1、INTERNATIONAL STANDARD lSO/IEC 10090 First edition 1992-l O-l 5 Information technology - 90 mm optical disk cartridges, rewritable and read only, for data interchange Technologies de Iinformation - Car-touches pour disques optiques de diametre 90 mm, r - the mechanical and physical characteristics o
2、f the cartridge, so as to provide mechanical interchangeability between data processing systems; - the format of the information on the disk, both embossed and user-written; - the characteristics of the embossed information on the disk; - the magneto-optical characteristics of the disk, enabling pro
3、cessing systems to write data onto the disk; - the minimum quality of user-written data on the disk, enabling data processing systems to read data from the disk. 2 Conformance A 90 mm optical disk cartridge is in conformance with this International Standard if it meets all mandatory requirements spe
4、cified herein. Annex R specifies the zones of the disk in which the requirements for the signal characteristics given in the body of this International Standard shall be met, and the zones in which a relaxation of these requirements is permitted. A drive claiming conformance with this International
5、Standard shall be able, in the operating environment, to write on any optical disk cartridge which is in conformance with this International Standard, and to read from any optical disk cartridge which is in conformance with this International Standard. A drive shall not claim conformance if it canno
6、t accept the full range of media conforming to this International Standard but only a specific sub-set of it. 3 Normative reference The following standard contains provisions which, through reference in this text, constitute provisions of this International Standard. At the time of publication, the
7、edition indicated was valid. All standards are subject to revision, and parties to agreements based on this International Standard are encouraged to investigate the possibility of applying the most recent edition of the standard listed below. Members of EC and IS0 maintain registers of currently val
8、id International Standards. IEC 950: 1991, Safety of information technology equipment, including electrical business equipment. 4 Definitions For the purpose of this International Standard the following definitions apply. 4.1 case: The housing for an optical disk, that protects the disk and facilita
9、tes disk interchange. 1 ISO/IEC 10090:1992 (E) 4.2 cyclic redundancy check (CRC): A method for detecting errors in data. 4.3 embossed mark: A mark so formed as to be unalterable by magneto-optical means. 4.4 entrance surface: The surface of the disk on to which the optical beam first impinges. 4.5 e
10、rror correction code (ECC): An error-detecting code designed to correct certain kinds of errors in data. 4.6 field: A subdivision of a sector. 4.7 format: The arrangement or layout of information on the disk. 4.8 groove: See 4.11. 4.9 interleaving: The process of allocating the physical sequence of
11、units of data so as to render the data more immune to burst errors 4.10 Kerr rotation: The rotation of the plane of polarization of an optical beam upon reflection from the recording layer, as caused by the magneto-optical effect. 4.11 land and groove: A trench-like feature of the disk, applied befo
12、re the recording of any information, and used to define the track location. The groove is located nearer to the entrance surface than the land with which it is paired to form a track. 4.12 mark: A feature of the recording layer which may take the form of a magnetic domain, a pit, or any other type o
13、r form that can be sensed by the optical system. The pattern of marks represents the data on the disk. Note 1 - Subdivisions of a sector which are named mark are not marks in the sense of this definition. 4.13 optical disk: A disk that will accept and retain information in the form of marks in a rec
14、ording layer, that can be read with an optical beam. 4.14 optical disk cartridge (ODC): A device consisting of a case containing an optical disk. 4.15 polarization: The direction of polarization of an optical beam is the direction of the electric vector of the beam. Note 2 - The plane of polarizatio
15、n is the plane containing the electric vector and the direction of propagation of the beam. The polarization is right-handed when to an observer looking in the direction of propagation of the beam, the end-point of the electric vector would appear to describe an ellipse in the clockwise sense. 4.16
16、recording layer: A layer of the disk on, or in, which data is written during manufacture and/or use. 4.17 Reed-Solomon code: An error detection and/or correction code which is particularly suited to the correction of errors which occur in bursts or are strongly correlated. 4.18 rewritable optical di
17、sk: An optical disk in which data in specified areas can be written, erased and rewritten by an optical beam. 4.19 sector: The smallest addressable part of a track in the Information Zone of a disk that can be accessed independently of other addressable parts of the zone. 4.20 substrate: A transpare
18、nt layer of the disk, provided for mechanical support of the recording layer, through which the optical beam accesses the recording layer. 4.21 track: The path which is to be followed by the focus of the optical beam during one revolution of the disk. 4.22 zone: An annular area of the disk. 2 ISO/IE
19、C 10090:1992 (E) 5 Conventions and notations 5.1 Representation of numbers - A measured value is rounded off to the least significant digit of the corresponding specified value. It implies that a specified value of 1.26 with a positive tolerance of + O,Ol, and a negative tolerance of -0,02 allows a
