IEC 62906-5-7:2022

IEC 62906-5-7 ®
Edition 1.0 2022-01
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Laser displays –
Part 5-7: Measuring methods of image quality affected by speckle for scanning
laser displays
Affichages laser –
Partie 5-7: Méthodes de mesure de la qualité d’image affectée par la tacheture
pour les affichages laser à balayage

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.

Droits de reproduction réservés. Sauf indication contraire, aucune partie de cette publication ne peut être reproduite
ni utilisée sous quelque forme que ce soit et par aucun procédé, électronique ou mécanique, y compris la photocopie
et les microfilms, sans l'accord écrit de l'IEC ou du Comité national de l'IEC du pays du demandeur. Si vous avez des
questions sur le copyright de l'IEC ou si vous désirez obtenir des droits supplémentaires sur cette publication, utilisez
les coordonnées ci-après ou contactez le Comité national de l'IEC de votre pays de résidence.

IEC Secretariat Tel.: +41 22 919 02 11
3, rue de Varembé info@iec.ch
CH-1211 Geneva 20 www.iec.ch
Switzerland
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 corrigendum or an amendment might have been published.

IEC publications search - webstore.iec.ch/advsearchform IEC Products & Services Portal - products.iec.ch
The advanced search enables to find IEC publications by a Discover our powerful search engine and read freely all the
variety of criteria (reference number, text, technical publications previews. With a subscription you will always
committee, …). It also gives information on projects, replaced have access to up to date content tailored to your needs.
and withdrawn publications.
Electropedia - www.electropedia.org
IEC Just Published - webstore.iec.ch/justpublished
The world's leading online dictionary on electrotechnology,
Stay up to date on all new IEC publications. Just Published
containing more than 22 300 terminological entries in English
details all new publications released. Available online and
and French, with equivalent terms in 19 additional languages.
once a month by email.
Also known as the International Electrotechnical Vocabulary

(IEV) online.
IEC Customer Service Centre - webstore.iec.ch/csc
If you wish to give us your feedback on this publication or
need further assistance, please contact the Customer Service
Centre: sales@iec.ch.
A propos de l'IEC
La Commission Electrotechnique Internationale (IEC) est la première organisation mondiale qui élabore et publie des
Normes internationales pour tout ce qui a trait à l'électricité, à l'électronique et aux technologies apparentées.

A propos des publications IEC
Le contenu technique des publications IEC est constamment revu. Veuillez vous assurer que vous possédez l’édition la
plus récente, un corrigendum ou amendement peut avoir été publié.

Recherche de publications IEC - IEC Products & Services Portal - products.iec.ch
webstore.iec.ch/advsearchform Découvrez notre puissant moteur de recherche et consultez
La recherche avancée permet de trouver des publications IEC gratuitement tous les aperçus des publications. Avec un
en utilisant différents critères (numéro de référence, texte, abonnement, vous aurez toujours accès à un contenu à jour
comité d’études, …). Elle donne aussi des informations sur adapté à vos besoins.
les projets et les publications remplacées ou retirées.

Electropedia - www.electropedia.org
IEC Just Published - webstore.iec.ch/justpublished
Le premier dictionnaire d'électrotechnologie en ligne au
Restez informé sur les nouvelles publications IEC. Just
monde, avec plus de 22 300 articles terminologiques en
Published détaille les nouvelles publications parues.
anglais et en français, ainsi que les termes équivalents dans
Disponible en ligne et une fois par mois par email.
19 langues additionnelles. Egalement appelé Vocabulaire

Electrotechnique International (IEV) en ligne.
Service Clients - webstore.iec.ch/csc

Si vous désirez nous donner des commentaires sur cette
publication ou si vous avez des questions contactez-nous:
sales@iec.ch.
IEC 62906-5-7 ®
Edition 1.0 2022-01
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Laser displays –
Part 5-7: Measuring methods of image quality affected by speckle for scanning

laser displays
Affichages laser –
Partie 5-7: Méthodes de mesure de la qualité d’image affectée par la tacheture

pour les affichages laser à balayage

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 31.260 ISBN 978-2-8322-1069-5

– 2 – IEC 62906-5-7:2022 © IEC 2022
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms, definitions, abbreviated terms, and letter symbols . 7
3.1 Terms and definitions . 7
3.2 Abbreviated terms . 8
3.3 Letter symbols . 9
4 Standard measuring conditions . 10
4.1 General . 10
4.2 Standard measuring environmental conditions . 10
4.3 Standard measuring dark-room conditions . 10
4.4 Standard DUT conditions . 10
4.5 Standard LMD requirements . 10
4.6 Screen requirements . 12
5 Standard measurement setup and coordinate system . 12
5.1 Direct measurement setup . 12
5.2 Diffuse reflectance standard measurement . 13
5.3 Full-screen measurement . 14
6 Measuring methods . 15
6.1 Wavelength/spectrum and photometric/colorimetric measurements . 15
6.2 Monochromatic speckle contrast and colour speckle . 17
6.2.1 General . 17
6.2.2 Noise analysis of speckle . 17
6.2.3 Measurement procedure . 18
6.3 Speckle-affected image resolution . 19
6.3.1 Grille patterns . 19
6.3.2 Contrast modulation (grille-pattern contrast) under speckle effects . 19
6.3.3 Measurement procedure . 22
6.3.4 Colour speckle and dynamic colour speckle . 23
6.4 Non-uniformity/uniformity . 25
6.4.1 General . 25
6.4.2 Measurement points . 25
6.4.3 Measuring method . 25
Annex A (informative) Spectral accuracy for keeping a specific chromaticity accuracy . 28
A.1 General . 28
A.2 Calculated example of wavelength accuracy . 28
Annex B (informative) Conventional contrast modulation (grille-pattern luminance
contrast) for displays . 29
Annex C (informative) Examples of speckle data for grille patterns . 31
Bibliography . 33

Figure 1 – Setup and coordinate system of direct illuminance measurements . 13
Figure 2 – Setup and coordinate system of diffuse reflectance standard measurements . 14
Figure 3 – Setup and coordinate system of full-screen measurements . 14

Figure 4 – Example of spectra of single-longitudinal mode RGB lasers . 15
Figure 5 – Example of spectrum of multi-longitudinal modes . 16
Figure 6 – Grille patterns in both horizontal and vertical directions. 19
Figure 7 – Measured data of speckled grille pattern and lines along the grille direction . 21
Figure 8 – Eye-diagram representation of normalized illuminance distribution of
speckle . 22
Figure 9 – Example of chromaticity distribution for the colour speckle observed in the

uniform image region (CIE 1976 plot) . 24
Figure 10 – Example of dynamic colour speckle in a period (CIE 1976 plot) . 25
Figure 11 – Non-uniformity measurement positions (rectangular pattern) . 26
Figure 12 – Non-uniformity measurement positions (grille pattern) . 27
Figure A.1 – Calculated wavelength accuracy to keep |Δu’|, |Δv’| < 0,001 . 28
Figure B.1 – Example of the measured grille pattern . 29
Figure B.2 – Example of C plot . 30
M
Figure C.1 – Example of visualized 2D-captured data for R, G, B monochromatic
speckle, and for colour speckle of colour W (white) . 31
Figure C.2 – Example of C plot under the effects of speckle . 32
M-speckle
Table 1 – Letter symbols (quantity symbols / unit symbols) . 9

– 4 – IEC 62906-5-7:2022 © IEC 2022
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
LASER DISPLAYS –
Part 5-7: Measuring methods of image quality affected
by speckle for scanning laser displays

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
...