SIST EN ISO 9241-392:2017

Ergonomics of human-system interaction - Part 392: Ergonomic recommendations for the reduction of visual fatigue from stereoscopic images (ISO 9241-392:2015)

ISO 9241-392:2015 establishes recommendations for reducing the potential visual discomfort and visual fatigue experienced during viewing of stereoscopic images under defined viewing conditions. Visual fatigue and discomfort might be produced by the stereoscopic optical stimulus of disparate images that were presented binocularly.
ISO 9241-392:2015 is also applicable to the final products of stereoscopic presentations which depend on stereoscopic image content and stereoscopic displays when viewed under appropriate defined conditions. Therefore, the recommendations are intended for people responsible for the design, development, and supply of stereoscopic image content as well as stereoscopic displays.
NOTE 1 See Annex B for appropriate viewing conditions.
The recommendations in this part of ISO 9241 are applicable to stereoscopic displays such as those with glasses and two-view autostereoscopic displays, stereoscopic head-mounted displays, and stereoscopic projectors. Moreover, they are applicable to stereoscopic image content intended to be presented on the above-mentioned stereoscopic displays and stereoscopic presentations that are realized by the combinations of these images and displays.
NOTE 2 Annex C presents numerical criteria as an informative reference.
NOTE 3 Other guidance might need to be established by referring to this part of ISO 9241 when requirements and recommendations specific to each type of stereoscopic image content or stereoscopic display become necessary.
NOTE 4 ITU generally sets the standards for broadcasting.
NOTE 5 ISO 9241‑303:2011, Annex E provides guidelines for virtual displays which are intended for stereoscopic head-mounted displays.

Ergonomie der Mensch-System-Interaktion - Teil 392: Ergonomische Anforderungen zur Reduktion visueller Ermüdung durch stereoskopische Bilder (ISO 9241-392:2015)

Ergonomie de l'interaction homme-système - Partie 392: Exigences ergonomiques pour diminuer la fatigue visuelle induite par des images stéréoscopiques (ISO 9241-392:2015)

L'ISO 9241-392:2015 fournit des recommandations visant à réduire la gêne et la fatigue visuelles éventuelles ressenties lors de l'observation d'images stéréoscopiques dans des conditions d'observations définies. La gêne et la fatigue visuelles peuvent être dues au stimulus optique stéréoscopique d'images disparates présentées de façon binoculaire.
L'ISO 9241-392:2015 est également applicable aux produits finaux des présentations stéréoscopiques, lesquels dépendent des contenus d'images stéréoscopiques et des écrans stéréoscopiques, lorsque ceux-ci sont observés dans des conditions définies appropriées. En conséquence, les recommandations concernent les personnes en charge de la conception, du développement et de la fourniture de contenus d'images stéréoscopiques; elles concernent également les écrans stéréoscopiques.
Les recommandations de l'ISO 9241-392:2015 sont applicables aux écrans stéréoscopiques, tels que ceux utilisant des lunettes stéréoscopiques, des écrans autostéréoscopiques deux-vues, des visiocasques et des projecteurs stéréoscopiques. En outre, elles sont applicables aux contenus d'images stéréoscopiques destinés à être présentés sur les écrans stéréoscopiques mentionnés ci-dessus, ainsi qu'aux présentations stéréoscopiques réalisées par les combinaisons de ces images et de ces affichages.

Ergonomija medsebojnega vpliva človek-sistem - 392. del: Ergonomska priporočila za zmanjšanje vizualne utrujenosti zaradi gledanja stereoskopskih slik (ISO 9241-392:2015)

ISO 9241-392:2015 vzpostavlja priporočila za zmanjšanje morebitnega vizualnega neugodja ali utrujenosti zaradi gledanja stereoskopskih slik pod določenimi pogoji gledanja. Do vizualne utrujenosti ali neugodja lahko pride zaradi stereoskopskega optičnega dražljaja pri gledanju različnih binokularno predstavljenih slik.
ISO 9241-392:2015 se uporablja tudi za končne proizvode stereoskopskih predstavitev, ki so odvisni od vsebine stereoskopske slike in stereoskopskih prikazovalnikov pri gledanju pod ustreznimi določenimi pogoji. Priporočila so zato namenjena osebam, odgovornim za oblikovanje, razvoj in posredovanje vsebine stereoskopskih slik ter stereoskopskih prikazovalnikov.
OPOMBA 1: Za ustrezne pogoje gledanja glej dodatek B.
Priporočila v tem delu standarda ISO 9241 se uporabljajo za stereoskopske prikazovalnike, kot so prikazovalniki z očali in samostereoskopski prikazovalniki z dvojnim pogledom, stereoskopski naglavni prikazovalniki in stereoskopski projektorji. Poleg tega se uporabljajo za vsebino stereoskopskih slik, namenjeno za predstavitev z zgoraj omenjenimi stereoskopskimi prikazovalniki, in stereoskopske predstavitve, upodobljene s kombinacijo teh slik in prikazovalnikov.
OPOMBA 2: Dodatek C podaja številska merila kot informativno referenco.
OPOMBA 3: V primeru potrebnih zahtev in priporočil, specifičnih za posamezno vrsto vsebine stereoskopskih slik ali stereoskopskega prikazovalnika, je treba vzpostaviti druga navodila ob sklicevanju na ta del standarda ISO 9241.
OPOMBA 4: Standarde za oddajanje običajno pripravi Mednarodna zveza za telekomunikacije.
OPOMBA 5: ISO 9241 303:2011, dodatek E podaja smernice za virtualne prikazovalnike, ki so namenjeni za uporabo kot stereoskopski naglavni prikazovalniki.

