SIST EN ISO 15008:2009

Road vehicles - Ergonomic aspects of transport information and control systems - Specifications and test procedures for invehicle visual presentation (ISO 15008:2009)

This International Standard gives minimum  specifications for the image quality and legibility  of displays containing dynamic (changeable)  visual information presented to the driver of a  road vehicle by on-board transport information  and control systems (TICS) used while the  vehicle is in motion. These specifications are  intended to be independent of display  technologies, while reference to test methods  and measurements for assessing compliance  with them have been included where necessary.  This International Standard is applicable to  mainly perceptual, and some basic cognitive,  components of the visual information: these  include character legibility and colour  recognition. It is not applicable to other factors  affecting performance and comfort such as  coding, format and dialogue characteristics, or  to displays using - redundantly presented  information (only primary information shall meet  this Standard); ? characters presented as a part  of a symbol or pictorial information; -  superimposed information on the external field  (e.g. head-up displays); - pictorial images (e.g.  rear view camera); - maps and topographic  representations (e.g. those for setting navigation  systems); or - quasi static information.

Straßenfahrzeuge - Ergonomische Aspekte von Fahrerinformations- und Assistenzsystemen - Anforderungen und Bewertungsmethoden der visuellen Informationsdarstellung im Fahrzeug (ISO 15008:2009)

Diese Internationale Norm legt Mindestanforderungen an die Bildqualität und Lesbarkeit von Anzeigen, für die
Darstellung von dynamischen (sich ändernden) visuellen Informationen fest, die dem Fahrer eines
Straßenfahrzeuges von einem internen Fahrerinformations- und Assistenzsystem (en: Transport Information
and Control System, TICS) während der Fahrt so bereitgestellt werden, dass diese auf der Anzeige lesbar
sind. Diese Anforderungen sollen unabhängig von speziellen Anzeige-Technologien gelten. Verweisungen auf
Test- und Messmethoden sind dort eingefügt worden, wo sie zur Überprüfung und Einhaltung der
Anforderungen notwendig sind.
Diese Internationale Norm betrifft hauptsächlich Wahrnehmungskomponenten und einige grundlegende kognitive
Komponenten der visuellen Information; diese schließen Lesbarkeit von Zeichen und Farberkennung ein. Sie ist
nicht anwendbar auf andere Faktoren, welche die Wahrnehmungsleistung und den Komfort beeinflussen, wie
z. B. Kodierung, Format und Dialog-Formen, oder auf Anzeigesysteme, die
⎯ Zeichen verwenden, die Teil eines Symbols oder einer bildhaften Information sind,
⎯ dem externen Sichtfeld überlagerte Informationen enthalten (z. B. Head-up Displays),
⎯ bildhafte Informationen darstellen (z. B. Rückfahrkamera),
⎯ Karten und topographische Darstellungen anzeigen (z. B. bei Navigationssystemen),
⎯ quasi-statische Informationen anzeigen.

Véhicules routiers - Aspects ergonomiques des systèmes d'information et de commande du transport - Spécifications et méthodes d'essai pour la présentation visuelle à bord du véhicule (ISO 15008:2009)

L'ISO 15008:2009 spécifie les exigences minimales de qualité d'image et de lisibilité d'image des afficheurs qui fournissent au conducteur d'un routier des informations visuelles dynamiques (changeantes) issues des systèmes de commande et d'information des transports (TICS) embarqués utilisables pendant que le véhicule est en mouvement. Ces exigences sont indépendantes des technologies d'affichage utilisées, alors que les méthodes d'essai et les mesures qui permettent d'évaluer la conformité aux spécifications sont indiquées si nécessaire.
L'ISO 15008:2009 est applicable principalement aux composantes perceptives et à certaines composantes cognitives fondamentales de l'information visuelle, y compris la lisibilité des caractères et la reconnaissance des couleurs. Elle n'est pas applicable à d'autres facteurs affectant les performances et le confort, tels que le codage, le format et les caractéristiques du dialogue, ni aux afficheurs utilisant
des caractères présentés comme une partie d'un symbole ou d'information graphique,
des informations superposées à la scène extérieure au véhicule (par exemple affichages tête haute),
des images graphiques (par exemple d'une caméra de vue arrière),
des cartes et des représentations topographiques (par exemple, celles pour régler les systèmes de navigation), ou
des informations quasi statiques.

