CEN ISO/TR 9241-311:2023
(Main)Ergonomics of human-system interaction - Part 311: Application of ISO 9241-307: LCD screens for workstations (ISO/TR 9241-311:2022)
Ergonomics of human-system interaction - Part 311: Application of ISO 9241-307: LCD screens for workstations (ISO/TR 9241-311:2022)
This document provides information relating to the specification of liquid crystal display (LCD) screens at visual display workstations in indoor location, in accordance with ISO 9241-307:2008 clause 5.2. The decision guidance is limited to LCD screens, since these are typically used at workstations.
The information is intended to support managerial decision makers (e. g. procurement operators, companies’ safety committees, occupational safety and health professionals), who are responsible for the acquisition of visual displays.
Ergonomie der Mensch-System-Interaktion - Teil 311: Anwendung von ISO 9241-307: LCD-Bildschirme für Bildschirmarbeitsplätze (ISO/TR 9241-311:2022)
Ergonomie de l'interaction homme-système - Partie 311: Application de l'ISO 9241-307: Écrans LCD pour les postes de travail (ISO/TR 9241-311:2022)
Ergonomija medsebojnega vpliva človek-sistem - 311. del: Uporaba ISO 9241-307: Zasloni LCD za delovne postaje (ISO/TR 9241-311:2022)
Ta dokument vsebuje informacije v zvezi s specifikacijo zaslonov s tekočimi kristali (LCD) na delovnih postajah za vizualni prikaz, nameščenih v notranjih prostorih, v skladu s točko 5.2 standarda ISO 9241-307:2008. Ta smernica o odločitvi je omejena na zaslone s tekočimi kristali, ker se ti običajno uporabljajo na delovnih postajah.
Informacije so namenjene za podporo poslovodnih odločevalcev (npr. upravljavci javnih naročil, varnostni odbori podjetij, strokovnjaki za zdravje in varnost pri delu), ki so odgovorni za prevzem vizualnih prikazovalnikov.
General Information
Standards Content (Sample)
SLOVENSKI STANDARD
SIST-TP CEN ISO/TR 9241-311:2023
01-maj-2023
Ergonomija medsebojnega vpliva človek-sistem - 311. del: Uporaba ISO 9241-307:
Zasloni LCD za delovne postaje (ISO/TR 9241-311:2022)
Ergonomics of human-system interaction - Part 311: Application of ISO 9241-307: LCD
screens for workstations (ISO/TR 9241-311:2022)
Ergonomie der Mensch-System-Interaktion - Teil 311: Anwendung von ISO 9241-307:
LCD-Bildschirme für Bildschirmarbeitsplätze (ISO/TR 9241-311:2022)
Ergonomie de l'interaction homme-système - Partie 311: Application de l'ISO 9241-307:
Écrans LCD pour les postes de travail (ISO/TR 9241-311:2022)
Ta slovenski standard je istoveten z: CEN ISO/TR 9241-311:2023
ICS:
13.180 Ergonomija Ergonomics
35.180 Terminalska in druga IT Terminal and other
periferna oprema IT peripheral equipment
SIST-TP CEN ISO/TR 9241-311:2023 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
---------------------- Page: 1 ----------------------
SIST-TP CEN ISO/TR 9241-311:2023
CEN ISO/TR 9241-311
TECHNICAL REPORT
RAPPORT TECHNIQUE
February 2023
TECHNISCHER REPORT
ICS 13.180; 35.180
English Version
Ergonomics of human-system interaction - Part 311:
Application of ISO 9241-307: LCD screens for workstations
(ISO/TR 9241-311:2022)
Ergonomie de l'interaction homme-système - Partie Ergonomie der Mensch-System-Interaktion - Teil 311:
311: Application de l'ISO 9241-307: Écrans LCD pour Anwendung von ISO 9241-307: LCD-Bildschirme für
les postes de travail (ISO/TR 9241-311:2022) Bildschirmarbeitsplätze (ISO/TR 9241-311:2022)
This Technical Report was approved by CEN on 21 February 2023. It has been drawn up by the Technical Committee CEN/TC
122.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2023 CEN All rights of exploitation in any form and by any means reserved Ref. No. CEN ISO/TR 9241-311:2023 E
worldwide for CEN national Members.
