EN ISO 13406-2:2001

Ergonomic requirements for work with visual displays based on flat panels - Part 2: Ergonomic requirements for flat panel displays (ISO 13406-2:2001)

This International Standard - establishes ergonomic image quality requirements for the design and evaluation of flat panel displays (ISO/CD 13406-1); - defines terms needed to address image quality on flat panel displays; - specifies methods of determining image quality on flat panel displays; - establishes ergonomic principles for guiding these requirements. This International Standard is applicable to: - flat panel display screens when used to perform office tasks...

Ergonomische Anforderungen für Tätigkeiten an optischen Anzeigeeinheiten in Flachbauweise - Teil 2: Ergonomische Anforderungen an Flachbildschirme (ISO 13406-2:2001)

Dieser Teil von ISO 13406
¾ legt ergonomische Anforderungen an die Bildqualität für die Gestaltung und die Beurteilung von Anzeigen in Flachbauweise fest,
¾ legt Begriffe fest, die für die Beschreibung der Bildqualität von Flachbildschirmen benötigt werden,
¾ beschreibt Methoden zur Bestimmung der Bildqualität von Flachbildschirmen,
¾ legt ergonomische Prinzipien zur Ableitung dieser Anforderungen fest.
Dieser Teil von ISO 13406 ist anwendbar auf:
Flachbildschirme, wenn sie zum Verrichten von Büroaufgaben verwendet werden,
Flachbildschirme, die aus einer regelmäßigen Anordnung von Bildelementen bestehen, die in Zeilen mit gleichmäßigen Abständen ohne Zwischenräume angeordnet sind,
die Darstellung von Schriftzeichen des lateinischen, kyrillischen und griechischen Alphabetes und von arabischen Ziffern auf Flachbildschirmen.
die Darstellung von asiatischen Zeichen, und
Flachbildschirme, die groß genug sind, um mindestens 40 Zeichen lateinischen Ursprungs anzuzeigen.
Dieser Teil von ISO 13406 ist nicht anwendbar auf:
¾ Flachbildschirmtechnologie, die Optiken benutzt, um ein Bild darzustellen, das nicht von der gleichen Größe ist wie der elekto-optische Wandler (Projektionsanwendungen von Anzeigen in Flachbauweise) oder
¾ Flachbildschirmtechnologie, die auf festen Informationsgehalt oder segmentierte alphanumerische Zeichen begrenzt ist. (Siehe 2.13 IEC SC 47C (Central Office) 3:1992).
ANMERKUNG   Einige Messmethoden dieser Norm (z. B. Kontrast, Leuchtdichte) sind nicht auf reflektive Anzeigen in Flachbauweise anwendbar. Wenn die Technik sich weiterentwickelt hat, werden diesem Teil von ISO 13406 geeignete Messmethoden hinzugefügt werden.

Exigences ergonomiques pour travail sur écrans de visualisation à panneau plat - Partie 2: Exigences ergonomiques des écrans à panneau plat (ISO 13406-2:2001)

Ergonomske zahteve za delo s prikazovalnimi zasloni na osnovi ravnih ekranov - 2. del: Ergonomske zahteve za zaslone z ravnim ekranom (ISO 13406-2:2001)

General Information

• Status: Withdrawn
• Publication Date: 30-Nov-2001
• Withdrawal Date: 14-Nov-2008
• ICS: 13.180 - Ergonomics
• ICS: 35.180 - IT Terminal and other peripheral equipment
• Technical Committee: CEN/TC 122 - Ergonomics
• Drafting Committee: CEN/TC 122/WG 5 - Ergonomics of human-computer interaction
• Current Stage: 9960 - Withdrawal effective - Withdrawal
• Start Date: 15-Nov-2008
• Completion Date: 15-Nov-2008
• Ref Project: SIST EN ISO 13406-2:2002 - Ergonomic requirements for work with visual displays based on flat panels - Part 2: Ergonomic requirements for flat panel displays (ISO 13406-2:2001)