General Information

• Status: Published
• Public Enquiry End Date: 29-Sep-2016
• Publication Date: 11-Jun-2017
• ICS: 13.180 - Ergonomics
• ICS: 35.180 - IT Terminal and other peripheral equipment
• Technical Committee: VSN - Safety of machinery
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 14-Mar-2017
• Due Date: 19-May-2017
• Completion Date: 12-Jun-2017
• Ref Project: EN ISO 9241-392:2017 - Ergonomics of human-system interaction - Part 392: Ergonomic recommendations for the reduction of visual fatigue from stereoscopic images (ISO 9241-392:2015)

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN ISO 9241-392:2017
01-september-2017
(UJRQRPLMDPHGVHERMQHJDYSOLYDþORYHNVLVWHPGHO(UJRQRPVND
SULSRURþLOD]D]PDQMãDQMHYL]XDOQHXWUXMHQRVWL]DUDGLJOHGDQMDVWHUHRVNRSVNLKVOLN
,62
Ergonomics of human-system interaction - Part 392: Ergonomic recommendations for
the reduction of visual fatigue from stereoscopic images (ISO 9241-392:2015)
Ergonomie der Mensch-System-Interaktion - Teil 392: Ergonomische Anforderungen zur
Reduktion visueller Ermüdung durch stereoskopische Bilder (ISO 9241-392:2015)
Ergonomie de l'interaction homme-système - Partie 392: Exigences ergonomiques pour
diminuer la fatigue visuelle induite par des images stéréoscopiques (ISO 9241-392:2015)
Ta slovenski standard je istoveten z: EN ISO 9241-392:2017
ICS:
13.180 Ergonomija Ergonomics
35.180 Terminalska in druga IT Terminal and other
periferna oprema IT peripheral equipment
SIST EN ISO 9241-392:2017 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 9241-392:2017

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SIST EN ISO 9241-392:2017


EN ISO 9241-392
EUROPEAN STANDARD

NORME EUROPÉENNE

March 2017
EUROPÄISCHE NORM
ICS 13.180; 35.180
English Version

Ergonomics of human-system interaction - Part 392:
Ergonomic recommendations for the reduction of visual
fatigue from stereoscopic images (ISO 9241-392:2015)
Ergonomie de l'interaction homme-système - Partie Ergonomie der Mensch-System-Interaktion - Teil 392:
392: Exigences ergonomiques pour diminuer la fatigue Ergonomische Anforderungen zur Reduktion visueller
visuelle induite par des images stéréoscopiques (ISO Ermüdung durch stereoskopische Bilder (ISO 9241-
9241-392:2015) 392:2015)
This European Standard was approved by CEN on 8 February 2017.

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-CENELEC 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-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and United Kingdom.





EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2017 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 9241-392:2017 E
worldwide for CEN national Members.

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SIST EN ISO 9241-392:2017
EN ISO 9241-392:2017 (E)
Contents Page
European foreword . 3

2

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SIST EN ISO 9241-392:2017
EN ISO 9241-392:2017 (E)
European foreword
The text of ISO 9241-392:2015 has been prepared by Technical Committee ISO/TC 159 “Ergonomics” of
the International Organization for Standardization (ISO) and has been taken over as EN
ISO 9241-392:2017 by 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 September 2017, and conflicting national standards
shall be withdrawn at the latest by September 2017.
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.
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,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta,
Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.
Endorsement notice
The text of ISO 9241-392:2015 has been approved by CEN as EN ISO 9241-392:2017 without any
modification.

3

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SIST EN ISO 9241-392:2017
INTERNATIONAL ISO
STANDARD 9241-392
First edition
2015-05-15
Ergonomics of human-system
interaction —
Part 392:
Ergonomic recommendations for
the reduction of visual fatigue from
stereoscopic images
Ergonomie de l’interaction homme-système —
Partie 392: Exigences ergonomiques pour diminuer la fatigue visuelle
induite par des images stéréoscopiques
Reference number
ISO 9241-392:2015(E)
©
ISO 2015

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ISO 9241-392:2015(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO 2015, Published in Switzerland
All rights reserved. Unless otherwise specified, 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
Ch. de Blandonnet 8 • CP 401
CH-1214 Vernier, Geneva, Switzerland
Tel. [phone]
Fax [phone]
[e-mail]
www.iso.org
ii © ISO 2015 – All rights reserved

