytes
Figure E.2 – 8 to 16 bits conversion
These 2 144 bytes packets shall be then processed by the ECC/LDPC encoding of figure E.3a, E.3b and E.3c to generate 560 Intra-Page ECC bytes added to each of the initial 1 072 bytes packets. 1 072 x 2 =
2 144 BB m, n
BB 0, n
BB 1, n
\
C0 134 x 2 = 268 bytes 1 072 x 2 = 2 144 bits
C1 134 x 2 = 268 bytes 1 072 x 2 = 2 144 bits
C2 134 x 2 = 268 bytes 1 072 x 2 = 2 144 bits
D0
D1
D2
bytes \
BB1 071, n
2 144 bytes = 2 144bits x 8 C3 C4 C5 134 x 2 134 x 2 134 x 2 = 268 = 268 = 268 bytes bytes bytes 1 072 x 2 1 072 x 2 1 072 x 2 = 2 144 = 2 144 = 2 144 bits bits bits
Ck \
Di
\
C6 134 x 2 = 268 bytes 1 072 x 2 = 2 144 bits
D 2 143
C7 134 x 2 = 268 bytes 1 072 x 2 = 2 144 bits
Q0 560 bits 70 bytes
B 0, n
Header + User Data + Footer B 1, n \
B m, n
1 072 bytes \ B 1 071, n
Qk R0 R1 \ R 559 LDPC redundancy 560bits
Intra-Page ECC construction
Q1 560 bits 70 bytes
Intra-Page ECC 560 bytes B 1 072, n \ B 1 631, n
Figure E.3a – Generation of the Intra-Page ECC bytes - 48 -
Q2 Q3 Q4 Q5 Q6 560 560 560 560 560 bits bits bits bits bits 70 70 70 70 70 bytes bytes bytes bytes bytes 560 bits x 8 = 560 bytes Intra-Page ECC (LDPC redundancy)
Q7 560 bits 70 bytes
H
=
I I I I I I I
I
80 bits
I
1x1
2x1
1x2
2x2
1x3
2x3
1x4
2x4
1x5
2x5
1x6
2x6
80 bits
80 bits
I
B B 3x2 B 3x3 B 3x4 B 3x5 B 3x6 B
B B B B B B B
B B B B B B B
80 bits
\ \
\ \
3x1
\ \
I
I'
25x1
)' 26x2 )' 26x3 )' 26x4 )' 26x5 )' 26x6 )'
I 0 0 0 0 0 0
0 I 0 0 0 0 0
0 0 I 0 0 0 0
0 0 0 I 0 0 0
0 0 0 0 I 0 0
0 0 0 0 0 I 0
0 0 0 0 0 0 I
64 bits
80 bits
80 bits
80 bits
80 bits
80 bits
80 bits
80 bits
=
1 0 0 0 : : : : 0
0 1 0 0 : : : : 0
0 0 1 0 : : : : 0
26x1
( ( ( ( ( (
25x2 25x3 25x4 25x5 25x6
80 bits
80 bits 80 bits 80 bits 560 bits
80 bits
Width
80 bits 80 bits 80 bits
2704 bits Length
=
0 0 0 : : : : 0 1
1 0 0 : : : : 0 0
0 1 0 : : : : 0 0
0 0 1 .
0 0 0 . .
\
\
\ \ \ . . .
\ \ \
\
\
\ \ \
. . .
0 0 0 : : : 0 1 0
. . . \
I'
80 bits
80 bits
\ . . .
\
\
. . .