Relations

• Replaced By: EN ISO 9241-302:2008 - Ergonomics of human-system interaction - Part 302: Terminology for electronic visual displays (ISO 9241-302:2008)
• Effective Date: 22-Apr-2009
• Replaced By: EN ISO 9241-303:2008 - Ergonomics of human-system interaction - Part 303: Requirements for electronic visual displays (ISO 9241-303:2008)
• Effective Date: 22-Apr-2009
• Replaced By: EN ISO 9241-307:2008 - Ergonomics of human-system interaction - Part 307: Analysis and compliance test methods for electronic visual displays (ISO 9241-307:2008)
• Effective Date: 22-Apr-2009
• Replaced By: EN ISO 9241-305:2008 - Ergonomics of human-system interaction - Part 305: Optical laboratory test methods for electronic visual displays (ISO 9241-305:2008)
• Effective Date: 22-Apr-2009

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN ISO 13406-2:2002
01-september-2002
Ergonomske zahteve za delo s prikazovalnimi zasloni na osnovi ravnih ekranov -
2. del: Ergonomske zahteve za zaslone z ravnim ekranom (ISO 13406-2:2001)
Ergonomic requirements for work with visual displays based on flat panels - Part 2:
Ergonomic requirements for flat panel displays (ISO 13406-2:2001)
Ergonomische Anforderungen für Tätigkeiten an optischen Anzeigeeinheiten in
Flachbauweise - Teil 2: Ergonomische Anforderungen an Flachbildschirme (ISO 13406-
2:2001)
Exigences ergonomiques pour travail sur écrans de visualisation a panneau plat - Partie
2: Exigences ergonomiques des écrans a panneau plat (ISO 13406-2:2001)
Ta slovenski standard je istoveten z: EN ISO 13406-2:2001
ICS:
13.180 Ergonomija Ergonomics
35.180 Terminalska in druga IT Terminal and other
periferna oprema IT peripheral equipment
SIST EN ISO 13406-2:2002 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 13406-2:2002

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SIST EN ISO 13406-2:2002
EUROPEAN STANDARD
EN ISO 13406-2
NORME EUROPÉENNE
EUROPÄISCHE NORM
December 2001
ICS 13.180; 35.180
English version
Ergonomic requirements for work with visual displays based on
flat panels - Part 2: Ergonomic requirements for flat panel
displays (ISO 13406-2:2001)
Exigences ergonomiques pour travail sur écrans de
visualisation à panneau plat - Partie 2: Exigences
ergonomiques des écrans à panneau plat (ISO 13406-
2:2001)
This European Standard was approved by CEN on 4 February 2001.
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 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 Management Centre has the same status as the official
versions.
CEN members are the national standards bodies of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece,
Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36  B-1050 Brussels
© 2001 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 13406-2:2001 E
worldwide for CEN national Members.

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SIST EN ISO 13406-2:2002
EN ISO 13406-2:2001 (E)
Foreword
The text of the International Standard ISO 13406-2:2001 has been prepared by Technical
Committee ISO/TC 159 "Ergonomics" in collaboration with Technical Committee CEN/TC 122
"Ergonomics", the secretariat of which is held by DIN.
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 June 2002, and conflicting national
standards shall be withdrawn at the latest by June 2002.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of
the following countries are bound to implement this European Standard: Austria, Belgium,
Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy,
Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United
Kingdom.
Endorsement notice
The text of the International Standard ISO 13406-2:2001 was approved by CEN as a
European Standard without any modification.
NOTE: Normative references to International Standards are listed in annex ZA (normative).
2

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SIST EN ISO 13406-2:2002
EN ISO 13406-2:2001 (E)
Annex ZA (normative)
Normative references to international publications
with their relevant European publications
This European Standard incorporates by dated or undated reference, provisions from other
publications. These normative references are cited at the appropriate places in the text and the
publications are listed hereafter. For dated references, subsequent amendments to or revisions
of any of these publications apply to this European Standard only when incorporated in it by
amendment or revision. For undated references the latest edition of the publication referred to
applies (including amendments).
NOTE Where an International Publication has been modified by common modifications,
indicated by (mod.), the relevant EN/HD applies.
Publication Year Title EN Year
ISO 9241-3 1992 Ergonomic requirements for office EN 29241-3 1993
work with visual display terminals
(VDTs) - Part 3: Visual display
requirements
ISO 9241-6 1999 Ergonomic requirements for office EN ISO 9241-6 1999
work with visual display terminals
(VDTs) - Part 6: Guidance on the
work environment
ISO 9241-7 1998 Ergonomic requirements for office EN ISO 9241-7 1998
work with visual display terminals
(VDTs) - Part 7: Requirements for
display with reflections
ISO 9241-8 1997 Ergonomic requirements for office EN ISO 9241-8 1997
work with visual display terminals
(VDTs) - Part 8: Requirements for
displayed colours
3

