INTERNATIONAL STANDARD ISO 15008 Third edition 2017-02 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 de commande et d’information des transports — Spécifications et modes opératoires pour la présentation visuelle bord du véhicule Reference number ISO 15008:2017(E) © ISO 2017 ISO 15008:2017(E) COPYRIGHT PROTECTED DOCUMENT © ISO 2017, Published in Switzerland All rights reserved Unless otherwise specified, no part o f 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 o f the requester ISO copyright o ffice Ch de Blandonnet • CP 401 CH-1214 Vernier, Geneva, Switzerland Tel +41 22 749 01 11 Fax +41 22 749 09 47 copyright@iso.org www.iso.org ii © ISO 2017 – All rights reserved ISO 15008:2017(E) Contents Page Foreword iv Introduction v Scope Normative references Terms and definitions Requirements and measurement methods 4.1 General 4.2 Design viewing position and illumination range 4.2.1 Design viewing position 4.2.2 Illumination range 4.3 Display illumination, minimum contrast, luminance and polarity 4.3.1 Display illumination 4.3.2 Minimum contrast ratio 4.3.3 Display mode 10 4.4 Colour combinations 10 4.5 Alphanumerical character dimensions 11 4.5.1 General 11 4.5.2 Height 11 4.5.3 Width by height ratio: Proportion o f the type face 11 4.5.4 Stroke width by height ratio: Weight o f the type face 12 4.5.5 Spacing 12 4.5.6 Case 13 4.6 Pixel matrix character format 14 4.6.1 Upper and lower case o f alphanumeric Latin, Greek, Cyrillic characters 14 4.6.2 Automotive symbols 15 4.6.3 Non-Latin characters 16 4.7 Reflections and glare 16 4.8 Characteristics of presentation 16 4.8.1 Image instability 16 4.8.2 Image flashing 16 4.9 Redundant information displays 17 Annex A (normative) Definition and measurement o f character dimensions 18 Annex B (informative) Colour combinations 20 Annex C (informative) Terminology of typographic terms and visual dictionary 21 Bibliography 25 © ISO 2017 – All rights reserved iii ISO 15008:2017(E) Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies) The work o f 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 o f electrotechnical standardization The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part In particular the different approval criteria needed for the di fferent types o f ISO documents should be noted This document was dra fted in accordance with the editorial rules of the ISO/IEC Directives, Part (see www.iso org/directives) Attention is drawn to the possibility that some o f the elements o f this document may be the subject o f patent rights ISO shall not be held responsible for identi fying any or all such patent rights Details o f any patent rights identified during the development o f 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 in formation given for the convenience o f users and does not constitute an endorsement For an explanation on the meaning o f ISO specific terms and expressions related to formity assessment, as well as information about ISO’s adherence to the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see the following URL: www.iso.org/iso/foreword.html The committee responsible for this document is ISO/TC 22, Road vehicles, Subcommittee SC 39, Ergonomics This third edition cancels and replaces the second edition (ISO 15008:2009), which has been technically revised with the following changes: — Introduction was modified; — Scope was modified (heavy vehicles partly excluded); — test conditions for direct sunlight have been changed; — character height was modified; — character proportion was modified; — character weight criterion was modified; — intercharacter spacing was modified; — word spacing was modified; — a new subclause on text case was added; — the subclause on character outlines was modified; — a new subclause on character shadows was added; — the subclause on Non-Roman text was modified and renamed Non-Latin iv © ISO 2017 – All rights reserved ISO 15008:2017(E) Introduction Driving is a complex task requiring continuous allocation of attentional resources to both driving and non- d rivi ng tas ks B e c au s e o f th i s , d ri vi ng i s an i nterac tive b a la nce b e twe en co gn iti ve, phys ica l, s omato s en s or y, vi s ua l a nd p s ychomo tor s ki l l s D river and veh icle form an i nte grate d s ys tem th at i nclude s the envi ron ment, veh icle control s , a nd d i s plays col le c