Cestna vozila - Ergonomski vidiki transportnih informacij in kontrolnih sistemov - Specifikacije in postopki preskušanja za vizualno predstavitev v vozilu (ISO 15008:2009)

General Information

• Status: Withdrawn
• Publication Date: 04-Mar-2009
• Withdrawal Date: 04-Sep-2017
• ICS: 13.180 - Ergonomics
• ICS: 43.040.15 - Car informatics. On board computer systems
• Technical Committee: ITC - Information technology
• Current Stage: 9900 - Withdrawal (Adopted Project)
• Start Date: 05-Sep-2017
• Due Date: 28-Sep-2017
• Completion Date: 05-Sep-2017
• Ref Project: EN ISO 15008:2009 - Road vehicles - Ergonomic aspects of transport information and control systems - Specifications and test procedures for in-vehicle visual presentation (ISO 15008:2009)

Relations

• Replaced By: SIST EN ISO 15008:2017 - Road vehicles - Ergonomic aspects of transport information and control systems - Specifications and test procedures for in-vehicle visual presentation (ISO 15008:2017)
• Effective Date: 22-Mar-2017
• Replaces: SIST EN ISO 15008:2003 - Road vehicles - Ergonomic aspects of transport information and control systems - Specifications and compliance procedures for in-vehicle visual presentation (ISO 15008:2003)
• Effective Date: 01-Apr-2009

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN ISO 15008:2009
01-april-2009
1DGRPHãþD
SIST EN ISO 15008:2003
Cestna vozila - Ergonomski vidiki transportnih informacij in kontrolnih sistemov -
Specifikacije in postopki preskušanja za vizualno predstavitev v vozilu (ISO
15008:2009)
Road vehicles - Ergonomic aspects of transport information and control systems -
Specifications and test procedures for invehicle visual presentation (ISO 15008:2009)
Véhicules routiers - Aspects ergonomiques des systèmes d'information et de commande
du transport - Spécifications et méthodes d'essai pour la présentation visuelle à bord du
véhicule (ISO 15008:2009)
Ta slovenski standard je istoveten z: EN ISO 15008:2009
ICS:
13.180 Ergonomija Ergonomics
43.040.15 $YWRPRELOVNDLQIRUPDWLND Car informatics. On board
9JUDMHQLUDþXQDOQLãNLVLVWHPL computer systems
SIST EN ISO 15008:2009 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 15008:2009

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SIST EN ISO 15008:2009
EUROPEAN STANDARD
EN ISO 15008
NORME EUROPÉENNE
EUROPÄISCHE NORM
February 2009
ICS 13.180; 43.040.15 Supersedes EN ISO 15008:2003
English Version
Road vehicles - Ergonomic aspects of transport information and
control systems - Specifications and test procedures for in-
vehicle visual presentation (ISO 15008:2009)
Véhicules routiers - Aspects ergonomiques des systèmes
d'information et de commande du transport - Spécifications
et méthodes d'essai pour la présentation visuelle à bord du
véhicule (ISO 15008:2009)
This European Standard was approved by CEN on 21 January 2009.
CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European
Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national
standards may be obtained on application to the CEN Management Centre or to any CEN member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as the
official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,
Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2009 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 15008:2009: E
worldwide for CEN national Members.

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SIST EN ISO 15008:2009
EN ISO 15008:2009 (E)
Contents Page
Foreword .3

2

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SIST EN ISO 15008:2009
EN ISO 15008:2009 (E)
Foreword
This document (EN ISO 15008:2009) has been prepared by Technical Committee ISO/TC 22 "Road vehicles"
in collaboration with Technical Committee CEN/TC 278 "Road transport and traffic telematics", the secretariat
of which is held by NEN.
This European Standard shall be given the status of a national standard, either by publication of an identical
text or by endorsement, at the latest by August 2009, and conflicting national standards shall be withdrawn at
the latest by August 2009.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN ISO 15008:2003.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Cyprus, Czech
Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain,
Sweden, Switzerland and the United Kingdom.
Endorsement notice
The text of ISO 15008:2009 has been approved by CEN as a EN ISO 15008:2009 without any modification.