\
0 : : : 0 1 0 : 0
64 bits 80 bits
64 bits
Figure E.3b – Intra-Page ECC code structure
0
\
\
\ \
Rj
Initial value H 0, j
H
=
H 1, j
H 2, j
x
x
x
D0
D1
D2
\\\
\\\
\
\
x
H 2 142, j \ \
Di
D0
D1
D2
H 0, 0
H 1, 0
H 2, 0
\
H i, 0
\
H 2 143, 0
\
H 2 703, 0
H 0, 1
H 1, 1
H 2, 1
\
H i, 1
\
H 2 143, 1
\
H 2 703, 1
H 0, 2
H 1, 2
H 2, 2
\
H i, 2
\
H 2 143, 2
\
H 2 703, 2
:
:
:
:
:
:
:
:
:
H 0, j
H 1, j
H 2, j
\
H i, j
\
H 2 143, j
\
H 2 703, j
:
:
:
:
:
:
:
:
\
H i, 559
\
H 0, 559 H 1, 559 H 2, 559
Di
H i, j
D 2 143
H 2 143, j
x
x
D 2 142
D 2 143
R0 R1 R2 \ Rj \
H 2 143, 559 \
: H 2 703, 559
Figure E.3c – Intra-Page ECC code structure
- 49 -
R 559
For I = 0: 2 143 Rj = (Rj) xor (Hij and Di) End
- 50 -
Annex F (normative) 16 bits to Symbols conversion look-up table The conversion of the 16-bits data in Symbols and Symbols to 16-bits data shall be done as shown in Table F.1. Bits to One shall correspond to ON (illuminated) pixels. Bits to Zero shall correspond to Off (non-illuminated) pixels.
- 51 -
T able F .1 – 16- bits data to Sym bols c onvers ion
- 52 -
T able F .1 – 16- bits data to Sym bols c onvers ion
- 53 -
T able F .1 – 16- bits data to Sym bols c onvers ion
- 54 -
T able F .1 – 16- bits data to Sym bols c onvers ion
- 55 -
T able F .1 – 16- bits data to Sym bols c onvers ion
- 56 -
T able F .1 – 16- bits data to Sym bols c onvers ion
- 57 -
T able F .1 – 16- bits data to Sym bols c onvers ion
- 58 -
T able F .1 – 16- bits data to Sym bols c onvers ion
- 59 -
T able F .1 – 16- bits data to Sym bols c onvers ion
- 60 -
T able F .1 – 16- bits data to Sym bols c onvers ion
- 61 -
T able F .1 – 16- bits data to Sym bols c onvers ion
- 62 -
T able F .1 – 16- bits data to Sym bols c onvers ion
- 63 -
T able F .1 – 16- bits data to Sym bols c onvers ion
- 64 -
T able F .1 – 16- bits data to Sym bols c onvers ion
- 65 -
- 66 -
Annex G (normative) Finalizing data The Finalizing data shall be as shown in Table G.1. The 41 finalizing bytes shall be stored at the beginning of a Data Page filled with additional bytes containing Zero data. T able G .1 – Finalizing data Item
Format/ Meaning
Bytes
Version of disk format
2 / HVD-ROM 100 GB
2
Version of Specific Disk Information
n / Version number x 100
2
Disk category
2 / HVD-ROM
2
Disk size
1 / 120 mm
2
Disk capacity
n / n Gbytes
2
Reserved
Set to Zero
14
Hologram read energy
n / n nanoJoules
2
Write strategy
1 / Sequential
1
Reserved
Set to Zero
2
Start track of user data
n / Track address number
2
Start Sector of user data
n / Sector address number
1
Start Channel bit of user data
n / Channel bit number
2
End track of user data
n / Track address number
2
End Sector of user data
n / Sector address number
1
End Channel bit of user data
n / Channel bit number
2
Amount of stored data
n / n Gbytes
2
- 67 -
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Annex H (normative) Tracking/Addressing and Data Reading Channels characteristics
H.1 Tracking/Addressing Channel characteristics Analog signals and jitter shall be measured in the Tracking/Addressing Channel using the following circuit:
Jitter test points
Analog test point From reading
Band-pass
amplifier K 1
filter
Comparator
Edge detector
Leading edge Trailing edge
Figure H.1 – Addressing Channel block diagram
The band-pass filter shall be of the 2nd Order Bessel type with a bandwidth frequency of 20 Hz to 2 MHz.
H.2 Data Reading Channel characteristics Data shall be detected in the Data Reading Channel by the following circuit:
Photodetector array Current/voltage converter
Analog/digital converter
Decoder
Data
Figure H.2 – Data Reading Channel block diagram
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H.2.1 Sync Marks detection The Data Page Sync Mark shall be detected, as shown on Figure H.3a, by calculating the sum of the intensity of 12x12 (-6 to +6) pixels square for different positions of centre of this square in a range of 40x40 (-20 to +20) pixels around its supposed nominal position. The position of the Data Page Sync Mark corresponds to the maximum of the detected sum.
