《IEC-62220-1-2003.pdf》由会员分享，可在线阅读，更多相关《IEC-62220-1-2003.pdf（36页珍藏版）》请在三一文库上搜索。
1、INTERNATIONAL STANDARD IEC 62220-1 First edition 2003-10 Medical electrical equipment Characteristics of digital X-ray imaging devices Part 1: Determination of the detective quantum efficiency Appareils lectromdicaux Caractristiques des appareils dimagerie rayonnement X Partie 1: Dtermination de lef
2、ficacit quantique de dtection Reference number IEC 62220-1:2003(E) Copyright International Electrotechnical Commission Provided by IHS under license with IECLicensee=IHS Employees/1111111001, User=Wing, Bernie Not for Resale, 03/10/2007 04:49:03 MSTNo reproduction or networking permitted without lic
3、ense from IHS -,-,- Publication numbering As from 1 January 1997 all IEC publications are issued with a designation in the 60000 series. For example, IEC 34-1 is now referred to as IEC 60034-1. Consolidated editions The IEC is now publishing consolidated versions of its publications. For example, ed
4、ition numbers 1.0, 1.1 and 1.2 refer, respectively, to the base publication, the base publication incorporating amendment 1 and the base publication incorporating amendments 1 and 2. Further information on IEC publications The technical content of IEC publications is kept under constant review by th
5、e IEC, thus ensuring that the content reflects current technology. Information relating to this publication, including its validity, is available in the IEC Catalogue of publications (see below) in addition to new editions, amendments and corrigenda. Information on the subjects under consideration a
6、nd work in progress undertaken by the technical committee which has prepared this publication, as well as the list of publications issued, is also available from the following: IEC Web Site (www.iec.ch) Catalogue of IEC publications The on-line catalogue on the IEC web site (www.iec.ch/searchpub) en
7、ables you to search by a variety of criteria including text searches, technical committees and date of publication. On-line information is also available on recently issued publications, withdrawn and replaced publications, as well as corrigenda. IEC Just Published This summary of recently issued pu
8、blications (www.iec.ch/online_news/ justpub) is also available by email. Please contact the Customer Service Centre (see below) for further information. Customer Service Centre If you have any questions regarding this publication or need further assistance, please contact the Customer Service Centre
9、: Email: custserviec.ch Tel: +41 22 919 02 11 Fax: +41 22 919 03 00 Copyright International Electrotechnical Commission Provided by IHS under license with IECLicensee=IHS Employees/1111111001, User=Wing, Bernie Not for Resale, 03/10/2007 04:49:03 MSTNo reproduction or networking permitted without li
10、cense from IHS -,-,- INTERNATIONAL STANDARD IEC 62220-1 First edition 2003-10 Medical electrical equipment Characteristics of digital X-ray imaging devices Part 1: Determination of the detective quantum efficiency Appareils lectromdicaux Caractristiques des appareils dimagerie rayonnement X Partie 1
11、: Dtermination de lefficacit quantique de dtection IEC 2003 Copyright - all rights reserved No part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from the publisher. Interna
12、tional Electrotechnical Commission, 3, rue de Varemb, PO Box 131, CH-1211 Geneva 20, Switzerland Telephone: +41 22 919 02 11 Telefax: +41 22 919 03 00 E-mail: inmailiec.ch Web: www.iec.ch U For price, see current catalogue PRICE CODE Commission Electrotechnique Internationale International Electrote
13、chnical Commission Copyright International Electrotechnical Commission Provided by IHS under license with IECLicensee=IHS Employees/1111111001, User=Wing, Bernie Not for Resale, 03/10/2007 04:49:03 MSTNo reproduction or networking permitted without license from IHS -,-,- 2 62220-1 IEC:2003(E) CONTEN
14、TS FOREWORD 3 INTRODUCTION 5 1Scope 6 2Normative references. 6 3Terminology and definitions . 7 4Requirements 8 4.1Operating conditions. 8 4.2X-RAY EQUIPMENT 8 4.3RADIATION QUALITY 9 4.4TEST DEVICE.10 4.5Geometry.11 4.6IRRADIATION conditions.13 4.6.1General conditions.13 4.6.2Exposure measurement .1
15、3 4.6.3Avoidance of LAG EFFECTS14 4.6.4IRRADIATION to obtain the CONVERSION FUNCTION.14 4.6.5IRRADIATION for determination of the NOISE POWER SPECTRUM14 4.6.6IRRADIATION with TEST DEVICE in the RADIATION BEAM.15 5Corrections of RAW DATA.16 6Determination of the DETECTIVE QUANTUM EFFICIENCY.16 6.1Def