---------------------- Page: 2 ----------------------
SIST-TP CEN ISO/TR 9241-311:2023
CEN ISO/TR 9241-311:2023 (E)
Contents Page
European foreword . 3
2
---------------------- Page: 3 ----------------------
SIST-TP CEN ISO/TR 9241-311:2023
CEN ISO/TR 9241-311:2023 (E)
European foreword
The text of ISO/TR 9241-311:2022 has been prepared by Technical Committee ISO/TC 159
"Ergonomics” of the International Organization for Standardization (ISO) and has been taken over as
CEN ISO/TR 9241-311:2023 by Technical Committee CEN/TC 122 “Ergonomics” the secretariat of
which is held by DIN.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
Any feedback and questions on this document should be directed to the users’ national standards body.
A complete listing of these bodies can be found on the CEN website.
Endorsement notice
The text of ISO/TR 9241-311:2022 has been approved by CEN as CEN ISO/TR 9241-311:2023 without
any modification.
3
---------------------- Page: 4 ----------------------
SIST-TP CEN ISO/TR 9241-311:2023
---------------------- Page: 5 ----------------------
SIST-TP CEN ISO/TR 9241-311:2023
TECHNICAL ISO/TR
REPORT 9241-311
First edition
2022-04
Ergonomics of human-system
interaction —
Part 311:
Application of ISO 9241-307: LCD
screens for workstations
Reference number
ISO/TR 9241-311:2022(E)
© ISO 2022
---------------------- Page: 6 ----------------------
SIST-TP CEN ISO/TR 9241-311:2023
ISO/TR 9241-311:2022(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2022
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii
© ISO 2022 – All rights reserved
---------------------- Page: 7 ----------------------
SIST-TP CEN ISO/TR 9241-311:2023
ISO/TR 9241-311:2022(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Classification, profiles and screen selection . 5
4.1 General . 5
4.2 Profiles . 8
4.2.1 General . 8
4.2.2 Profile No. 1 . 9
4.2.3 Profile No. 2 . 9
4.2.4 Profile No. 3 . 9
4.2.5 Profile No. 4 . 10
4.3 Comparison of the profiles. 10
Bibliography .14
iii
© ISO 2022 – All rights reserved
---------------------- Page: 8 ----------------------
SIST-TP CEN ISO/TR 9241-311:2023
ISO/TR 9241-311:2022(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to
the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see
www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 159, Ergonomics, Subcommittee SC 4,
Ergonomics of human-system interaction.
This first edition cancels and replaces ISO 9241-3:1992.
A list of all parts in the ISO 9241 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
iv
© ISO 2022 – All rights reserved
---------------------- Page: 9 ----------------------
SIST-TP CEN ISO/TR 9241-311:2023
ISO/TR 9241-311:2022(E)
Introduction
1) 1) 1) 1)
The ISO 9241-30x family of standards has replaced ISO 9241-3 , ISO 9241-7 , ISO 9241-8 , ISO 13406-1
1)
and ISO 13406-2 . The overall goal of the restructuring was to design a modular standard enabling an
easy way of adding new intended contexts of use, new measurement methods or new technologies in
the ISO 9241-30x family of standards.
The ISO 9241-30x family of standards consists of seven individual standards. Table 1 gives an overview
(for details see the standards themselves).
This document refers to ISO 9241-307. It helps explain the transition from the earlier structure of the
related standards to the current structure. It will be revised or withdrawn following the revision of
ISO 9241-307.
Table 1 — Overview of the ISO 9241-30x family of standards
Part of ISO 9241-30x Title and explanation
ISO 9241-300 Introduction to electronic visual display requirements
— This part introduces the ISO 9241-30x family of standards and explains the
modular structure.
ISO 9241-302 Terminology for electronic visual displays
— This part explains the terms and definitions used in the series.
ISO 9241-303 Requirements for electronic visual displays
— This part establishes fundamental image-quality requirements on a generic
basis. For assessing its requirements, a testing method is needed regarding its
technology, task and environment.
ISO 9241-304 User performance test methods for electronic visual displays
— This part provides guidance for assessing the visual ergonomics of display
technologies with user performance test methods.