S(x+x’, y+y’) is the pixel signal intensity on the photodetector array.
Figure H.3a – Example of detection process of the Data Page Sync Mark
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The Sub-Page Sync Mark shall be detected, as shown on Figure H.3b, by calculating the sum of the intensity of 12x12 (-6 to +6) pixels square for different positions of centre of this square in a range of 40x40 (-20 to +20) pixels around its supposed nominal position The position of the Sync Mark corresponds to the maximum of the detected sum.
Figure H.3b – Example of detection process of the Sub-Page Sync Mark
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H.2.2 Symbol decoding The Symbol decoding shall be performed by a correlation process, as shown on Figure H.4. The data content of the Symbol shall be the data content of the filter Fi(x,y) giving the maximum of the multiplication signal Ci.
Figure H.4 – Symbol decoding
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Annex I (normative) Asymmetry measuring definition The asymmetry of signals from mT and nT pits and lands shall be measured based on the following definitions. See Figure I.1.
mT pits and lands
nT pits and lands
mT pits and lands
IH
IL
I L bot
I L top
I H bot
I H top
0 Level
Figure I.1 – Signal from tracking/addressing data with mT and nT pits and lands
Asymmetry (mT-nT) =
1/2 [(I L top + I L bot ) - (I H top + I H bot )] I L top - I L bot
where I L and I H are the peak-to-peak values of the Tracking/Addressing Channel signals for mT and nT pits and lands, read under the conditions specified in 16.2. I L top , I H top , I L bot , I H bot are the top and bottom levels of I L and I H .
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Annex J (informative) Office environment
J.1 Air cleanliness Due to their construction and mode of operation, Holographic Disk Cartridges have considerable resistance to the effects of dust particles around and inside the disk drive. Consequently, it is not generally necessary to take special precautions to maintain a sufficiently low concentration of dust particles. Operation in heavy concentrations of dust should be avoided, e.g. in a machine shop or on a building site. Office environment implies an environment in which personnel may spend a full working day without protection and without suffering temporary or permanent discomfort.
J.2 Effects of operation In the office environment (as well as other environments) it is possible for a holographic disk drive to degrade the quality of the stored pixels if the reading energy is applied to a track for a long period of time. The media manufacturer’s selection of the value for the maximum reading energy allowed in the User data Zones, as well as the drive manufacturer’s reading energy management method, should reflect this possibility and be designed to minimize any risk to data integrity.
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Annex K (informative) Transportation
K.1 General As transportation occurs under a wide range of temperature and humidity variations, for different periods, by many methods of transport and in all parts of the world it is not possible to specify conditions for transportation or for packaging. The following gives recommendations.
K.2 Packaging The form of packaging should be agreed between sender and recipient or, in the absence of such agreement, is the responsibility of the sender. It should take account of the following hazards.
K.2.1 Temperature and humidity Insulation and wrapping should be designed to maintain the following conditions during transportation. Temperature
5°C to 32°C
Atmospheric pressure
60 kPa to 106 kPa
Relative Humidity
5% to 80%
Absolute air humidity
25g/m max.
3
No condensation on the disk.
K.2.2 Impact loads and vibration Avoid mechanical loads that would distort the shape of the disk. Avoid dropping the disk. Disks should be packed in a rigid box containing adequate shock absorbent material. The final box should have a clean interior and a construction that provides sealing to prevent the ingress of dirt and moisture.
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Annex L (informative) Track deviation measurement The deviation of a track from its nominal location is measured in the same way as a drive sees a track, i.e. through a tracking servo. The strength of the Reference Servo used for the test is in general less that the strength of the same servo in a normal drive. The difference in strength is intended for margins in the drive. The deviation of the track is related to the tracking error between the track and the focus of the optical beam, remaining after the Reference Servo. The tracking error directly influences the performance of the drive, and is the best criterion for testing track deviations. The specification of the axial and radial deviations can be described in the same terms. Therefore, this annex applies to both axial and radial track deviations.