16、inition and formula of DQE(u,v) .16 6.2Parameters to be used for evaluation 17 6.3Determination of different parameters from the images17 6.3.1Linearization of data 17 6.3.2The NOISE POWER SPECTRUM (NPS).18 6.3.3Determination of the MODULATION TRANSFER FUNCTION (MTF)20 7Format of conformance stateme
17、nt.20 8Accuracy.21 Annex A (normative) Determination of LAG EFFECTS23 A.1Test of additive LAG EFFECTS23 A.2Test of multiplicative LAG EFFECTS24 Annex B (normative) Terminology Index of defined terms26 Annex C (informative) Calculation of the input NOISE POWER SPECTRUM.27 Bibliography28 Copyright Int
18、ernational Electrotechnical Commission Provided by IHS under license with IECLicensee=IHS Employees/1111111001, User=Wing, Bernie Not for Resale, 03/10/2007 04:49:03 MSTNo reproduction or networking permitted without license from IHS -,-,- 62220-1 IEC:2003(E) 3 INTERNATIONAL ELECTROTECHNICAL COMMISS
19、ION _ MEDICAL ELECTRICAL EQUIPMENT CHARACTERISTICS OF DIGITAL X-RAY IMAGING DEVICES Part 1: Determination of the detective quantum efficiency FOREWORD 1)The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising all national electrotechnical commit
20、tees (IEC National Committees). The object of IEC is to promote international co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical
21、Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with may participate in this preparatory work. International, governmental a
22、nd non- governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for Standardization (ISO) in accordance with conditions determined by agreement between the two organizations. 2)The formal decisions or agreeme
23、nts of IEC on technical matters express, as nearly as possible, an international consensus of opinion on the relevant subjects since each technical committee has representation from all interested IEC National Committees. 3)IEC Publications have the form of recommendations for international use and
24、are accepted by IEC National Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any misinterpretation by any end user. 4)In order to promote int
25、ernational uniformity, IEC National Committees undertake to apply IEC Publications transparently to the maximum extent possible in their national and regional publications. Any divergence between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
26、 the latter. 5)IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any equipment declared to be in conformity with an IEC Publication. 6)All users should ensure that they have the latest edition of this publication. 7)No liability shall attach to IEC or
27、its directors, employees, servants or agents including individual experts and members of its technical committees and IEC National Committees for any personal injury, property damage or other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and expense
28、s arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC Publications. 8)Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is indispensable for the correct application of this publication. 9)Attention
29、 is drawn to the possibility that some of the elements of this IEC Publication may be the subject of patent rights. IEC shall not be held responsible for identifying any or all such patent rights. International Standard IEC 62220-1 has been prepared by subcommittee 62B: Diagnostic imaging equipment,
30、 of IEC technical committee 62: Electrical equipment in medical practice. The text of this standard is based on the following documents: FDISReport on voting 62B/493/FDIS62B/506/RVD Full information on the voting for the approval of this standard can be found in the report on voting indicated in the
31、 above table. This publication has been drafted in accordance with the ISO/IEC Directives, Part 2. Copyright International Electrotechnical Commission Provided by IHS under license with IECLicensee=IHS Employees/1111111001, User=Wing, Bernie Not for Resale, 03/10/2007 04:49:03 MSTNo reproduction or
32、networking permitted without license from IHS -,-,- 4 62220-1 IEC:2003(E) In this standard, terms printed in SMALL CAPITALS are used as defined in IEC 60788, in Clause 3 of this standard or other IEC publications referenced in Annex B. Where a defined term is used as a qualifier in another defined o
33、r undefined term it is not printed in SMALL CAPITALS, unless the concept thus qualified is defined or recognized as a “derived term without definition”. NOTE Attention is drawn to the fact that, in cases where the concept addressed is not strongly confined to the definition given in one of the publi