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SIST EN ISO 13406-2:2002

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SIST EN ISO 13406-2:2002

INTERNATIONAL ISO
STANDARD 13406-2
First edition
2001-12-01
Ergonomic requirements for work with
visual displays based on flat panels —
Part 2:
Ergonomic requirements for flat panel
displays
Exigences ergonomiques pour travail sur écrans de visualisation
à panneau plat —
Partie 2: Exigences ergonomiques des écrans à panneau plat





Reference number
ISO 13406-2:2001(E)
©
ISO 2001

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SIST EN ISO 13406-2:2002
ISO 13406-2:2001(E)
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ii © ISO 2001 – All rights reserved

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SIST EN ISO 13406-2:2002
ISO 13406-2:2001(E)
Contents Page
Foreword.v
Introduction.vi
1 Scope.1
2 Normative references.2
3 Definitions.2
3.1 Photometry.2
3.2 Colorimetry.4
3.3 Geometry.7
3.4 Display technology.10
3.5 Alphanumeric symbols.15
4 Symbols.17
5 Guiding principles.22
6 Performance requirements.23
7 Design requirements and recommendations .23
7.1 Design viewing distance.23
7.2 Design viewing direction .24
7.3 Design screen illuminance .28
7.4 Gaze and head-tilt angles .28
7.5 Chromaticity uniformity difference (See Figure 15).28
7.6 Character height.29
7.7 Stroke width.30
7.8 Character width-to-height ratio .30
7.9 Fill factor.30
7.10 Character format.31
7.11 Between-character spacing.31
7.12 Between-word spacing.31
7.13 Between-line spacing.31
7.14 Display luminance.32
7.15 Contrast (See Figure 19).33
7.16 Luminance balance.34
7.17 Reflections (See Figure 21) .34
7.18 Image polarity.37
7.19 Luminance uniformity (See Figure 24 and Table 14).37
7.20 Pixel faults.38
7.21 Image formation time .38
7.22 Absolute luminance coding.39
7.23 Blink coding.39
7.24 Temporal instability (flicker).39
7.25 Default colour set.39
7.26 Multicolour object size.39
7.27 Colour differences.40
7.28 Spectrally extreme colours.40
7.29 Number of colours.41
8 Measurements.41
8.1 Introduction.41
8.2 Supplier requirements.42
8.3 Test laboratory requirements.45
8.4 Test geometry.56
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SIST EN ISO 13406-2:2002
ISO 13406-2:2001(E)
8.5 Combined measurement for character design analysis.65
8.6 Combined measurement for luminance, contrast and diffuse illumination .66
8.7 Requirement evaluations.69
9 Compliance.109
Annex A (informative) Colour difference calculation .111
Annex B (informative) Flicker determination.114
Annex C (informative) Bidirectional Reflectance Distribution Function (BRDF).123
Bibliography .140


iv © ISO 2001 – All rights reserved

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SIST EN ISO 13406-2:2002
ISO 13406-2:2001(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 3.
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 part of ISO 13406 may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights.
International Standard ISO 13406-2 was prepared by Technical Committee ISO/TC 159, Ergonomics,
Subcommittee SC 4, Ergonomics of human-system interaction.
ISO 13406 consists of the following parts, under the general title Ergonomic requirements for work with visual
displays based on flat panels:
— Part 1: Introduction
— Part 2: Ergonomic requirements for flat panel displays
Annexes A, B and C of this part of ISO 13406 are for information only.
© ISO 2001 – All rights reserved v

