1、TECHNICAL REPORT ISO/IEC TR 13841 First edition 1995-07-01 Information technology - Guidance on measurement techniques for 90 mm optical disk cartridges Technologies de /information - Lignes directrices pour /es techniques de mesurage des cartouches de disque optique de diamktre 90 mm q m , Referenc
2、e number lSO/IEC TR 13841 :I 995(E) ISO/IEC TR 13841:1995(E) Contents 1. General 1.1 Scope 1.2 Purpose 1.3 Reference 1.4 Definitions 2 Measurement environments 2.1 General 2.2 Measurement environment A 2.3 Measurement environments B 2.4 Measurement environment C 3 Measurement set up 3.1 General 3.2
3、Measurement accuracy 3.3 Calibration disk 3.4 Measurement area 3.5 Reference Servo 4 Items for measurement techniques 4.1 General 4.2 List of measurement items 5 Measurement techniques 5.1 Shutter opening force 5.1.1 Definition 5.1.2 Measurement procedure 5.2 Clamping force 5.2.1 Introduction 5.2.2
4、Measurement procedure 5.3 Tilt 5.3.1 Introduction 5.3.2 Measurement method 1 5.3.3 Measurement method 2 5.4 Axial and Radial acceleration 5.4.1 Introduction 5.4.2 Measurement system 5.4.3 Procedure 1: Low-pass measurement system 5.4.4 Procedure 2: High-pass Measurement System 5.4.5 Procedure 3: Tota
5、l measurement system 5.5 Reflectance 3 3 3 3 3 3 4 4 4 4 4 4 5 5 7 7 7 7 8 9 14 0 ISO/IEC 1995 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, witho
6、ut permission in writing from the publisher. ISO/IEC Copyright Office l Case postale 56 l CH-1211 Geneve 20 l Switzerland Printed in Switzerland ii 0 IS0 ISOfiEC TR 13841: 1995(E) 5.6 Capture cylinder 5.7 Signals from grooves 5.7.1 Measurement equipment 5.7.2 Measurement conditions 5.7.3 Measuring p
7、rocedure 5.8 Signals from headers 5.8.1 General 5.8.2 Amplitude measurement 5.9 Read power 5.9.1 Definition 5.9.2 Measurement conditions 5.9.3 Measuring procedure 5.9.4 Analysis 5.10 Write power and erase power 5.10.1 Definition 5.10.2 Measurement conditions 5.10.3 Measuring procedure 5.10.4 Analysi
8、s 5.11 Imbalance of the magneto-optical signal 5.11.1 Measurement condition 5.11.2 Measuring procedure 5.12 Narrow-Band Signal-to-Noise Ratio (NBSNR) 5.12.1 Definition 5.12.2 Measurement conditions 512.3 Measuring procedure Annexes A - The flow chart for determining write power and erase power B - A
9、veraging Times and Spectrum Analyzer Data C - Measurement Frequency Point for Noise Level D - Notes on Measuring Noise Level E - Example of measurement procedure of signals from grooves F - The Measuring Method of The Capture Cylinder Radius for the Hub G - Better noise measurement with the HP3585A
10、- type 2, when the subject is still under technical development or where for any other reason there is the future but not immediate possibility of an agreement on an International Standard; - type 3, when a technical committee has collected data of a different kind from that which is normally publis
11、hed as an International Standard (“state of the art”, for example). Technical Reports of types 1 and 2 are subject to review within three years of publication, to decide whether they can he transformed into International Standards. Technical Reports of type 3 do not necessarily have to be reviewed u
12、ntil the data they provide are considered to be no longer valid or useful. ISO/IEC TR 13841, which is a Technical Report of type 3, was prepared by Joint Technical Committee ISO/IEC JTC 1, Information technology. TECHNICAL REPORT 0 ISO/IEC ISO/IEC TR 13841:1995(E) Information technology - Guidance o
13、n measurement techniques for 90 mm optical disk cartridges 1 General 1.1 Scope This technical report provides Guidance on Measurement Techniques for 90 mm Rewritable/Read-only Optical Disk Cartridges. 1.2 Purpose This technical report provides guidance on measurement techniques which are not well un
14、derstood in industry. The basic concept of this report is to aid in the understanding of interchangeability between disks and drives. This report gives guidance and provides some examples of measurement techniques to aid this understanding. 13 Reference ISO/IEC 10090: 1992, Information technology -
15、90 mm optical disk cartridges, rewritable and read only, for data interchange. 1.4 Definitions The definitions of this report are the same as the definitions of ISO/IEC 10090. 2 Measurement environments 2.1 General This report recommends 3 kinds of measurement environments. Each clause in section 5