L.1 Relation between requirements The acceleration required by the motor of the tracking servo to make the focus of the optical beam follow the tracks on the disk (see 11.5.6 and 11.5.8) is a measure for the allowed deviations of the tracks. An additional measure is the allowed tracking error between the focus and the track (see 18.2.4). The relation between both is given in Figure L.1 where the maximum allowed amplitude of a sinusoidal track deviation is given as a function of the frequency of the deviation. It is assumed in the figure that there is only one sinusoidal deviation present at a time.
log (x
max )
e
max
log(f )
94-0145-A
Figure L.1 - Maximum allowed amplitude of a single, sinusoidal track deviation
At low frequencies the maximum allowed amplitude x max is given by 2
x max = a max / (2Wf) ,
(1)
where a max is the maximum acceleration of the servo motor.
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At high frequencies the maximum allowed amplitude x max is given by x max = e max
(2)
where e max is the maximum allowed tracking error. The connection between both frequency regions is given in L.3.
L.2 Reference Servo The above restrictions of the track deviations are equal to the restriction of the track deviations for a Reference Servo. A Reference Servo has a well-defined transfer function, and reduces a single, sinusoidal track deviation with amplitude x max to a tracking error e max as in Figure L.1. The open-loop transfer function of the Reference Servo shall be
H s (i- ) =
V0 1 × c i-
2
i-c V0 × i1+ cV 0 1+
(3)
where i = -1 , - = 2Wf and V 0 = 2Wf 0 , with f 0 the 0 dB frequency of the open-loop transfer function. The constant c gives the cross-over frequencies of the lead-lag network of the servo: the lead break f0 frequency f1 = and the lag break frequency f2 = f0 × c . The reduction of a track deviation x to a c tracking error e by the Reference Servo is given by e 1 = x 1+ H s
(4)
If the 0 dB frequency is specified as V0 =
amax c emax
(5)
then a low-frequency track deviation with an acceleration a max will be reduced to a tracking error e max, and a high frequency track deviation will not be reduced. The curve in Figure L.1 is given by
x max = e max 1 + H s
(6)
The maximum acceleration required from the motor of this Reference Servo is 2
a max (motor) = e max - 1 + H s
(7)
At low frequencies f > f 0 / c applies
a max (motor) = a max (track) =
V 0 2emax
(8)
c
Hence, it is permitted to use a max(motor) as specified for low frequencies in 10.5.6 and 10.5.8 for the calculation of V 0 of a Reference Servo.
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L.3 Requirement for track deviations The track deviations shall be such that, when tracking with a Reference Servo on a disk rotating at the specified frequency, the tracking error shall not be larger than e max during more than 10 Qs. The open-loop transfer function of the Reference Servo for axial and radial tracking shall be given by equation (3) within an accuracy such that |1 + H| does not differ by more than ± 20% from its nominal value in a bandwidth from 20 Hz to 150 kHz. The constant c shall be 3. The 0 dB frequency V0 shall be given by equation (5), where a max and e max for axial and radial tracking are specified 2W in 9.4.1 and 18.2.4.
L.4 Measurement implementation Three possible implementations for axial or radial measurement systems have been given below. H a is the open-loop transfer function of the actual tracking servo of the drive. H s is the transfer function for the Reference Servo as given in equation (3). x and y are the position of the track and the focus of the optical beam. e s is the tracking error after a Reference Servo, the signal of which has to be checked according to the previous paragraph.
Position sensor + y
Servo
x
+
Filter 1 1 + HS
es
ea
94-0081-B
L.2 - Implementation of a Reference Servo by filtering the track position signal with the reduction characteristics of the Reference Servo
es +
x
Hs
Ha
Ha
-
y
94-0082-B
Figure L.3 - Implementation of a Reference Servo by changing the transfer function of the actual servo
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ea
+
x
1+ Ha 1+ Hs Ha
es
y
-
94-0083-B
Figure L.4 - Implementation of a Reference Servo by changing the tracking error of the actual servo
The optimum implementation depends on the characteristics H a and H s . Good results for motors in leaf springs are often obtained by using separate circuits in a low and high frequency channel. The implementation of Figure L.2 is used in the low-frequency channel, while that of Figures L.3 or L.4 is used in the high-frequency channel. The signals from both channels are added with a reversed cross-over filter to get the required tracking error. In the low-frequency channel one can also use the current through the motor as a measure of the acceleration of the motor, provided the latter is free from hysteresis. The current must be corrected for the transfer function of the motor and then e e derived from = be converted to a tracking error with a filter with a transfer function a x- 2 equation (4).
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