20、range of measured values from 1,235 to 1,275. - Letters and digits in parentheses represent numbers in hexadecimal notation. - The setting of a bit is denoted by ZERO or ONE. - Numbers in binary notation and bit combinations are represented by strings of ZEROS and ONES. - Numbers in binary notation
21、and bit combinations are shown with the most significant bit to the left. - Negative values of numbers in binary notation are given in TWOs complement. - In each field the data is recorded so that the most significant byte (byte 0) is recorded first. Within each byte the least significant bit is num
22、bered 0 and is recorded last, the most significant bit (numbered 7 in an 8-bit byte) is recorded first. This order of recording applies also to the data input of the Error Detection and Correction circuits and to their output. 5.2 Names The names of entities, e.g. specific tracks, fields, etc., are
23、given with a capital initial. 6 List of acronyms AM ccs CRC DDS DMA ECC FAl FA2 ID LSB MSB ODC ODF PA PDL RWZ7) SDL SM Address Mark Continuous Composite Servo (tracking method) Cyclic Redundancy Check Disk Definition Sector Defect Management Area Error Correction Code Functional Area 1 Functional Ar
24、ea 2 Identifier Least Significant Byte Most Significant Byte Optical Disk Cartridge Offset Detection Field Postamble Primary Defect List Run Length Limited (code) Secondary Defect List Sector Mark Variable Frequency Oscillator 7 General description of the optical disk cartridge The optical disk cart
25、ridge which is the subject of this International Standard consists of a case containing an optical disk. The case is a protective enclosure for the disk. It has access windows covered by a shutter. The windows are automatically uncovered by the drive when the cartridge is inserted into it. ISO/IEC l
26、OO!IO:1992 (E) The optical disk is recordable on one side. Data can be written onto the disk as marks in the form of magnetic domains in the recording layer and can be erased from it with a focussed optical beam, using the thermo-magnetic effect. The data can be read with a focussed optical beam, us
27、ing the magneto-optical effect. The beam accesses the recording layer through the transparent substrate of the disk. Part of the disk or the entire disk may contain read-only data in the form of pits embossed by the manufacturer. This data can be read using the diffraction of the optical beam by the
28、 embossed pits. 8 General requirements 8.1 Environments 8.1.1 Testing environment The test environment is the environment where the air immediately surrounding the optical disk cartridge has the following properties: Temperature : 23 “C f 2 “C Relative humidity : 45 % to 55 % Atmospheric pressure :
29、6OkPato 106kPa Air cleanliness : Class 100 000 (see annex M) No condensation on or in the optical disk cartridge shall occur. Before testing, the optical disk cartridge shall be conditioned in this environment for 48 h minimum. It is recommended that, before testing, the entrance surface of the opti
30、cal disk shall be cleaned according to the instructions of the manufacturer of the disk. Unless otherwise stated, all tests and measurements shall be made in this test environment. 8.1.2 Operating environment This International Standard requires that an optical disk cartridge which meets all require
31、ments of this International Standard in the specified test environment provides data interchange over the specified ranges of environmental parameters in the operating environment. The operating environment is the environment where the air immediately surrounding the optical disk cartridge has the f
32、ollowing properties: Temperature Relative humidity Absolute humidity Atmospheric pressure Temperature gradient Relative humidity gradient Air cleanliness Magnetic field strength at the recording layer for any condition under which a beam is in focus Magnetic field strength at the recording layer dur
33、ing any other condition :5cto50”c :3%to85% : 1 g/m3t030g/m3 :60kPato 106kPa : 10 “C/h max. : 10 %/h max. : Office environment (see annex Q) :32OOOA/mmax. :48OOOA/mmax. No condensation on or in the optical disk cartridge shall occur. If an optical disk cartridge has been exposed to conditions outside
34、 those specified in this clause, it shall be acclimatized in an allowed operating environment for at least 2 h before use (see also annex L). 4 lSO/IEC 10090:1992 (E) 8.1.3 Storage environment The optical disk cartridge without any protective enclosure shall not be stored in an environment outside t
35、he range aIlowed for storage. The storage environment is defined as an environment where the air immediately surrounding the optical disk cartridge has the following properties: Temperature : -10 “C to 50 “C Relative humidity :3%to90% Absolute humidity : lg/m3t030gjm3 Atmospheric pressure :6OkPato 1
36、06kPa Temperature gradient : 15 “C/h max. Relative humidity gradient : 10 o/o/h max. Air cleanliness : Office environment (see annex Q) Magnetic field strength at the recording layer : 48 000 A/m max. No condensation on or in the optical disk cartridge shall occur. 8.1.4 Transportation This Internat
37、ional Standard does not specify requirements for transportation; guidance is given in annex P. 8.2 Temperature shock The optical disk cartridge shall withstand a temperature shock of up to 20 “C when inserted into, or removed from, the drive. 8.3 Safety requirements The cartridge shall satisfy the s
38、afety requirements of IEC 950, when used in the intended manner or in any foreseeable use in an information processing system. 8.4 Flammability The cartridge and its components shall be made from materials that comply with the flammability class for HB materials, or better, as specified in IEC 950.