ISO 9241-305 Optical laboratory test methods for electronic visual displays
— This part contains test methods for measurement of the requirements given in
ISO 9241-303.
ISO 9241-306 Field assessment methods for electronic visual displays
— This part describes simplified optical, geometrical and visual assessment
methods that can be used for on-site measurements at visual display
a
workstations.
ISO 9241-307 Analysis and compliance test methods for electronic visual displays
— This part establishes test methods for the analysis of a variety of visual display
technologies, tasks and environments. It refers to the general requirements
given in ISO 9241-303 and test methods given in ISO 9241-305 for assessment of
conformity for different (display-) technologies and the anticipated contexts of
use.
a
ISO test charts for the visual assessment of the display output by yes/no question are available from:
https://standards.iso.org/iso/9241/306/ed-2/index.html
https://standards.iso.org/iso/9241/306/ed-2/AE09/AE09F0PX.PDF (achromatic, 2 MB)
https://standards.iso.org/iso/9241/306/ed-2/AE18/AE18F0PX.PDF (chromatic, 14 MB)
1) Cancelled and replaced by ISO 9241-302, ISO 9241-303, ISO 9241-304, ISO 9241-305, ISO 9241-307
and ISO 9241-311.
v
© ISO 2022 – All rights reserved
---------------------- Page: 10 ----------------------
SIST-TP CEN ISO/TR 9241-311:2023
---------------------- Page: 11 ----------------------
SIST-TP CEN ISO/TR 9241-311:2023
TECHNICAL REPORT ISO/TR 9241-311:2022(E)
Ergonomics of human-system interaction —
Part 311:
Application of ISO 9241-307: LCD screens for workstations
1 Scope
This document provides information relating to the specification of liquid crystal display (LCD) screens
at visual display workstations in indoor locations, in accordance with ISO 9241-307:2008, 5.2. The
information is limited to LCD screens, since these are typically used at workstations.
The information is intended to support managerial decision makers (e.g. procurement operators,
companies’ safety committees, occupational safety and health professionals) who are responsible for
the acquisition of visual displays.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 9241-302:2008, Ergonomics of human-system interaction — Part 302: Terminology for electronic
visual displays
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 9241-302 and the following
apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
artificial information
visualization of objects and scenes that do not have originals in our world in monochrome (including
achromatic) and/or multicolour (including full-colour) presentation
EXAMPLE Text (i.e. alphanumeric characters), graphical signs, symbols.
Note 1 to entry: See ISO 9241-307:2008, Table 38.
3.2
reality information
imaging of objects and scenes that do have existing originals in our world in monochrome (including
achromatic) and/or multicolour (including full-colour) presentation
EXAMPLE Faces, people, landscapes.
Note 1 to entry: See ISO 9241-307:2008, Table 38.
1
© ISO 2022 – All rights reserved
---------------------- Page: 12 ----------------------
SIST-TP CEN ISO/TR 9241-311:2023
ISO/TR 9241-311:2022(E)
3.3
design viewing direction
specific direction from which the visual display is intended to be viewed
Note 1 to entry: See ISO 9241-307:2008, Table 38.
Note 2 to entry: Reality information is not considered.
3.4
design screen illuminance
specific maximum illuminance on the screen caused by ambient illumination
Note 1 to entry: See ISO 9241-307:2008, Table 38.
3.5
luminance balance
ratio between the luminances of the displayed image and its adjacent surround or sequentially viewed
surfaces
[SOURCE: ISO 9241-302:2008, 3.4.18]
3.6
colour non-uniformity
change of a colour in the active area of the screen
Note 1 to entry: See ISO 9241-303:2011, 5.4.3.
Note 2 to entry: Variation considers lateral and directional changes.
3.7
contrast non-uniformity
unintended variations in contrast (luminance ratio) in the active area of the screen
Note 1 to entry: There are three different forms of contrast non-uniformity:
— variation in area average luminance contrast from the centre of a display to the edge of any portion thereof;
— variation of the peak contrast of character elements (dots or strokes) at different locations of the screen;
— variation of the peak contrast of character elements (dots or strokes) within a character.