3

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SIST EN ISO 15008:2009

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SIST EN ISO 15008:2009

INTERNATIONAL ISO
STANDARD 15008
Second edition
2009-02-15

Road vehicles — Ergonomic aspects of
transport information and control
systems — Specifications and test
procedures for in-vehicle visual
presentation
Véhicules routiers — Aspects ergonomiques des systèmes
d'information et de commande du transport — Spécifications et
méthodes d'essai pour la présentation visuelle à bord du véhicule




Reference number
ISO 15008:2009(E)
©
ISO 2009

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SIST EN ISO 15008:2009
ISO 15008:2009(E)
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©  ISO 2009
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 ISO at the address below or
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Published in Switzerland

ii © ISO 2009 – All rights reserved

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SIST EN ISO 15008:2009
ISO 15008:2009(E)
Contents Page
Foreword. iv
Introduction . v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions. 1
4 Requirements and measurement methods. 4
4.1 General. 4
4.2 Design viewing position and illumination range . 4
4.3 Display illumination, minimum contrast, luminance and polarity . 7
4.4 Colour combinations. 10
4.5 Alphanumerical character dimensions.10
4.6 Pixel matrix character format . 11
4.7 Reflections and glare. 13
4.8 Characteristics of presentation. 13
4.9 Redundant information displays. 14
Annex A (normative) Definition and measurement of character dimensions. 15
Annex B (informative) Colour combinations . 17
Bibliography . 18

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SIST EN ISO 15008:2009
ISO 15008:2009(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.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
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.
ISO 15008 was prepared by Technical Committee ISO/TC 22, Road vehicles, Subcommittee SC 13,
Ergonomics applicable to road vehicles.
This second edition cancels and replaces the first edition (ISO 15008:2003), which has been technically
revised.
iv © ISO 2009 – All rights reserved

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SIST EN ISO 15008:2009
ISO 15008:2009(E)
Introduction
Driver and vehicle form an integrated system that includes the environment, the primary vehicle controls, the
instrumentation and the transport information and control systems (TICS). The task of driving, as well as
human capabilities and limitations, are other important factors in the performance of this system.
TICS are intended to support drivers in their primary task, and it is therefore expected that the overall
workload of the driver will not be negatively influenced by the use of TICS, while performance and comfort are
increased.
The visual characteristics of display systems are only one set of factors influencing this process. They
therefore need to be considered, along with human capabilities, in connection with the other elements of the
driving environment.
Visual specifications fall within a wide range of environmental conditions and constitute only one necessary
condition for adequate performance, comfort and workload. They refer to the relevant range of illumination
conditions and to the location of the display with respect to the driver.
The following substantial changes have been made compared with the first edition of this International
Standard:
⎯ extension of the scope,
⎯ updating of normative and bibliographic references, and terms and definitions,
⎯ clarification of design viewing positions,
⎯ referencing of contrast measurement methods and angles to SAE J1757/1:2007,
⎯ changing of illumination ranges; addition of twilight condition,
⎯ inclusion of outlined characters,
⎯ exclusion of colour contrast,
⎯ changing of minimum character heights,
⎯ inclusion of Chinese and Japanese characters, and
⎯ clarification of character dimension specifications.


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SIST EN ISO 15008:2009

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SIST EN ISO 15008:2009
INTERNATIONAL STANDARD ISO 15008:2009(E)