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SIST EN ISO 13406-2:2002
ISO 13406-2:2001(E)
Introduction
ISO 13406 extends its companion standard ISO 9241 to account for the significant differences in ergonomic trade
offs present when flat panels are used.
The rationale for this part of ISO 13406 is presented in ISO 13406-1.
This part of ISO 13406 presents the requirements for visual display units (VDUs) based on flat panels as defined in
ISO 13406-1. It is intended for evaluators and users of this technology. Some document users will find part of the
material complex. Notes, figures and examples are provided to lessen the problem. The legibility of flat panels is a
principal concern. The requirements are primarily based on the visual ergonomic research used in ISO 9241-3 and
on new research referenced in this part of ISO 13406. Here, as in ISO 9241-3, some requirements are based on
visual comfort, muscular comfort and user acceptability. This part of ISO 13406 includes requirements and
recommendations that are based on legibility, comfort and acceptability that arise when multicolour displays are
used, based on the visual ergonomic research described in ISO 9241-8, but modified and extended to consider the
unique trade offs of flat panels. Legibility in the presence of ambient room light and the acceptability of unwanted
reflected images are addressed covering the flat panel aspects covered in ISO 9241-7 for cathode ray tube (CRT)
technology.
Clause 3 Definitions presents or recalls those terms needed to specify requirements and measurements. Where
possible, definitions taken from other publications are quoted verbatim. If some change has been made, the
definition is followed by a note stating “Adopted from ISO xxxx:date,x.x”. Since this part of ISO 13406 often relies
on mathematical models and physical measurements to ensure the fitness of purpose of flat panel VDUs, a
clause 8 (Symbols) is presented as a convenient reference.
Guiding principles and performance requirements’ clauses modelled on ISO 9241-3 are presented to remind
document users of the foundations of the work.
Design requirements and recommendations present the physical attributes that are to be strictly followed to
conform (indicated by the word: shall) or preferred but not necessarily required (indicated by the word: should). The
topics of design viewing distance, design viewing direction and design screen illumination depart somewhat from
the precedents of ISO 9241-3. Two reasons exist:
a) an important type of flat panel has viewing characteristics that require more careful control and consideration
of viewing direction than considered in ISO 9241-3;
b) there is no basis to assume that a flat panel VDU is tabletop mounted. These topics are presented as
ergonomically constrained, supplier-specifications. This is not unprecedented, viewing distance was handled
this way in ISO 9241-3. Once specified, these requirements become the conditions under which all other
attributes are to be measured or decided.
A departure from ISO 9241-3 is the use of area-luminance. For CRT technology, the addressed locations are
generally close together so that a high-low-high-low-high-low-pixel pattern will exhibit less contrast than a sparse
pattern. Since the flat-panel pixel area is less than 100 % optically modulated (the fill factor is less than 1), the
difference between sparse and dense pattern contrast is minor. The luminance determination has to be
complicated by the need for viewing direction precision. The use of area-luminance simplification offsets that
somewhat.
Some requirements are presented in categories. For example, some flat panels exhibit long image-formation times.
For static images, such panels are ergonomically acceptable without reservation. Not all modern applications rely
solely on such static images. Requirement categories are therefore established. If the supplied equipment has such
a limitation, the supplier/evaluator is required to identify it. The system integrator, purchaser or user then can
consider whether the category is consistent with intended applications.
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SIST EN ISO 13406-2:2002
ISO 13406-2:2001(E)
Clause 8 covering measurements is intended for evaluators of flat panel VDUs. The panel surface is sampled for
evaluation. Three evaluation sites are chosen and measured, and compliance decisions can be made from these
measurements. Panels with large requirement margins do not require precision-evaluation equipment but panels
with small margins can.
Clause 9 covering compliance is closely modelled on ISO 9241-3. The alternative test (Visual performance and
comfort test) prepared as a normative annex in an amendment to ISO 9241-3, is cited as an alternative compliance
route.
Annex A provides additional information on colour difference. Annex B extends the analytic flicker determination
method of ISO 9241-3 to luminance-time modulation that is not CRT-like. Annex C informs the users of this
International Standard of new work on an alternate modelling method for screens with reflection properties that
cannot be adequately modelled with a simple combination of luminance coefficient (diffuse reflection) and
luminance factor (specular or regular reflection) and standardized assumptions about the environment. This
method develops the bidirectional reflection distribution function. When this work progresses further, it can possibly
become a normative method and replace the method in clause 8. The bibliography cites references.
© ISO 2001 – All rights reserved vii

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SIST EN ISO 13406-2:2002

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SIST EN ISO 13406-2:2002
INTERNATIONAL STANDARD ISO 13406-2:2001(E)

