1、 IEC/TR 62728 Edition 1.0 2011-09 TECHNICAL REPORT Display technologies LCD, PDP and OLED Overview and explanation of differences in terminology IEC/TR 62728:2011(E) THIS PUBLICATION IS COPYRIGHT PROTECTED Copyright 2011 IEC, Geneva, Switzerland All rights reserved. Unless otherwise specified, no pa
2、rt 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 either IEC or IECs member National Committee in the country of the requester. If you have any questions about IEC copyr
3、ight or have an enquiry about obtaining additional rights to this publication, please contact the address below or your local IEC member National Committee for further information. Droits de reproduction rservs. Sauf indication contraire, aucune partie de cette publication ne peut tre reproduite ni
4、utilise sous quelque forme que ce soit et par aucun procd, lectronique ou mcanique, y compris la photocopie et les microfilms, sans laccord crit de la CEI ou du Comit national de la CEI du pays du demandeur. Si vous avez des questions sur le copyright de la CEI ou si vous dsirez obtenir des droits s
5、upplmentaires sur cette publication, utilisez les coordonnes ci-aprs ou contactez le Comit national de la CEI de votre pays de rsidence. IEC Central Office 3, rue de Varemb CH-1211 Geneva 20 Switzerland Email: inmailiec.ch Web: www.iec.ch About IEC publications The technical content of IEC publicati
6、ons is kept under constant review by the IEC. Please make sure that you have the latest edition, a corrigenda or an amendment might have been published. Catalogue of IEC publications: www.iec.ch/searchpub The IEC on-line Catalogue enables you to search by a variety of criteria (reference number, tex
7、t, technical committee,). It also gives information on projects, withdrawn and replaced publications. IEC Just Published: www.iec.ch/online_news/justpub Stay up to date on all new IEC publications. Just Published details twice a month all new publications released. Available on-line and also by emai
8、l. Electropedia: www.electropedia.org The worlds leading online dictionary of electronic and electrical terms containing more than 20 000 terms and definitions in English and French, with equivalent terms in additional languages. Also known as the International Electrotechnical Vocabulary online. Cu
9、stomer Service Centre: www.iec.ch/webstore/custserv If you wish to give us your feedback on this publication or need further assistance, please visit the Customer Service Centre FAQ or contact us: Email: csciec.ch Tel.: +41 22 919 02 11 Fax: +41 22 919 03 00 IEC/TR 62728 Edition 1.0 2011-09 TECHNICA
10、L REPORT Display technologies LCD, PDP and OLED Overview and explanation of differences in terminology INTERNATIONAL ELECTROTECHNICAL COMMISSION L ICS 31.120; 31.260 PRICE CODE ISBN 978-2-88912-695-8 Registered trademark of the International Electrotechnical Commission 2 TR 62728 IEC:2011(E) CONTENT
11、S FOREWORD . 3 INTRODUCTION . 5 1 Scope . 6 2 Normative references . 6 3 Covered terms 7 4 Explanation 7 TR 62728 IEC:2011(E) 3 INTERNATIONAL ELECTROTECHNICAL COMMISSION _ DISPLAY TECHNOLOGIES LCD, PDP AND OLED OVERVIEW AND EXPLANATION OF DIFFERENCES IN TERMINOLOGY FOREWORD 1) The International Elec
12、trotechnical Commission (IEC) is a worldwide organization for standardization comprising all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international co-operation on all questions concerning standardization in the electrical and electronic fields.
13、 To this end and in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC Publication(s)”). Their preparation is entrusted to technical committees; any IEC Na
14、tional Committee interested in the subject dealt with may participate in this preparatory work. International, governmental and non- governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for Standardization
15、 (ISO) in accordance with conditions determined by agreement between the two organizations. 2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international consensus of opinion on the relevant subjects since each technical committee has representati
16、on from all interested IEC National Committees. 3) IEC Publications have the form of recommendations for international use and 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
17、 be held responsible for the way in which they are used or for any misinterpretation by any end user. 4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications transparently to the maximum extent possible in their national and regional publications.