Road vehicles — Ergonomic aspects of transport information
and control systems — Specifications and test procedures for
in-vehicle visual presentation
1 Scope
This International Standard specifies minimum requirements for the image quality and legibility of displays
containing dynamic (changeable) visual information presented to the driver of a road vehicle by on-board
transport information and control systems (TICS) used while the vehicle is in motion. These requirements are
intended to be independent of display technologies, while reference to test methods and measurements for
assessing compliance with them have been included where necessary.
This International Standard is applicable to mainly perceptual, and some basic cognitive, components of the visual
information, including character legibility and colour recognition. It is not applicable to other factors affecting
performance and comfort, such as coding, format and dialogue characteristics, or to displays using
⎯ characters presented as a part of a symbol or pictorial information,
⎯ superimposed information on the external field (e.g. head-up displays),
⎯ pictorial images (e.g. rear view camera),
⎯ maps and topographic representations (e.g. those for setting navigation systems), or
⎯ quasi-static information.
2 Normative references
The following referenced documents are indispensable for the application 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 4513, Road vehicles — Visibility — Method for establishment of eyellipses for driver’s eye location
CIE 17.4:1987, International lighting vocabulary
CIE 85:1989, Solar spectral irradiance
SAE J1757/1:2007, Standard Metrology for Vehicular Displays
3 Terms and definitions
For the purposes of this document, the terms and definitions given in CIE 17.4:1987 and the following apply.
3.1
adaptation
adjustment of the eye’s sensitivity to the brightness of the observed visual field
NOTE Dark adaptation occurs at a slower rate than does light adaptation.
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SIST EN ISO 15008:2009
ISO 15008:2009(E)
3.2
blink
intended periodic variation of the luminance of a light or visual information, normally from “OFF” to a given
value, typically used for attracting attention
NOTE Terms and definitions related to photometric quantities (e.g. illuminance, luminance, luminance contrast and
saturation) are given in CIE 17.4:1987.
3.3
brightness
subjective attribute of light sensation by which a stimulus appears to be more or less intense or to emit more
or less light
3.4
critical specular line
CSL
line from the centre of the display to the centre of the eyellipse
3.5
chromatic
having hue or being coloured, appearing different in quality from a neutral grey having the same brightness
NOTE It is related to the colour properties of a visual stimulus.
3.6
contrast
C
ratio between the difference of the luminance, L , of an area in its “bright” state (e.g. the strokes of a
high
character in the case of negative polarity) minus the luminance, L , of the same area in its “dark” state and
low
the luminance L
low
LL−
high low
NOTE 1 C=
L
low
NOTE 2 Terms and definitions related to photometric quantities (e.g. illuminance, luminance, luminance contrast and
saturation) are given in CIE 17.4:1987.
3.7
contrast ratio
R
C
ratio between the luminance L and the luminance L
high low
L
high
NOTE 1 R =
C
L
low
NOTE 2 Terms and definitions related to photometric quantities (e.g. illuminance, luminance, luminance contrast and
saturation) are given in CIE 17.4:1987.
3.8
cyclopean eyellipse
elliptical volume combining the left and the right eyellipse of the driver into one single volume located in the
centre between them
3.9
day condition
condition with diffuse ambient light
2 © ISO 2009 – All rights reserved

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SIST EN ISO 15008:2009
ISO 15008:2009(E)
3.10
direct sunlight condition
condition under which the viewing conditions are mainly influenced by direct light from the sun on the display
surface
3.11
dynamic information