16、may use 1 of 3 measurement environments as specified in this section. Basically, Measurement environment A is used for each clause in section 5 unless noted. Additional environments or conditions are recommended in each clause. 2.2 Measurement environment A Measurement environment A is the same as t
17、he testing environment of ISO/IEC 10090 i.e. temperature : 23 “C*2 “C relative humidity : 45% to 55% atmospheric pressure : 60kPato 106kRa air cleanliness : Class 100 000 magnetic field strength : 32OOOA/mmax. 2.3 Measurement environments B Measurement environments B are used for the highest tempera
18、ture marginal test temperature : 50 “C P/T = 6*SD/Tolerance 0.2 where SD is the standard deviation and Tolerance is the upper limit minus the lower limit of the specification. For example: In the case of reflectance P/T = 6* SD/(0,29-0,14) 0,2 i.e. SD 0,005 In the case of single ended specifications
19、, the system should be capable of resolving the number of significant digits in the parameter specification. 3.3 Calibration disk The laser power of the optical drive and/or the measurement equipment on the recording layer can be calibrated from the calibration disk which is provided by the Reliabil
20、ity Center for Electronic Components of Japan (RCJ) Note - This calibration disk cartridge has been established by RCJ, l-l-2 Hachiman Higashikurume Tokyo. Japan, and can be ordered under Part number JCM6272 until 2002. 3.4 Measurement area ISO/IEC 10090 requires disks to satisfy specifications in a
21、ll the areas of the disk unless noted. (See annex R in ISO/IEC 10090). This report shows the most critical measurement areas in each clause, as follows: (A) Innermost diameter is critical (R=24mm) for Read power, NBSNR, Signal from headers (Ivfo , Idmax /Idmin), Push-pull signal and cross-track sign
22、al in ROM area (B) Correspond to control track data ( R=24mm, 30mm, 40mm) Write power, Erase power (C) Outermost diameter is critical (R=40mm) for Tilt, Axial and radial accelerations, (D) Outermost and innermost diameters are critical (R=24mm, 40mm) for Reflectance, Imbalance of the MO signal (E) I
23、nner and outer test zones and control zones. Signal from grooves and headers 3.5 Reference Servo ISO/IEC 10090 specifies a disk rotational frequency of 30Hz for testing conditions and specifies the transfer functions of the Reference Servo for axial and radial tracking of the recording layer. (See 9
24、.5 and 11.4 of ISO/IEC 10090.) During the measurement of the signals, the radial tracking error between the focus of the optical beam and the center of a track is made smaller than during the measurement of the radial acceleration. This is achieved by a strong servo as provided in 20.2.4. Therefore
25、the 0,l pm value of the radial tracking error is increased below the acceleration cross-over frequency and is not changed in the frequency range higher than the acceleration cross-over frequency. There are various strong servos using various phase compensators. If one uses the same type of compensat
26、or (C=3) as the reference servo, the 0 cross frequency of this strong servo on the rotational speed of 30 Hz is 1 500 Hz. And this strong servo has an acceleration cross- over frequency of 870 Hz. For other rotational frequencies, see table 1. 2 0 ISOAEC ISO/IEC TR 13841: 1995 (E) Table 1. Constants
27、 table for the measurement servos Note: The bold values are the values calculated for the reference servo. 4 Items for measurement techniques 4.1 General The following list shows the status of each item. The list classifies these items into 2 groups : 1) guidance on definition and measurement techni
28、ques, 2) guidance on measurement techniques. 4.2 List of measurement items Clause number Title in ISOAEC 10090 10.4.5 Shutter opening force 12.2 Clamping force 11.4.9 Tilt 11.4.8 Radial and axial acceleration 11.5.4 Reflectance 12.3 Capture cylinder 21 Signals from grooves 22 Signals from headers 24
29、.2.2 Read power 24.3.2124.4.1 Write power and Erase power 25.2 Imbalance of the MO 26.2 Narrow-band signal-to-noise ratio 5 Measurement techniques 5.1 Shutter opening force status (1) (2) (1) (2) (2) (2) (2) (2) (1) (1) (2) (2) Clause number 5.1 5.2 5.3 5.4 5.5 5.6 5.7 5.8 5.9 5.10 5.11 5.12 5.1.1 D
30、efinition The shutter opening force is defined as the maxirnum force including shutter weight and friction between the cartridge and shutter when opening and/or closing the shutter. It is measured as the force in pushing or pulling the shutter parallel to the shutter movement. But the friction force