18、 Any divergence between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter. 5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity assessment services and, in some areas, acces
19、s to IEC marks of conformity. IEC is not responsible for any services carried out by independent certification bodies. 6) All users should ensure that they have the latest edition of this publication. 7) No liability shall attach to IEC or its directors, employees, servants or agents including indiv
20、idual 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 expenses arising out of the publication, use of, or reliance upon,
21、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 is drawn to the possibility that some of the elements of
22、this IEC Publication may be the subject of patent rights. IEC shall not be held responsible for identifying any or all such patent rights. The main task of IEC technical committees is to prepare International Standards. However, a technical committee may propose the publication of a technical report
23、 when it has collected data of a different kind from that which is normally published as an International Standard, for example “state of the art“. IEC 62728, which is a technical report, has been prepared by IEC technical committee 110: Flat panel display devices. The text of this technical report
24、is based on the following documents: Enquiry draft Report on voting 110/301/DTR 110/320/RVC Full information on the voting for the approval of this technical report can be found in the report on voting indicated in the above table. 4 TR 62728 IEC:2011(E) This publication has been drafted in accordan
25、ce with the ISO/IEC Directives, Part 2. The committee has decided that the contents of this publication will remain unchanged until the stability date indicated on the IEC web site under “http:/webstore.iec.ch“ in the data related to the specific publication. At this date, the publication will be re
26、confirmed, withdrawn, replaced by a revised edition, or amended. TR 62728 IEC:2011(E) 5 INTRODUCTION Traditionally each display technology (LCD, PDP and OLED) has developed its standards independently. However because of the common applications for these technologies (e.g. TV), the differences in th
27、e terms and measurement methods used by the different technologies are causing confusion. In 2007, TC110 decided to establish a study group to address these issues. This group decided to initially address the differences in terminology. Experts representing each working group (working group No.2: LC
28、D, No.4: PDP, and No.5: OLED) agreed to work toward harmonizing their terminology standards at the maintenance time. Cases were found where a standard term differed from International Electrotechnical Vocabulary (IEV), which is used by IEC for basic definitions. In the case where agreement on harmon
29、ization could not be reached the study group decided to explain the reason for the disagreement. This technical report explains the differences of the definitions for 10 terms and the reasons why they are different. It is expected that this report will help consumers to understand these differences
30、and to use these technical terms without confusion. 6 TR 62728 IEC:2011(E) DISPLAY TECHNOLOGIES LCD, PDP AND OLED OVERVIEW AND EXPLANATION OF DIFFERENCES IN TERMINOLOGY 1 Scope This technical report explains differences in definitions of the terms used in the flat panel display field such as liquid
31、crystal displays (LCD), plasma displays (PDP), and organic light emitting diode displays (OLED). The definitions of technical terms are individually specified in the different standards: Liquid crystal display: IEC 61747-1 Plasma display: IEC 61988-1 Organic light emitting diode display: IEC 62341-1
32、-2. This report explains the background and reasons for the differences, but does not introduce new definitions or terms. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undate
33、d references, the latest edition of the referenced document (including any amendments) applies. IEC 60050-845:1987, International Electrotechnical Vocabulary. Lighting IEC 61747-1:1998, Liquid crystal and solid-state display devices Part 1: Generic specification Amendment 1 (2003) IEC 61988-1:2003,
34、Plasma display panels Part 1: Terminology and letter symbols IEC 62341-1-2:2007, Organic light emitting diode displays Part 1-2: Terminology and letter symbols TR 62728 IEC:2011(E) 7 3 Covered terms In this document, explanations on the following terms are provided. Term Subclause active area 4.2.1