Note 2 to entry: See ISO 9241-303:2011, 5.4.4.
3.8
visual artefacts
Moiré effects
regular image superimposed on the intended image
Note 1 to entry: Moiré effects can appear as ripples, waves and intensity variations.
Note 2 to entry: Moiré effects are disturbing information.
Note 3 to entry: See ISO 9241-303:2011, 5.4.9.
3.9
unintended depth effects
perception of depth by combination of spectrally extreme colours
EXAMPLE Combination of red and blue.
Note 1 to entry: See ISO 9241-303:2011, 5.4.12.
2
© ISO 2022 – All rights reserved
---------------------- Page: 13 ----------------------
SIST-TP CEN ISO/TR 9241-311:2023
ISO/TR 9241-311:2022(E)
3.10
luminance contrast
ratio between the higher luminance, L , and lower luminance, L , that defines the feature to be detected
H L
Note 1 to entry: ISO 9241-303:2011, ISO 9241-305:2008 and ISO 9241-307:2008 use luminance contrast measured
by contrast modulation or measured by contrast ratio.
[SOURCE: ISO 9241-302:2008, 3.1.7, modified — Notes to entry replaced.]
3.11
image polarity
relationship between background brightness and image brightness
Note 1 to entry: The presentation of brighter characters on a darker background is designated as negative
polarity, and the presentation of darker characters on a brighter background is designated as positive polarity.
[SOURCE: ISO 9241-302:2008, 3.4.15]
3.12
character format
number of horizontal and vertical elements of a character
Note 1 to entry: An element is understood to be a pixel, which is the smallest element that is capable of generating
the full intended functionality (e.g. colour and grey scale) of the display.
[SOURCE: ISO 9241-302:2008, 3.6.5, modified — definition revised and notes to entry replaced.]
3.13
luminance coding
information presented by temporally independent differences in image luminances
EXAMPLE Information highlighted by differences in luminance.
Note 1 to entry: Absolute luminance coding is understood to be information presented where the only dimension
that is used for visual differentiation is the difference in image luminances (see ISO 9241-302:2008, 3.4.1).
[SOURCE: ISO 9241-302:2008, 3.4.19, modified — example and Note 1 to entry added.]
3.14
blink coding
information presented by temporal luminance variations in images
[SOURCE: ISO 9241-302:2008, 3.3.8]
3.15
colour coding
information coding by using distinguishable colours
Note 1 to entry: See ISO 9241-303:2011, 5.6.4.
3.16
geometrical coding
information coding by using different geometrical shapes
EXAMPLE Use of graphical symbols (e.g. triangles and circles for distinguishing curves in diagrams).
Note 1 to entry: See ISO 9241-303:2011, 5.6.5.
3.17
object size
visual angle required for objects to be recognizable
Note 1 to entry: See ISO 9241-303:2011, 5.7.2.
3
© ISO 2022 – All rights reserved
---------------------- Page: 14 ----------------------
SIST-TP CEN ISO/TR 9241-311:2023
ISO/TR 9241-311:2022(E)
Note 2 to entry: Object size can be monochrome or multicolour.
3.18
contrast for object legibility
contrast required for objects to be recognizable
Note 1 to entry: See ISO 9241-303:2011, 5.7.3.
3.19
colour considerations for graphics
summary of requirements for coloured symbols or characters
Note 1 to entry: A default colour set with distinguishable colours is required to be available. Characters and
′
symbols need to be presented with a visual angle of at least 20 of arc at the design viewing distance (2,9 mm
height of character or symbol at 500 mm viewing distance). Where accurate colour identification of an isolated
′
image such as a character or symbol is required, the image should be at least 30 of arc at the design viewing
′
distance, preferably 45 of arc.
Note 2 to entry: See ISO 9241-303:2011, 5.7.4.
3.20
surrounding image effects
background
effects with reference to the discriminability of image background and image foreground
Note 1 to entry: For colours to be discriminable and identifiable, coloured foreground images should be used on
achromatic background and vice versa.
Note 2 to entry: See ISO 9241-303:2011, 5.7.5.
3.21
colour gamut
number of colours used by an application as a percentage of all colours of the chromaticity diagram
Note 1 to entry: Depending on the application for office tasks (artificial information), a minimum of six and a
maximum of 11 discriminable colours should be provided.