tively defi ne d as the tran s p or t i n formation and control s ys tem s ( T I C S ) Si nce d rivi ng is an i nterac tive s ys tem s s titute i mp or ta nt ac tivity, fac tors veh icle ch arac teri s tics in combi nation with huma n c ap abi l itie s i n the p er formance o f th i s T I C s ys tem In order to achieve optimal driver performance, the purpose of TICS is to support drivers in their pri mar y ta s k s uch that p er forma nce, com for t and s a fe ty are i ncre as e d and overa l l d river worklo ad i s no t ne gatively i n fluence d b y the u s e o f T IC S O ne s e t o f cha rac teri s tic s hu ma n o f vi s ua l c ap abi l itie s , the d i s plays range Sp e ci fic a l ly, o f i l lu m i nation tho s e fac tors as p e c ts cond ition s i n fluenc i ng th i s pro ce s s i nvolve s the o f d i s plays and lo c ation de s igne d o f the to accom mo date d i s play with re s p e c t to the d river T h i s i s e s p e c ia l ly i mp or tant s i nce vi s ua l s p e ci fic ation s mu s t i nclude a wide nge o f envi ron menta l cond ition s a nd s titute on ly one ne ce s s ar y cond ition for ade quate p er forma nce, comfort and workload The purpose of this document is to standardize visual presentation © ISO 2017 – All rights reserved v INTERNATIONAL STANDARD ISO 15008:2017(E) Road vehicles — Ergonomic aspects of transport in formation and control systems — Specifications and test procedures for in-vehicle visual presentation Scope This c u ment s p e c i fie s m i n i mum re qu i rements for the i mage qua l ity a nd le gibi l ity o f d i s p lays conta i n i ng dyna m ic (cha nge able) vi s ua l i n formation pre s ente d to the d river o f a p as s enger c ar b y onb o ard tra n s p or t i n formation a nd control s ys tem s ( T I C S ) u s e d wh i le the veh icle i s i n mo tion H e av y vehicles are excluded for the requirements of contrast and font size since these chapters reference ISO 451 wh ich i ndep endent is on ly appl ic able o f d i s play for te ch nolo gie s p a s s enger veh icle s Re ference to te s t T he s e me tho d s re qu i rements and are i ntende d me a s u rements for to be a s s e s s i ng compl ia nce with them have b e en i nclude d where ne ce s s a r y This c u ment i s ap p l ic ab le m a i n l y to p ercep tu a l , a nd s o me b a s ic co g n i ti ve , co mp o nents o f the vi s u a l i n fo r m atio n , i nclud i ng ch a rac ter le g ib i l i t y a nd co lo u r re co g n i tio n I t i s no t ap p l ic ab le to o ther factors affecting performance and comfort, such as coding, format and dialogue characteristics, or to d i s p l ays u s i ng: — charac ters pre s ente d a s a p ar t o f a s ymb ol or pic toria l i n formation (e g C D s ymb ol) ; — s up eri mp o s e d i n formation on the ex terna l field (e g he ad-up d i s pl ays) ; — pic toria l i mage s (e g re ar view c amera) ; — map s a nd top o graph ic repre s entation s (e g tho s e for s e tti ng navigation s ys tem s) ; or — quasi-static information (e.g AM/PM, km/miles, kPa/PSI, On/Off information) Normative references T he fol lowi ng c u ments are re ferre d to i n the tex t i n s uch a way th at s ome or a l l o f thei r content s titute s re qu i rements o f th i s c u ment For date d re ference s , on ly the e d ition cite d appl ie s For u ndate d re ference s , the late s t e d ition o f the re ference d c ument (i nclud i ng a ny amend ments) appl ie s ISO 4513, Road vehicles — Visibility — Method for establishment of eyellipses for driver’s eye location CIE 85:1989, Solar spectral irradiance SAE J1757/1:2015, Standard Metrology for Vehicular Displays CIE S 017/E:2011 ILV, International lighting vocabulary Terms and definitions For the pu rp o s e s o f th i s c ument, the term s and defi n ition s given i n C I E S 017/E : 011 I LV and the fol lowi ng apply ISO and IEC maintain terminological databases for use in standardization at the following addresses: — IEC Electropedia: available at http://www.electropedia org/ — ISO Online browsing platform: available at http://www.iso org/obp © ISO 2017 – All rights reserved ISO 15008:2017(E) 3.1 adaptation adjustment o f the eye’s sensitivity to the brightness (3.2 ) o f the observed visual field by chemical and physical processes within the eye Note to entry: Dark adaptation occurs at a slower rate than does light adaptation 3.2 brightness