information that has more than two stages of change
3.12
eyellipse
elliptical shape of the driver eye range, as defined in ISO 4513
NOTE 1 See definition of 95th percentile eyellipse in ISO 4513.
NOTE 2 It is the contraction of the words “eye” and “ellipse”.
3.13
flicker
unintended perceived temporal variation of the brightness of a visual stimulus, usually generated by refresh
process of the display content or by variation of the luminance of the backlight
NOTE Terms and definitions related to photometric quantities (e.g. illuminance, luminance, luminance contrast and
saturation) are given in CIE 17.4:1987.
3.14
disability glare
dazzling or disabling effect produced by a bright light
NOTE This is a retinal effect, primarily caused by light scatter in the eye, which produces a luminous veil over the
retinal image and thus reduces contrast.
3.15
discomfort glare
distracting or disrupting effect of bright point sources in the field of view
NOTE This is a perceptual effect, interfering with visual attention and selection.
3.16
jitter
unintended periodic movement of an image or parts of it
3.17
legibility
visual properties of a character or graphics representation that determine the ease with which it can be
recognized
3.18
map
representation on plane surface of the features of a connected part of the earth surface (especially of the road
and traffic environment), shown in their representative forms, sizes and relationship in accordance with some
convention of representation
3.19
night condition
condition of low ambient illumination under which the adaptation level of the driver is mainly influenced by the
portion of the road ahead covered by the vehicle's own headlights and surrounding street lights, and display
and instrument brightness
NOTE Low ambient illumination is less than 50 lx.
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SIST EN ISO 15008:2009
ISO 15008:2009(E)
3.20
pixel
smallest selectively addressable element of the display surface capable of reproducing the full range of
luminance and colours
NOTE 1 “Pixel” is an abbreviation for “picture element”.
NOTE 2 Terms and definitions related to photometric quantities (e.g. illuminance, luminance, luminance contrast and
saturation) are given in CIE 17.4:1987.
3.21
quasi static information
〈reconfigurable displays〉 information that has a limited number of states, where one or other state is always
displayed and does not change frequently
EXAMPLE AM/PM, km/miles, kPa/PSI, On/Off information.
3.22
redundantly presented information
information which is presented in parallel by different means or at different positions
EXAMPLE 1 Speed can be displayed in both analogue and digital format.
EXAMPLE 2 Turn-by-turn navigation can be displayed on a central display and in parallel in the instrument cluster.
3.23
segment
pre-defined geometric form that can be used to create a character or symbol in whole or in part
EXAMPLE Stroke.
3.24
twilight condition
condition between night condition and day condition
NOTE In twilight condition, the setting of the display illumination might be in day or night setting.
4 Requirements and measurement methods
4.1 General
The following requirements shall be complied with to ensure that images on the visual displays used in on-
board TICS equipment are legible.
Conformity of the presented images to the requirements specified in this International Standard shall be tested
at a temperature within the range of 18 °C to 28 °C. The test shall not start until the illumination has reached a
stable state. The requirements are accompanied by standard measurement conditions in terms of ambient
illuminance and observer positions. Methods for measurement of contrast shall be in accordance with
SAE J1757/1:2007.
4.2 Design viewing position and illumination range
4.2.1 Design viewing position
The requirements in this subclause are applicable to displays in their installed vehicle locations, as seen from
any point in the driver eyellipses according to ISO 4513 (for passenger vehicles only).
4 © ISO 2009 – All rights reserved