Ergonomic requirements for work with visual displays based
on flat panels —
Part 2:
Ergonomic requirements for flat panel displays
1 Scope
This part of ISO 13406
 establishes ergonomic image-quality requirements for the design and evaluation of flat panel displays,
 defines terms needed to address image quality on flat panel displays,
 specifies methods of determining image quality on flat panel displays, and
 establishes ergonomic principles for guiding these requirements.
This part of ISO 13406 is applicable to
 flat panel display screens when used to perform office tasks,
 flat panel display screens that consist of a regular array of picture elements arranged in evenly spaced rows
without built-in gaps,
 the presentation of fonts based on Latin-, Cyrillic- and Greek-origin alphabetic characters and Arabic numerals
on flat panel display screens,
 the presentation of Asian characters, and
 flat panel display screens that are large enough to display at least 40 Latin-origin characters.
This part of ISO 13406 is not applicable to
 flat panel technology applied to a display that uses optics to form an image that is not the same size as the
electro-optical transducer (projection applications of flat panel displays), or
 flat panel technology applied to a display limited to fixed-messages or segmented alphanumerics.
[See 2.13 IEC SC 47C (Central Office) 3:1992].
NOTE Some of the measurement methods (e.g. contrast and luminance) in this part of ISO 13406 are not applicable for
reflective flat panels. When technology has developed, appropriate measurement methods will be added to this part of
ISO 13406.
© ISO 2001 – All rights reserved 1

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SIST EN ISO 13406-2:2002
ISO 13406-2:2001(E)
2 Normative references
The following normative documents contain provisions which, through reference in this text, constitute provisions of
this part of ISO 13406. For dated references, subsequent amendments to, or revisions of, any of these publications
do not apply. However, parties to agreements based on this part of ISO 13406 are encouraged to investigate the
possibility of applying the most recent editions of the normative documents indicated below. For undated
references, the latest edition of the normative document referred to applies. Members of ISO and IEC maintain
registers of currently valid International Standards.
CIE Publication No. 15.2:1986, Colorimetry. (Central Bureau of the Commission International d'Éclairage CIE),
Vienna, Austria.
ISO 9241-3:1992, Ergonomic requirements for office work with visual display terminals (VDTs) — Part 3: Visual
display requirements.
ISO 9241-6, Ergonomic requirements for office work with visual display terminals (VDTs) — Part 6: Guidance on
the work environment.
ISO 9241-7, Ergonomic requirements for office work with visual display terminals (VDTs) — Part 7: Requirements
for display with reflections.
ISO 9241-8:1997, Ergonomic requirements for office work with visual display terminals (VDTs) — Part 8:
Requirements for displayed colours.
3 Definitions
For the purposes of this part of ISO 13406, the following definitions apply.
NOTE The symbols used in certain definitions are explained in clause 4.
3.1 Photometry
3.1.1
area-luminance
luminance of an area of the screen that has a diameter of at least 10 pixels, such that the state of an individual
pixel has less than 2 % effect
2
NOTE Area-luminance is expressed in candelas per square metre (cd/m ).
3.1.2
background luminance
luminance of an area of the screen with no graphic images present
2
NOTE Background luminance is expressed in candelas per square metre (cd/m ).
3.1.3
contrast
〈in a perceptual sense〉 assessment of the difference in appearance of two or more parts of a field seen
simultaneously or successively (hence: brightness contrast, lightness contrast, colour contrast, etc.)
NOTE Adapted from IEC 60050 (845-02-47):1987.
3.1.4
EUT
Equipment Under Test
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SIST EN ISO 13406-2:2002
ISO 13406-2:2001(E)
3.1.5
Lambert's (cosine) law
for a surface element whose radiance or luminance is the same in all directions of the hemisphere above the
surface:
I(θ ) = I cos(θ ) (1)
n
Where I(θ ) and I are the radiant or luminous intensities of the surface element in a direction at an angle θ from the
n
normal to the surface and in the direction of that normal, respectively
[IEC 60050 (845-04-56):1987]
3.1.6
Lambertian surface
ideal surface for which the radiation coming from that surface is distributed angularly according to Lambert's cosine
law
[IEC 60050 (845-04-57):1987]
For an ideal diffuse reflectance standard:
r =p◊ q (2)
STD
STD
3.1.7
luminance contrast
ratio between the higher, L and lower, L , luminances that define the feature to be detected, measured by contrast
H L
modulation (C ) defined as:
m
L - L
HL
= (3)
C
m
L + L
HL
or contrast ratio (CR), defined as:
L
H
CR = (4)
L
L
NOTE 1 For flat panels, area-luminance targets can be used to approximate the luminances that define the feature to be
detected because pixels are discrete.
NOTE 2 Adapted from ISO 9241-3:1992, 2.22.
3.1.8
luminance coefficient (at a surface element, in a given direction, under specified conditions of illumination)
q , q
ν
quotient of the luminance
...