31、 caused by the shutter-opener in the drive mechanism is not included in the definition. 3 ISO/IEC TR 13841: 1995 (E) 01s0/IEc 5.1.2 Measurement procedure The measurement is done by using a tension gauge as shown in figure 1. This measurement method does not include shutter weight. Therefore, the shu
32、tter weight must be added to the result of the measurement. Another method and measurement data are shown in annex H. Cartridge Tension gauge Type; Teclock DT-1OOG Figure 1 - An example of measurement setup 5.2 Clamping force 5.2.1 Introduction The maximum allowable force is within a range from clam
33、ping a disk without deterioration mechanical characteristics of the disk to unloading the disk by a force of the loading motor or mechanism. The clamping force is checked by the disk with an upper or lower limit of hub which meets the requirement of annex K in ISO/IEC 10090. This item is determined
34、by the drive design. 5.2.2 Measurement procedure 1. Prepare the magnetizable material for a hub which is able to provide the adsorbent force of 4,5 N on the tester in annex K in ISO/IEC 10090. 2. Adhere the material on the non-magnetizable hub with height accuracy of 1,20*0,01 mm including paralleli
35、sm of the substrate and the material. 3. Clamp the disk on the turntable of the test drive. 4. Measure the clamping force by pulling off the disk. 53 Tilt 5.3.1 Introduction Tilt is defined as the angle between the reference plane of a disk and the entrance surface in the text of the ISO/IEC 10090.
36、The accuracy of the substrate thickness is also considered when the reflectance light is utilized from the recording layer in 4 0 ISO/IEC ISOAEC TR 13841: 1995 (E) the real measurement. There exist several methods and this report shows following two methods of the measurement. The first method is of
37、 the similar method defined in the sentence of the ISOAEC 10090, that is, to measure the tilt with a parallel light beam directly. The second one is to measure the tilt with a special head utilized over the measurement of the mechanical characteristics. 5.3.2 Measurement method 1 This has been used
38、for long time and the principle of the measurement is depicted in figure 3. When a small He-Ne laser, for example, is used as a light source, the spot size of the measurement is approximately 1 mm. Therefore, this method is mostly close to the sentence defined in ISO/IEC 10090. However, following co
39、nditions should be considered in this measurement. (A)The spot size should be kept in the range of 1 mm when the outermost area is measured. (B)The error increase depends on the substrate thickness, when the tilt increases. 53.3 Measurement method 2 This is a method to measure tilt by the axial defl
40、ection values. In order to measure the axial deflection, the position of the objective lens is detected either with a head, which is specially designed within a micro-sensor or by an electric current to the lens actuator. These methods are more convenient for measurement method 1 because the other m
41、echanical characteristics are also measured simultaneously. The method to determine a tilt by the axial deflection is explained in figure 2. Assuming a small square within a few mm2 as a flat plane, the tilt along the radius (t&) or along tangential (00) direction is calculated by the axial directio
42、n difference of separated two points (Al, Bl or A2, Al) and the distance (1, or 10) respectively. Tangential tilt angle Radial tilt angle +e= tan - l(AdWle) = tan - l(Al-DA2)/ 1) &= tan - l(Adr/-l,) = tan - l(Al-DBl)/ 1,) Therefore, compounded solid angle (tilt angle) is, Tilt angle I= SQRT (+e2+$r2
43、) However, this equation must be used carefully for the following reasons. (A)Tilt is determined by the axial deflection difference as function of the distance. That is, the shorter the distance of the separated points (le,l,) is, the more estimated error increases. Oppositely, in the case of the lo
44、nger distance, the surface roughness disturbs the measurement. Therefore, the measurement conditions must be well considered. (B)The axial deflection value of 5 pm should correspond to 5 mrad of the specification when tilt is measured every 1 mm pitch. Therefore, the measurement accuracy must be also considered. 5