subjective attribute o f light sensation by which a stimulus appears to be more or less intense or to emit more or less light 3.3 chromatic having hue or being coloured, appearing di fferent in quality from a neutral grey having the same brightness (3.2) Note to entry: It is related to the colour properties o f a visual stimulus 3.4 contrast ratio RC ratio between the luminance Lhigh and the luminance Llow Note to entry: R C = L high L low Note to entry: Terms and definitions related to photometric quantities (e.g illuminance, luminance, luminance contrast and saturation) are given in CIE S 017/E:2011 ILV In CIE S 017/E:2011 ILV, it is referred as luminance contrast ratio 3.5 critical specular line CSL line from the centre o f the display to the centre o f the eyellipse (3.10) 3.6 cyclopean eyellipse elliptical volume combining the left and the right eyellipse (3.10) of the driver into one single volume located in the centre between them 3.7 day condition condition with diffuse ambient light 3.8 direct sunlight condition condition under which the viewing conditions are mainly influenced by direct light from the sun on the display sur face 3.9 dynamic information information that has more than two stages of change 3.10 eyellipse elliptical shape o f the driver eye range Note to entry: As defined in ISO 4513 Note to entry: See definition o f 95th percentile eyellipse in ISO 4513 © ISO 2017 – All rights reserved ISO 15008:2017(E) N o te to entr y: I t i s the contrac tion o f the word s “eye” a nd “el l ip s e” 3.11 flash i ntende d p erio d ic va riation o f the lu m i nance o f a l ight or vi s ua l i n formation, norma l ly given va lue, typic a l ly u s e d for from “OF F ” to a attrac ti ng attention N o te to entr y: Ter m s a nd de fi n itio n s rel ate d to p ho tome tr ic qu a ntitie s (e g i l lu m i n a nce , lu m i n a nce , lu m i n a nce contrast ratio (3.4), saturation) are given in CIE S 017/E:2011 ILV 3.12 flicker unintended perceived temporal variation of the brightness (3.2 ) o f a vi s ua l s ti mu lu s , u s ua l ly generate d b y re fres h pro ce s s o f the d i s play content or b y va ri ation o f the lu m i na nce o f the b ackl ight N o te to entr y: Ter m s a nd de fi n itio n s rel ate d to p ho tome tr ic qu a ntitie s (e g i l lu m i n a nce , lu m i n a nce , lu m i n a nce contrast ratio (3.4), saturation) are given in CIE S 017/E:2011 ILV 3.13 disability glare da z z l i ng or d i s abl i ng e ffe c t pro duce d b y a bright l ight N o te to entr y: T h i s i s a re ti n a l e ffe c t, pr i m a r i l y c au s e d b y l ight s c atter i n the e ye , wh ich pro duce s a lu m i no u s veil over the retinal image and thus reduces contrast 3.14 discomfort glare d i s trac ti ng or d i s rup ti ng e ffe c t o f bright p oi nt s ou rce s i n the field o f view N o te to entr y: T h i s i s a p ercep tu a l e ffe c t, i nter feri n g with vi s u a l attentio n a nd s ele c tion 3.15 jitter unintended periodic movement of an image or parts of it 3.16 legibility visual properties of a character or graphics representation that determine the ease with which it can be recognized N o te to entr y: S e e a l s o readability (3.21) 3.17 map repre s entation on pl ane s ur face o f the fe atu re s o f a ne c te d p ar t o f the e a r th s u r face (e s p e ci a l ly o f the ro ad a nd tra ffic envi ron ment) , s hown i n thei r repre s entative accordance with some convention of representation form s , s i z e s and relation s h ip i n 3.18 night condition condition of low ambient illumination under which the adaptation (3.1 f brightness (3.2) i n fluence d b y the p or tion o ) level o f the d river i s mai n ly the ro ad a he ad covere d b y the veh icle’s own he ad l ights and s u rrou nd i ng s tre e t l ights , a nd d i s play a nd i n s tru ment N o te to entr y: L ow a mb ient i l lu m i n ation i s le s s th a n l x 3.19 pixel s ma l le s t s ele c tively add re s s able element o f the d i s play s u r face c ap able o f repro duci ng the luminance and colours N o te to entr y: “P i xel” i s a n ab b re vi ate d term © ISO 2017 – All rights reserved for fu l l range o f “p ic tu re element” ISO 15008:2017(E) Note to entry: Terms and definitions related to photometric quantities (e.g illuminance, luminance, luminance contrast ratio (3.4), saturation) are given in CIE