Note 2 to entry: See ISO 9241-303:2011, 5.7.6 and 5.8.2.1 and ISO 9241-307:2008, Table 83.
3.22
reference white
specified reference for the white achromatic stimulus displayed on the monitor
Note 1 to entry: See ISO 9241-307:2008, Table 83.
3.23
electro-optical transfer function
function describing the relationship between input signal of a display and the displayed luminance
Note 1 to entry: See ISO 9241-307:2008, Table 86.
3.24
grey scale
greys displayed by more than two luminance levels
Note 1 to entry: See ISO 9241-307:2008, Table 86.
3.25
image formation time
time that is needed by the display to change the image from one luminance state to another luminance
state and vice versa
[SOURCE: ISO 9241-302:2008, 3.4.14, modified — definition revised; example and note to entry deleted.]
4
© ISO 2022 – All rights reserved
---------------------- Page: 15 ----------------------
SIST-TP CEN ISO/TR 9241-311:2023
ISO/TR 9241-311:2022(E)
3.26
spatial resolution
display resolution in horizontal pixels times vertical pixels
Note 1 to entry: See ISO 9241-303:2011, 5.8.6.
3.27
fill factor
fraction of the total pixel area geometrically available that can be altered to display information
Note 1 to entry: For discrete-pixel displays, the outer boundary of all the pixels defines the active area. Between
the pixels and subpixels are gaps that structurally support or define the pixel. The ratio of the active area minus
the area of the gaps to the active area is the fill factor.
[SOURCE: ISO 9241-302:2008, 3.4.10]
3.28
pixel density
number of pixels per dimension
EXAMPLE ppi = pixels per inch.
Note 1 to entry: The dimension can be a length measured in centimetres or inches, or an angle measured in
degrees at the design viewing distance.
Note 2 to entry: See ISO 9241-303:2011, 5.8.7, 5.8.8 and ISO 9241-307:2008, Table 91.
4 Classification, profiles and screen selection
4.1 General
In combination with ISO 9241-303 and ISO 9241-305, ISO 9241-307 forms the basis for conformity
assessment of LCD screens and is therefore considered to be the relevant standard for the acquisition
and specification of screens.
Whereas ISO 9241-3, ISO 9241-7, ISO 9241-8, ISO 13406-1 and ISO 13406-2 mainly took visual display
workstations into account, the scope of ISO 9241-307 was broadened and additional technologies were
considered.
The broad scope of ISO 9241-307 includes the following changes:
— consideration of illuminance between 50 lx and 1 500 lx;
— consideration of the luminance of an extended light source that can reflect in the screen, with higher
2 2
values of 300 cd/m or 500 cd/m ;
2)
— integration of CIE-illuminants A, F11 and F12 ;
— discrimination between “artificial information” and “reality information” regarding content and
perception.
ISO 9241-307 considers the following technologies:
— Cathode ray tube (CRT) displays;
— emissive flat-panel LCD;
— plasma display panels;
— front-screen projection visual displays;
2) CIE standard illuminant A (ISO 11664-2:2007/CIE S 014-2:2006), CIE illuminants FL11 and FL12 (CIE 018:2018)
5
© ISO 2022 – All rights reserved
---------------------- Page: 16 ----------------------
SIST-TP CEN ISO/TR 9241-311:2023
ISO/TR 9241-311:2022(E)
— emissive, reflective and transflective LCDs for hand-held devices.
Extending the scope led to discontinuation of the former classification (e.g. of the hitherto known
reflection classes according to ISO 13406-2. In ISO 9241-307 this is replaced by the corresponding
luminances. Comparability with the former reflection classes is guaranteed. Table 2 shows the
correlation of the former reflection classes to the luminances.