34、cations listed above, a corresponding term is printed in lower-case letters. The committee has decided that the contents of this publication will remain unchanged until 2006-12. At this date, the publication will be reconfirmed; withdrawn; replaced by a revised edition, or amended. Copyright Interna
35、tional Electrotechnical Commission Provided by IHS under license with IECLicensee=IHS Employees/1111111001, User=Wing, Bernie Not for Resale, 03/10/2007 04:49:03 MSTNo reproduction or networking permitted without license from IHS -,-,- 62220-1 IEC:2003(E) 5 INTRODUCTION DIGITAL X-RAY IMAGING DEVICES
36、 are increasingly used in medical diagnosis and will widely replace conventional (analogue) imaging devices such as screen-film systems or analogue X- RAY IMAGE INTENSIFIER television systems in the future. It is necessary, therefore, to define parameters that describe the specific imaging propertie
37、s of these DIGITAL X-RAY IMAGING DEVICES and to standardize the measurement procedures employed. There is growing consensus in the scientific world that the DETECTIVE QUANTUM EFFICIENCY (DQE) is the most suitable parameter for describing the imaging performance of an X-ray imaging device. The DQE de
38、scribes the ability of the imaging device to preserve the signal-to- NOISE ratio from the radiation field to the resulting digital image data. Since in X-ray imaging, the NOISE in the radiation field is intimately coupled to the exposure level, DQE values can also be considered to describe the dose
39、efficiency of a given imaging device. NOTE 1 In spite of the fact that the DQE is widely used to describe the performance of imaging devices, the connection between this physical parameter and the decision performance of a human observer is not yet completely understood 1, 3.1) NOTE 2 The standard I
40、EC 61262-5 specifies a method to determine the DQE of X-RAY IMAGE INTENSIFIERS at nearly zero SPATIAL FREQUENCY. It focuses only on the electro-optical components of X-RAY IMAGE INTENSIFIERS, not on the imaging properties as this standard does. As a consequence, the output is measured as an optical
41、quantity (luminance), and not as digital data. Moreover, IEC 61262-5 prescribes the use of a RADIATION SOURCE ASSEMBLY, whereas this standard prescribes the use of an X-RAY TUBE. The scope of IEC 61262-5 is limited to X-RAY IMAGE INTENSIFIERS and does not interfere with the scope of this standard. T
42、he DQE is already widely used by manufacturers to describe the performance of their equipment. The specification of the DQE is also required by regulatory agencies (such as the Food and Drug Administration (FDA) for admission procedures. However, there is presently no standard governing either the m
43、easurement conditions or the measurement procedure with the consequence that values from different sources may not be comparable. This standard has therefore been developed in order to specify the measurement procedure together with the format of the conformance statement for the DETECTIVE QUANTUM E
44、FFICIENCY of DIGITAL X-RAY IMAGING DEVICES. In the DQE calculations proposed in this standard, it is assumed that system response is measured for objects that attenuate all energies equally (task-independent) 5. The standard will be beneficial for manufacturers, users, distributors and regulatory ag
45、encies. It can be regarded as the first of a series describing all the relevant parameters of DIGITAL X- RAY IMAGING DEVICES. 1) Figures in square brackets refer to the bibliography. Copyright International Electrotechnical Commission Provided by IHS under license with IECLicensee=IHS Employees/1111
46、111001, User=Wing, Bernie Not for Resale, 03/10/2007 04:49:03 MSTNo reproduction or networking permitted without license from IHS -,-,- 6 62220-1 IEC:2003(E) MEDICAL ELECTRICAL EQUIPMENT CHARACTERISTICS OF DIGITAL X-RAY IMAGING DEVICES Part 1: Determination of the detective quantum efficiency 1 Scop
47、e This part of IEC 62220 specifies the method for the determination of the DETECTIVE QUANTUM EFFICIENCY (DQE) of DIGITAL X-RAY IMAGING DEVICES as a function of exposure and of SPATIAL FREQUENCY for the working conditions in the range of the medical application as specified by the MANUFACTURER. This
48、part of IEC 62220 is applicable to projection DIGITAL X-RAY IMAGING DEVICES producing IMAGES in digital format that are used for medical diagnosis. It is restricted to DIGITAL X-RAY IMAGING DEVICES that are used for radiographic imaging, such as CR systems, selenium-based systems, flat panel detectors, optically coupled CCD detectors, and digital X-RAY IMAGE INTENSIFIERS used for single exposures. This part of IEC 62220 is not applicable to