S 017/E:2011 ILV 3.20 quasi-static information in formation that has a limited number o f states, where one or another state is always displayed and does not change frequently EXAMPLE AM/PM, km/miles, kPa/PSI, on/off information 3.21 readability visual properties o f a series o f characters or words that determine the ease with which they can be read Note to entry: See also legibility (3.16) 3.22 redundantly presented information in formation which is presented in parallel by di fferent means or at di fferent positions EXAMPLE Speed can be displayed in both analogue and digital format EXAMPLE 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 static information in formation that does not change, especially physical units EXAMPLE km, miles, kPa, PSI, mph, kph 3.25 twilight condition condition between night condition (3.18) and day condition (3.7) Note to entry: In twilight condition, the setting o f the display illumination might be in day or night setting 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 Con formity o f the presented images to the requirements specified in this document shall be tested at an ambient 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 © ISO 2017 – All rights reserved ISO 15008:2017(E) Key width height Figure — Proportions of letter H 4.5.4 Stroke width by height ratio: Weight o f the type face Typ e face s s ele c te d s hou ld no t b e to o l ight or to o b old T he prop or tion o f the s tem width to the a s cender height (as c an b e s e en b y d ivid i ng the width o f the lower c a s e le tter L b y its height) (s e e range b e twe en 10 % and % Typ e face s th at increasing the font size fa l l Figure 8) should b e twe en % and 10 % c an b e accom mo date d b y Key width height Figure — Proportions of lower case L 4.5.5 Spacing Typ e face s s ele c te d s hou ld be even ly a nd prop or tionately s p ace d a nd the s p ace b e twe en ver tic a l s troke s (s uch as b e twe en l and m) s hou ld nge b e twe en % and % o f the s tem width T he s p ace b e twe en d iagona l ch arac ters and a ver tica l (s uch a s b e twe en v and l) s hou ld b e a m i n i mu m o f % o f the stem width Two diagonal characters should not touch (see Figure 9) T he word s s p ace i s relate d to the i ntercharac ter s p aci ng o f the typ e face T he prop or tion o f word s p ace Figure 10) Line spacing shall be maintained at a minimum of one average stem width Text line spacing, T, is f f following text line to i ntercharac ter s p ace c an range b e twe en % and 0 % (s e e defi ne d by the d i s tance b e twe en the de s cender l i ne o 12 the c u rrent te xt l i ne a nd the a s cender l i ne o the © ISO 2017 – All rights reserved ISO 15008:2017(E) Key vl space stem width lm space Figure — Inter-character spacing in relation to stem width Key lm space space Figure 10 — Word space in relation to inter-character spacing 4.5.6 Case D yna m ic tex t, e s p e ci a l ly tex t relate d to me s s age s that are u rgent i n natu re, shou ld b e s e t i n m i xe d or lower c as e, u n le s s o ther wi s e re qui re d b y the nationa l b o dy Uppercase could be used for texts that are a permanent part of the user interface (UI), such as buttons f f f required (see Figure 11) and lab el s , as the re quenc y and pre d ic tabi l ity o © ISO 2017 – All rights reserved app e ara nce o s uch te xt wi l l i mprove the re ad i ng ti me 13 ISO 15008:2017(E) Figure 11 — Lower case vs upper case 4.6 Pixel matrix character format 4.6.1 Upper and lower case o f alphanumeric Latin, Greek, Cyrillic characters A (5 × 7) pixel (width by height) character matrix shall be the minimum used for alphanumeric characters, i f characters are only upper case I f legibility o f an individual alphanumeric character is important for the task, a (7 × 9) pixel (width by height) character matrix should be the minimum I f characters with descenders are used, a (7 × 11) pixel (width by height) character matrix should be the minimum A (4 × 5) pixel (width by height) alphanumeric character matrix shall be the minimum for the following: — subscripts and superscripts; — numerators and denominators o f fractions displayed in a single-character position; — in formation unrelated to the task (e.g the copyright symbol, ©) It is not necessary for the subscript or superscript to extend below or above the main character (see Figure 12) 14 © ISO 2017 – All rights reserved ISO 15008:2017(E) Key (5 × 7) pixel matrix for alphanumeric character (4 × 5) pixel matrix for subscript (4 × 5) pixel matrix for superscript Figure 12 — Matrix for alphanumeric character, subscript and superscript 4.6.2 Automotive symbols For automotive symbols in accordance with ISO 2575, or similar, a (32 × 32) pixel matrix should be the minimum A smaller matrix, e.g (24 × 24) pixels, may be used i f the display is capable o f grey shades © ISO 2017 – All rights reserved 15 ISO 15008:2017(E) The number o f pixels shall be determined by counting them on a suitable set o f characters and symbols 4.6.3 Non-Latin characters This document basically re fers to Latin characters as well as Greek and Cyrillic letters This subclause gives guidance for some non-Latin characters Other languages will be included depending on availability o f su fficient knowledge A (16 × 16) pixel (width by height) character matrix shall be the minimum used for Chinese characters (traditional and simplified) and Japanese (Kanji) characters NOTE Examples for (16 × 16) pixel matrices can be found in JIS X 9051 I f the legibility o f an individual Chinese character or Japanese character is key to the interpretation o f the message, a (24 × 24) pixel (width by height) character matrix should be the minimum, or modification o f characters should be used NOTE Examples for (24 × 24) pixel matrices can be found in JIS X 9052 I f only a limited and predefined set o f characters is used, and these characters are clearly discriminable from one another, a smaller pixel matrix may be used 4.7 Reflections and glare Reflections and glare visible by the driver should be minimized Additional reflection-reduction and glare-reduction or contrast-enhancement techniques, i f used, shall not cause the display to deviate from the requirements of this document 4.8 Characteristics of presentation 4.8.1 Image instability The image should be free from temporal instability (flicker) and spatial instability One factor o f spatial instability is peak-to-peak variation in the geometric location o f the image within the display (jitter): this shall not exceed 0,000 × d, where d is the viewing distance between the centre o f the cyclopean eyellipse and the centre o f the display NOTE Additional factors contributing to spatial image stability, e.g display vibrations generated by the vehicle, are not considered in this document For displays with pixels having continuous luminance distributions only, jitter can be measured using a measuring microscope with a magnification o f at least 20 The movement is determined by visual alignment of the microscope cursor, or comparator reticle, with the extreme positions of the centroid, or the edge o f a character, or test object, during the observation period For any display type, a special display-measuring device may be used This device shall be used to determine, on a scan-by-scan basis, the relative location o f a character or test object I f the device used determines movement along the horizontal and vertical axes separately, the extent o f the jitter shall be defined as the square root o f the sum o f the squares o f the maximum horizontal and vertical di fferences Observations shall continue for at least s 4.8.2 Image flashing Image flashing should be used only to attract attention and in form about critical conditions requiring an immediate action In order to attract attention, a flash frequency o f Hz to Hz with a duty cycle o f 50 % to 70 % should be used 16 © ISO 2017 – All rights reserved ISO 15008:2017(E) The flashing rate should be measured using a luminance meter aimed at the flashing picture element (i.e a pixel or segment) located in the display centre The meter should be capable o f delivering the time varying luminance values with a low-pass cut-o ff frequency o f at least 10 times the highest frequency to be measured The signal should be processed with an oscilloscope or similar instrument with adequate bandpass in order to obtain the “ON” and “OFF” durations In order to measure the “ON” and “OFF” durations (points and in Figure 13), the switching times (points 3, and in Figure 13) are established at which the luminance is equal to the average luminance between the minimum and the maximum luminance values (Llow and Lhigh in Figure 13 ) The “ON” duration is the time between points and 4, and the “OFF” duration is the time between points and Key “ON” duration “OFF” duration switch-on time switch-off time next switch-on time luminance average luminance a L high maximum luminance L low minimum luminance t time L L Figure 13 — Flashing frequency measurement The equivalent frequency (in hertz) should be obtained from the duration (in seconds) For pulse width modulated backlight, the effect of the backlight variation should be considered (e.g triggering of oscilloscope) Alternatively, a continuous stable backlight should be used for these measurements 4.9 Redundant information displays I f the same in formation is presented in more than one display, at least one o f the in formation displays shall meet the requirements o f this document Other redundant in formation displays may also meet the requirements of this document © ISO 2017 – All rights reserved 17 ISO 15008:2017(E) Annex A (normative) Definition and measurement o f character dimensions A.1 Character dimensions All the character dimensions are measured in angular values as the subtended angle of the feature (e.g height or width), as seen from the specified viewing point The angular values, expressed in radians, are derived from the linear values, in Formula (A.1): αR = (A.1) x d where αR is the angular dimension, in radians; x is the linear dimension o f the character (e.g height or width), projected on a plane perpendicular to the viewing direction; d is the viewing distance from the back centroid o f the cyclopean eyellipse Both x and d shall be expressed in homogeneous units (e.g millimetres) The angular dimension, αA, expressed in arc minutes (1 arcmin = 1°/60) is derived from the dimensions, in radians, in Formula (A.2): 180 × α R α A = 60 p (A.2) For practical use, Formula (A.2) can be written as follows: αA = 438 × x d The character dimensions shall be as defined in Figure A.1 , using characters “H” and “A” I f both normal and bold fonts are available, the character dimensions are taken from the normal font A.2 Character size measurement Character height of a particular character font shall be measured as the distance between the base line and the cap line of this font, as shown in Figure A.1 The character “H” should be used to define the character height Character width of a particular character font shall be measured as the distance between appropriate parallel edges o f the character “H”, as shown in Figure A.1 For the purposes o f the dimensional, not optical, measurement, the character edge is defined as extending to the point o f 50 % luminance di fference between the character and the background The 50 % point is determined from measurement o f the character luminance profile The measurement equipment shall be capable o f reliably measuring the smallest uni form area o f the character 18 © ISO 2017 – All rights reserved ISO 15008:2017(E) T he d i men s ion s o f the cha rac ters may a l s o b e de term i ne d b y c a lc u lation b a s e d on the d i men s ion o f the cha rac ter Key font, the d i s pl ay s p e c i fic ation, a nd the anti- a l ia s i ng s p e ci fic ation ascender line capital height x-height base line descender line Figure A.1 — Character dimensions © ISO 2017 – All rights reserved 19 ISO 15008:2017(E) Annex B (informative) Colour combinations Table B.1 provide s guidance on combi nation s o f s ymb ol colou r and b ackground colou r Table B.1 — Symbol/background colour combinations Background colour White Yellow Orange Reda, Purple Gre en, C ya n Blue a, Violet White Yellow − − o + + ++ ++ Orange o − Symbol colour Red a, Purple + o − o o + ++ − − Gre en , C ya n + o − Blue a, Violet ++ + o − − o Black + ++ Preferred + Recommended o Acceptable with high saturation differences Not recommended − − − + − − Black ++ ++ + + + − + − − a P u re re d a nd b lue s ho u ld b e avo ide d i n vie w o f the fac t th at the e ye s m ay h ave tro ub le fo c u s i n g o n the s e co lo u r s b e c au s e o f e ye ch ro m atic ab er ratio n More precise information is available in Reference [17], which contains several sections on luminance and colour contrast 20 © ISO 2017 – All rights reserved ISO 15008:2017(E) Annex C (informative) Terminology of typographic terms and visual dictionary C.1 Terminology Figure C.1 x-height cap height x:H lm space vl space stem