IEC 61747-20-2:2015

IEC 61747-20-2 ®
Edition 1.0 2015-03
INTERNATIONAL
STANDARD
Liquid crystal display devices –
Part 20-2: Visual inspection – Monochrome matrix liquid crystal display modules
(excluding all active matrix liquid crystal display modules)
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, without permission in writing from
either IEC or IEC's member National Committee in the country of the requester. If you have any questions about IEC
copyright 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.

IEC Central Office Tel.: +41 22 919 02 11
3, rue de Varembé Fax: +41 22 919 03 00
CH-1211 Geneva 20 info@iec.ch
Switzerland www.iec.ch
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.

About IEC publications
The technical content of IEC publications 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.

IEC Catalogue - webstore.iec.ch/catalogue Electropedia - www.electropedia.org
The stand-alone application for consulting the entire The world's leading online dictionary of electronic and
bibliographical information on IEC International Standards, electrical terms containing more than 30 000 terms and
Technical Specifications, Technical Reports and other definitions in English and French, with equivalent terms in 15
documents. Available for PC, Mac OS, Android Tablets and additional languages. Also known as the International
iPad. Electrotechnical Vocabulary (IEV) online.

IEC publications search - www.iec.ch/searchpub IEC Glossary - std.iec.ch/glossary
The advanced search enables to find IEC publications by a More than 60 000 electrotechnical terminology entries in
variety of criteria (reference number, text, technical English and French extracted from the Terms and Definitions
committee,…). It also gives information on projects, replaced clause of IEC publications issued since 2002. Some entries
and withdrawn publications. have been collected from earlier publications of IEC TC 37,

77, 86 and CISPR.
IEC Just Published - webstore.iec.ch/justpublished
Stay up to date on all new IEC publications. Just Published IEC Customer Service Centre - webstore.iec.ch/csc
details all new publications released. Available online and If you wish to give us your feedback on this publication or
also once a month by email. need further assistance, please contact the Customer Service
Centre: csc@iec.ch.
IEC 61747-20-2 ®
Edition 1.0 2015-03
INTERNATIONAL
STANDARD
Liquid crystal display devices –

Part 20-2: Visual inspection – Monochrome matrix liquid crystal display modules

(excluding all active matrix liquid crystal display modules)

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 31.120 ISBN 978-2-8322-2391-8

– 2 – IEC 61747-20-2:2015 © IEC 2015
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Normative references. 6
3 Terms, definitions and abbreviations . 6
3.1 Terms and definitions . 6
3.2 Abbreviations . 6
4 Visual inspection method and criteria . 6
4.1 Standard inspection conditions and methods . 6
4.1.1 Ambient conditions . 6
4.1.2 Inspection equipment and liquid crystal display modules . 7
4.1.3 Inspector and limit sample for visual inspection . 7
4.1.4 Inspection and record of result . 7
4.2 Visual inspection of display . 7
4.2.1 Display not activated . 7
4.2.2 Display activated . 9
Bibliography . 13

Figure 1 – Defects within the viewing area . 8
Figure 2 – Deviations and mis-shapes of a square picture element . 9
Figure 3 – Notched edges of picture elements . 9
Figure 4 – Defects within the elements and their surroundings . 10

Table 1 –Defects and criteria when display not activated . 8
Table 2 – Properties and criteria when display activated . 10
Table 3 – Defects and criteria when display activated . 10
Table 4 – Defect and criteria of viewing area . 12

INTERNATIONAL ELECTROTECHNICAL COMMISSION
_____________
LIQUID CRYSTAL DISPLAY DEVICES –

Part 20-2: Visual inspection – Monochrome matrix liquid crystal display
modules (excluding all active matrix liquid crystal display modules)

FOREWORD
1) The International Electrotechnical 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. 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 National 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 (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 representation 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 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. 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, access 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 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
expenses 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 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 61747-20-2 has been prepared by IEC technical committee 110:
Electronic display devices.
This first edition cancels and replaces Clause 5 of the first edition of IEC 61747-5 published in
1998. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) editorial modification was done in accordance with the ISO/IEC Directives, Part 2;
b) document n
...