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SIST EN ISO 15008:2009
ISO 15008:2009(E)
If the display is fixed to the vehicle, the relevant requirements shall be complied with from the rearmost point
of the cyclopean eyellipse. If the position of the display is adjustable, the display may be adjusted so that a
position can be found in which all the relevant requirements are complied with simultaneously. For direct
sunlight conditions, the requirements of contrast (see 4.3.2) shall only be fulfilled in the direction of the critical
specular line (CSL) (see Figure 1).
Standard default values for angles (45°/30°) as an alternative for direct sunlight measurements are acceptable
(see SAE J1757/1:2007).

a) Display at right-hand side of driver
Figure 1 (continued)
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SIST EN ISO 15008:2009
ISO 15008:2009(E)

b) Side view

c) Plan view
Key
1 display 4L left eyellipse
2 centre of the display 4R right eyellipse
3 rearmost point of the cyclopean eyellipse 5 centre of the cyclopean eyellipse
4C cyclopean eyellipse N display perpendicular direction
Figure 1 — Design viewing position
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SIST EN ISO 15008:2009
ISO 15008:2009(E)
4.2.2 Illumination range
4.2.2.1 The design illumination range establishes the four conditions of:
⎯ night,
⎯ twilight,
⎯ day with diffuse ambient light, and
⎯ day with direct sunlight.
4.2.2.2 Night condition is replicated in a dark environment such that the maximum illuminance on the
object to be measured shall not exceed 10 lx, with a relative tolerance of ± 5 %. For the measurement
procedure, see SAE J1757/1:2007, Table 1.
4.2.2.3 Twilight condition is replicated with a measurement condition specified in SAE J1757/1:2007,
4.1.2.4 and Table 1. The ambient light measured on the surface of the display (on the standard diffuse
reflector) shall be 250 lx, with a relative tolerance of ± 5 %. If the display setting is brought into the night-time
setting manually or automatically (e.g. triggered by the head lamp switch or a sun load sensor), the displayed
information shall meet the twilight requirements in 4.3.2 in the night-time setting. If the driver can manually
change the setting of the display to a higher contrast, the measurement may be made in that display setting.
4.2.2.4 Day condition with diffuse ambient light is replicated with ambient light omni-directional to the
point of measurement. The ambient light measured on the surface of the display (on the standard diffuse
reflector) shall be 5 klx, with a relative tolerance of ± 5 %. For the measurement procedure,
see SAE J1757/1:2007, 4.1 and Table 1.
4.2.2.5 Direct sunlight condition is replicated with a standard measurement condition. The illuminance
at the point of measurement shall be 45 klx, with a relative tolerance of ± 5 %. For the measurement
procedure, see SAE J1757/1:2007, 4.1 and Table 1.
4.2.2.6 For day and direct sunlight and for twilight conditions in the measurement procedure in
accordance with SAE J1757/1:2007, an artificial illumination system with light type similar to that of
CIE 85:1989, Table 4 (± 20 %) shall be used. Light sources with large spikes in the spectrum (e.g. fluorescent
lamps) should be avoided; metal halide lamps are more appropriate due to their energy in the blue part of the
spectrum. The colour temperature is secondary to this issue.
4.3 Display illumination, minimum contrast, luminance and polarity
4.3.1 Display illumination
Due to the very wide range of ambient illuminations that determine the adaptation level of the driver, the
display illumination should have a brightness control which allows adjustment over a suitable range.
4.3.2 Minimum contrast
4.3.2.1 Requirements
The minimum contrast ratio between symbol and background shall be
⎯ 5:1 for night condition,
⎯ 3:1 for twilight condition,
⎯ 3:1 for day condition, and
⎯ 2:1 for direct sunlight condition.
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SIST EN ISO 15008:2009
ISO 15008:2009(E)
This is especially important if characters are close to the minimum requirements for the dimensions (see 4.5).
Lower contrast should be excluded except for characters that are intentionally grey-shaded or desaturated in
colour to indicate some inactive status.
4.3.2.2 Character outlining
If sufficient contrast between the character and its background cannot be provided (e.g. with a dynamic
background), additional means shall be applied. This can be an outline around the character, in which case a
minimum contrast shall be provided between the body of the character/unfilled area and its outline.
The stroke width of the outline by character height ratio should be less than 0,04 for characters with serifs and
less than 0,08 for characters without serifs. If the size of a character is so small that the stroke width of the
outline would be less than 0,35 mm, an outline should be avoided to ensure readability (see Figure 2).

Key
1 body of the character/unfilled area
2 outline
3 borderline
4 background area
Figure 2 — Outlined character
Words or phrases written in outlined unfilled character (transparent body) fonts should not be used.
4.3.2.3 Changing background
If the background around the text or symbol is spatially changing in luminance or colour, minimum contrast
should be reached with the worst case background in the area adjacent to text or symbol. The contrast ratio
shall be calculated from at least two measurements in different areas of the display. If the background is
dynamic, an additional borderline should be applied around the characters to provide sufficient contrast (see
Figure 2). In this case, contrast should be measured between the outline and the borderline.
4.3.2.4 Contrast measurement
All contrast measurements shall be carried out at the centre point of the cyclopean eyellipse, as shown in
Figure 1. For bench top measurements, standard values for angles (45°/30°) may be used for direct sunlight
measurement (see SAE J1757/1:2007).
For matrix displays, the measurements shall be taken over a collection area covering at least (3 × 3) pixels
(see Figure 3). The measurement accuracy will be reduced if the measurement area is less than (3 × 3) pixels.
If the area of the character to be measured does not contain at least (3 × 3) pixels or the photometer spot size
is larger than the area of the character, find a larger area on the character that has at least (3 × 3) pixels and
that appears visually to have the same luminance. Measure this area.
8 © ISO 2009 – All rights reserved

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SIST EN ISO 15008:2009
ISO 15008:2009(E)
For segment displays, the measurement shall be taken within a single segment. The diameter of the collection
area shall be less than 80 % of the relevant dimension of the segment to be measured.
During the contrast measurement, the display luminance should be adjusted in the night-time condition to
“night maximum” and in daylight or direct sunlight condition to “maximum brightness”. In twilight condition, at
least one display illumination setting (e.g. day/night setting) shall be provided that meets the specified
requirement when the headlamps/parking lamps are in an “ON” (or activated) state.
For a common display that delivers different images to a driver and passengers, the contrast of the driver's
images shall be measured with passenger's image in fully white and in fully black. Required contrast shall be
fulfilled in the worse condition.
NOTE Any ghost image from dynamic crosstalk is not covered by this International Standard.

Key
1 collection area (photometer measurement spot)
2 pixel in bright state
3 pixel in dark state
Figure 3 — C
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