width even spacing proportional spacing l-proportion s hows a term i nolo g y example height of lower case x height of capitals such as H ratio of x-height to cap height space between two vertical strokes such as l and m space between diagonal characters such as v and l width of vertical strokes such as l s p ac i ng o f te xt that s a u ni form rhyth m s pacing o f text that varies according to letter dimens ions; oppos ite o f mono -s pacing ratio of stem width to ascender height (the width of the vertical stroke of lower c a s e L d ivide d b y its height) © ISO 2017 – All rights reserved 21 ISO 15008:2017(E) Key lm space space vl space stem width Figure C.1 — Terminology example C.2 Why the x-height and H-proportion are important Two typ e face s c an have the s ame c apita l height but var y tremendou s ly i n how big they app e ar to b e b e c au s e the ac tua l p erceive d s i z e i s u s ua l ly dep endent on how h igh the x-height i s and how wide the proportions are C.3 Visual dictionary Figure C.2 and Figure C.3 show example conventiona l prop or tion s th at c an b e 22 fou nd of p opu la r typ e face s at de fau lt s e tti ngs T he s e show i n many o ther de s ign s © ISO 2017 – All rights reserved ISO 15008:2017(E) Figure C.2 — Example of popular typefaces at default settings Figure C.3 — Example of popular typefaces at default settings © ISO 2017 – All rights reserved 23 ISO 15008:2017(E) C.4 Example of proportional vs mono-spaced typefaces at default settings Figure C.4 s hows an e xample for a mono - s p ace d typ e face where a l l le tters have the s ame width Figure C.4 — Example for a mono-spaced typeface where all letters have the same width C.5 Example of weights and proportions that are within acceptable limits Figure C.5 shows an example of weights and proportions that are within acceptable limits Figure C.5 — Example of weights and proportions that are within acceptable limits 24 © ISO 2017 – All rights reserved ISO 15008:2017(E) Bibliography [1] [2] [3] ISO 2575, Road vehicles — Symbols for controls, indicators and tell-tales ISO 3833, Road vehicles — Types — Terms and definitions ISO 13406 (all parts) 1) , Ergonomic requirements for work with visual displays based on flat panels [4] JIS X 9051, 16-dots matrix character patterns for display devices [5] [6] [7] JIS X 9052, 24-dots matrix character patterns for dot printers B off K.R., & Lincoln J.E Engineering Data Compendium: Human Perception and Performance AAMRL, Wright-Patterson AFB, OH, USA, 1988 I mbe au D., Wierwille W.W., B e auch amp Y Age, display design and driving performance [8] M ourant [9] [10] [11] [12] Peacock and Karwowski, 1993, pp 339 R.R., & L angol f G.D Luminance specifications for automobile instrument panels Hum Factors 1976, 18 pp 71–84 P e acock B., & K arwowski W Automotive Ergonomics Taylor and Francis, 1993 S mi th S.L Letter Size and Legibility Hum Factors 1979, 21 pp 661–670 Widdel H., & Post D.L eds Colour in Electronic Displays Plenum Press, New York, 1992 B hise V.D., & H ammoudeh R.W A PC Based Model for Prediction of Visibility and Legibility for a Human Factors Engineer’s Tool Box, Proceedings o f the Human Factors and Ergonomics Society 48th Annual Meeting in New Orleans, Louisiana, September 2004 [13] Green P., G oldstein S., Z eltner K., Adams S (1988) Legibility of Text on Instrument Panels: A Literature Review (Technical Report UMTRI-88-34) Ann Arbor, MI: The University o f Michigan Transportation Research Institute (NTIS No PB 90 141342/AS) [14] Whi ttle P The Psychophysics o f Contrast Brightness In: Lightness, Brightness, and Transparency, (Gilchris t A.L ed.) Lawrence Erlbaum Associates, Hillsdale, NJ, 1994, pp 35–110 [15] B oyce P.R Human Factors in Lighting Publication CRC Press Boca Raton, USA, 2014 [16] CIE S 017/E:2011 ILV: International Lighting Vocabulary Vocabulary terms are defined online at http://eilv.cie co at/ [17] C ampbell J.L., C arney C., K antowitz B.H Human Factors Design Guidelines for Advanced Traveler Information Systems (ATIS) and Commercial Vehicle Operations (CVO) FHWA–RD–98– 057 Available at: http://www.fhwa dot.gov/publications/research/sa fety/98057/ch03a cfm #colorcntst 1) Withdrawn Replaced by ISO 9241-302:2008 © ISO 2017 – All rights reserved 25 ISO 15008:2017(E) ICS 13.180; 43.040.15 Price based on 25 pages © ISO 2017 – All rights reserved