Table 2 — Comparison of reflection classes
Luminance of directional reflected Example for environment
Reflection class according to
2
light sources [cd/m ] according to ISO 9241-307 (ISO 13406-2, ISO
ISO 13406-2
ISO 9241-307 9241-7)
For specialized use with very strin-
a
N/A L = 500 and L = N/A gent level on robustness against
REF, EXT REF, SML
b
light
For general use in offices near
c
N/A L = 300 and L = N/A windows with stringent level on
REF, EXT REF, SML
d
robustness against light
e
I L = 200 and L = 2 000 General office use
REF, EXT REF, SML
For most but not all office environ-
II L = 200 or L = 2 000
REF, EXT REF, SML f
ments
Requires a specially controlled
III L = 200 or L = 125
REF, EXT REF, SML g
luminous environment
Key
N/A not applicable
REF, EXT large reference aperture source
REF, SML small reference aperture source
a 2
L = 5 000 cd/m .
REF, SML
b
Workstations with a very high illumination level.
c 2
L = 3 000 cd/m .
REF, SML
d
Workstations near windows, sun protection used only slightly.
e
Visual displays of this type can be used in any office environment. Workstations near windows, sun protection used in
good time.
f
Visual displays of this type can cause disturbing reflections if used in environments with no ideal lighting or positioned
near windows. Workstations far from windows with low illumination level.
g
Visual displays of this type cause greatly disturbing reflections, so these devices cannot be used for office work under
normal office environments. These disturbances can only be handled by complete diffuse lighting, which, however, is hardly
realizable from a technical point of view. Furthermore, the reflection of bright surfaces in the screens (e.g. walls, windows)
needs to be avoided. Workstations far from windows with completely diffuse lighting and without bright surfaces (e.g.
walls, windows) that can be reflected in the screen.
Additional changes or innovations in classification have been made in, for example, colour non-
uniformity and pixel fault classification. For “reality information”, higher levels of image quality are
defined.
In detail, Table 3 shows changes within the classification of the colour non-uniformity.
6
© ISO 2022 – All rights reserved
---------------------- Page: 17 ----------------------
SIST-TP CEN ISO/TR 9241-311:2023
ISO/TR 9241-311:2022(E)
Table 3 — Comparison of the classification of colour non-uniformity
Class according to Classification according to ISO 9241-
The classification is fulfilled…
ISO 13406-2 307
a
III High class chromaticity uniformity in a … for all colour combinations
viewing cone with a single visual display
R and/or G and/or B = 100 %
R and G and B = 75 %
R and/or G and/or B = 50 %
a
III Medium class chromaticity uniformity in … for all colour combinations
a viewing cone with a single visual display
R and/or G and/or B = 100 %
R = G = B = 75 %
III Low class chromaticity uniformity in a … only for primary colours
viewing cone with a single visual display
R = 100 %, G = 100 %, B = 100 %
IV Low class chromaticity uniformity in a … for all colours in a restricted viewing cone
restricted viewing cone
a
Pigment content of red, green and blue for generating mixed colours or primary colour.
The pixel fault classes have been changed as shown in Table 4 and Table 5, which give a (simplified)
comparison between the possible pixel fault classes of ISO 9241-307 and the former classifications
according to ISO 13406-2 for all typical screen sizes found at workstations.
Table 4 — Comparison of pixel fault classes
Classification ISO 9241-307 pixel Type 1 Type 2 Type 3
according to fault class Class
Pixel
(Pixel permanently (Pixel permanently (Subpixel perma-
ISO 13406-2
bright) dark) nently bright/dark)
I 0 0 0 0/0
— I 1 1 2/1
II II 2 2 5/0
III III 5 15 50/0
IV IV 50 150 500/0
NOTE 1 Numerical data: maximum number of faults per type and per million pixels.
NOTE 2 ISO 13406-2 had not differentiated between “permanently bright”/”permanently dark” subpixel faults. This is new
with ISO 9241-307.
Table 5 — Comparison of the pixel fault classes – Continuation
Type 3 Accumu-
Type 1 (Pixel Type 2 (Pixel
ISO 9241- lation of Accumulation
permanently permanently
Permanently Permanently
307 Class Type 1 or of Type 3
Pixel
bright) dark)
bright dark
Type 2
0 0 0 0 0 0 0
I 1 1 2 1 0 0
1 1 1 3 0 0
1 1 0 5 0 0
NOTE 1 Numerical data: maximum number of faults per type and per million pixels.
NOTE 2 The classification is made by declaring the pixel fault class and the counter n . In pixe
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.