39、9 Reference Drive The Reference Drive is a drive several critical components of which have well defined properties and which is used to test write, read and erase parameters of the disk for conformance to this International Standard. The critical components vary from test to test. This clause gives
40、an outline of all components; components critical for tests in specific clauses only are specified in these clauses. 9.1 Optical system The basic set-up of the optical system of the Reference Drive used for measuring the write, read and erase parameters is shown in figure 1. Different components and
41、 locations of components are permitted, provided that the performance remains the same as that of the set-up in figure 1. 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. ISO
42、/IEC 10090:1992 (E) 11 12 ,-. I I I I I I I I I I I I I I I I I I I - LLJ Ll u A Laser diode B Collimator lens C Optional shaping prism Ch.1 Channel 1 Ch.2 Channel 2 D Beam splitter E Polarizing beam splitter F Objective lens G Optical disk H Optional half-wave plate I Phase retarder J Polarizing be
43、am splitter K,K, Photodiodes for channels 1 and 2 K3 Split photodiode L, ,L, d.c.-coupled amplifiers M Tracking channel (see 20.3) Figure 1 - Optical system of the Reference Drive In the absence of polarization changes in the disk, the polarizing beam splitter J shall be aligned to make the signal o
44、f detector K, equal to that of detector K,. The direction of polarization in this case is called the neutral direction. The phase retarder I shall be adjusted such that the optical system does not have more than 2,5 phase retardation between the neutral polarization and the polarization perpendicula
45、r to it. This position of the retarder is called the neutral position. The phase retarder can be used for the measurement of the narrow-band signal-to-noise ratio (see 26.2). The beam splitter J shall have a p-s intensity reflectance ratio of at least 100. Ihe beam splitter E shall have an intensity
46、 reflectance R, from F to H of nominally 0,30 for the neutral polarization direction. The reflectance R, for the polarization perpendicular to the neutral direction shall be nominally 0,95. The actual value of R, shall not be smaller than 0,90. The imbalance of the magneto-optical signal is specifie
47、d for a beam splitter with nominal reflectances. If the measurement is made on a drive with reflectances R, and R, for beam splitter E, then the measured imbalance shall be multiplied by to make it correspond to the nominal beam splitter E. 6 ISO/IEC 10090:1992 (E) The output of Channel 1 is the sum
48、 of the currents through photodiodes K, and K, and is used for reading embossed marks. The output of Channel 2 is the difference between photodiode currents, and is used for reading user-written marks with the magneto-optical effect. 9.2 Optical beam The focussed optical beam used for writing, readi
49、ng and erasing data shall have the following properties for both wavelengths: Wavelengths (h) + 15nm 780 nm _ lonm + 15Ml 825 nm - 1oMl b) c) 4 6 f) Ii9 Wavelength (h) divided by the numerical aperture of the objective lens (NA) h/NA = 1,475 pm f 0,035 pm for 780 nm ?JNA = 1,560 pm f 0,040 pm for 825 nm Filling D/W of the aperture of the objective lens 1,O max. Variance of the wavefront of the optical beam near the recording layer A2 / 180 max. Polarization parallel to the track Extinction ratio 0,Ol max. The optica
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