35、addressing 4.2.2 aspect ratio 4.2.3 contrast ratio 4.2.4 luminance lifetime 4.2.5 luminous efficacy 4.2.6 luminous efficiency 4.2.7 quantum efficiency 4.2.8 screen area 4.2.1 viewing angle 4.2.10 viewing direction 4.2.10 viewing angle range 4.2.10 4 Explanation 4.1 General Hereafter the standards of
36、 terms and definitions are indicated as IEV for IEC 60050-845:1987, LCD for IEC 61747-1:1998 (and Amendment 1:2003), PDP for IEC 61988-1:2003, and OLED for IEC 62341-1-2:2007, respectively. Note that some definition texts were simplified by omitting Notes. Each clause consists of: defined word(s) de
37、finition in the standard IEV, LCD, PDP, or OLED issues, and explanation. 8 TR 62728 IEC:2011(E) 4.2 Items 4.2.1 active area screen area Definition in LCD Definition in PDP Definition in OLED active area part of a display screen area delimited by picture elements screen area maximum image reproducing
38、 area of the device active area area that has a display function on the substrate of an organic light emitting diode display Issue “Active area” and “screen area” are often used with the same meaning but are defined differently for LCD and PDP. Explanation “Active area” and “screen area” are often u
39、sed with the same meaning. Sometimes “active area” can be regarded as only an area covered by “active” pixels, omitting non-active pixels. To avoid this ambiguity, PDP experts agreed to use the term “screen area” instead, which is more familiar in the market. Since “active area” has also been often
40、used, a note “sometimes called as active area” was added to PDP standard for harmonization. 4.2.2 addressing Definition in LCD Definition in PDP Definition in OLED addressing selecting the pixels in space and/or time for activation or deactivation addressing setting or changing the state of a subpix
41、el with an address pulse Issue “Addressing” is a basic action of the display. The definition of LCD and PDP could not be harmonized. Explanation Since addressing principles for LCD and PDP are quite different, the words for definition need to be different. For LCD, the word “activation” is most suit
42、able to express how to fix the selected pixels to display an image. However this would not be a correct wording for a PDP. A PDP has inherent memory in each subpixel, and so the state of this memory must be altered. This is not an “activate” or “deactivate” operation. Most other display devices do n
43、ot have this memory effect. 4.2.3 aspect ratio Definition in LCD Definition in PDP Definition in OLED aspect ratio ratio of screen width to screen height aspect ratio ratio of active area width to active area height, for example 4:3 or 16:9 Issue Explanation See “active area” (4.2.1) TR 62728 IEC:20
44、11(E) 9 4.2.4 contrast ratio Definition in LCD Definition in PDP Definition in OLED contrast ratio the ratio between the higher, L H and lower, L L luminances that define the feature to be detected, measured by contrast ratio CR, defined as: CR= L H L Lcontrast ratio ratio of white luminance to blac
45、k luminance of the image, including light reflected from the display contrast ratio ratio of white luminance to black luminance of the image, including light reflected from the display Issue The definitions in PDP and OLED are already harmonized, however they are different from the definition in LCD
46、. Explanation Generally, the fundamental function of an LCD is the switching of two phases between bright and dark phases. This does not directly mean “white” and “black” because there are various types of LCD which cannot be simply regarded as white-black, for example “blue-mode” (white/blue) or “y
47、ellow-mode” (yellow/black). So it is suitable for LCD to define “contrast ratio” as the ratio between two fundamental phases. Since the current major applications for PDP and OLED are television or display monitor (including mobile), the colour of the highest luminance can be regarded as “white” and
48、 the lowest as “black” in most of these cases. So for PDP and OLED, it is suitable to define “contrast ratio” as the ratio between “white” and “black”. 4.2.5 luminance lifetime Definition in LCD Definition in PDP Definition in OLED luminance lifetime time period during which the device continues to
49、function at 50% or more of its initial luminance luminance lifetime elapsed time required for the luminance to decrease to a specified fraction of the initial luminance in operation Issue OLED defines this word in a basic manner but PDP includes a specific number, “50 %”. Explanation In the PDP field, “luminance lifetime” has been widely used in specification sheets to express how long