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Contents Page
Foreword .iv
Introduction .vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Guiding concepts . 3
4.1 Framework . 3
4.2 Review of factors . 4
4.2.1 General. 4
4.2.2 Interocular geometric differences . 4
4.2.3 Interocular photometric differences . 5
4.2.4 Interocular photometric interaction. 6
4.2.5 Accommodation-convergence mismatch. 6
4.2.6 Other factors to be considered for stereoscopic presentation . 7
4.2.7 Summary . 9
5 Ergonomic recommendations .10
5.1 General .10
5.2 Viewing conditions .10
5.2.1 General.10
5.2.2 Design viewing distance .10
5.2.3 Interpupillary distance .10
5.3 Interocular geometrical differences .11
5.3.1 Interocular vertical misalignment .11
5.3.2 Interocular rotational misalignment .11
5.3.3 Interocular magnification difference .11
5.4 Interocular photometric differences .11
5.4.1 Interocular luminance difference .11
5.4.2 Interocular contrast difference .12
5.4.3 Interocular chromaticity difference .12
5.5 Interocular photometric interaction .12
5.5.1 Crosstalk.12
5.6 Accommodation — convergence mismatch .12
5.7 Other factors to be considered for stereoscopic presentation .13
6 How to use the ergonomic recommendations .13
6.1 General .13
6.2 Report .13
Annex A (informative) Overview of the ISO 9241- series .14
Annex B (informative) Viewing conditions .15
Annex C (informative) Numerical values to be considered for assessment of visual fatigue
and discomfort .17
Annex D (informative) Other factors to be considered for stereoscopic presentations .27
Annex E (informative) Sample procedure for assessing applicability and conformance .29
Bibliography .31
© ISO 2015 – All rights reserved iii

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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 on the meaning of ISO specific terms and expressions related to conformity
assessment, as well as information about ISO’s adherence to the WTO principles in the Technical Barriers
to Trade (TBT), see the following URL: Foreword — Supplementary Information.
The committee responsible for this document is ISO/TC 159, Ergonomics, Subcommittee SC 4, Human-
system interaction.
ISO 9241 consists of the following parts, under the general title Ergonomic requirements for office work
with visual display terminals (VDTs):
— Part 1: General introduction
— Part 2: Guidance on task requirements
— Part 5: Workstation layout and postural requirements
— Part 6: Guidance on the work environment
— Part 11: Guidance on usability
— Part 12: Presentation of information
— Part 13: User guidance
— Part 14: Menu dialogues
— Part 15: Command dialogues
— Part 16: Direct manipulation dialogues
ISO 9241 also consists of the following parts, under the general title Ergonomics of human-system interaction:
— Part 20: Accessibility guidelines for information/communication technology (ICT) equipment and services
— Part 110: Dialogue principles
— Part 129: Guidance on software individualization
— Part 143: Forms
iv © ISO 2015 – All rights reserved

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— Part 151: Guidance on World Wide Web user interfaces
— Part 154: Interactive voice response (IVR) applications
— Part 171: Guidance on software accessibility
— Part 210: Human-centred design for interactive systems
— Part 300: Introduction to electronic visual display requirements
— Part 302: Terminology for electronic visual displays
— Part 303: Requirements for electronic visual displays
— Part 304: User performance test methods for electronic visual displays
— Part 305: Optical laboratory test methods for electronic visual displays
— Part 306: Field assessment methods for electronic visual displays
— Part 307: Analysis and compliance test methods for electronic visual displays
— Part 308: Surface-conduction electron-emitter displays (SED)
— Part 309: Organic light-emitting diode (OLED) displays
— Part 310: Visibility, aesthetics and ergonomics of pixel defects
— Part 331: Optical characteristics of autostereoscopic displays
— Part 400: Principles and requirements for physical input devices
— Part 410: Design criteria for physical input devices
— Part 420: Selection of physical input devices
— Part 910: Framework for tactile and haptic interaction
— Part 920: Guidance on tactile and haptic interactions
For the other parts under preparation, see Annex A.
© ISO 2015 – All rights reserved v

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Introduction
When a person views a three-dimensional object, the lateral distance between the eyes provides
each with a slightly different retinal image. The fusion of these retinal images by the brain provides a
single percept with an associated sense of depth termed as stereopsis. Recent advances in the imaging
technology have created a notable increase in our chances of viewing artificially-created stereoscopic
images. The technology creates two different images, one of which is seen by one eye and the other by
the other eye. Their fusion results in the sensation of stereopsis.
Stereoscopic images are appealing because of their heightened sense of reality compared with the
traditional 2D images. Presentations of stereoscopic images also provide clear depth information and, for
this reason, the broad use of stereoscopic images is anticipated in fields such as medicine and industry.
However, there are scientific data indicating that without careful consideration of the properties of the
human visual system, the stereoscopic presentation of images might induce undesirable effects.
This part of ISO 9241 describes the basic and minimal conditions for comfortable viewing of stereoscopic
images. It is intended to promote an environment in which viewers can enjoy the benefits of stereoscopic
images without adverse effects. In such an environment, new technologies for stereoscopic images can
also be actively developed and applied in various fields. This part of ISO 9241 is not intended to restrict
the freedom of expression or artistic creativity in the image culture.
This part of ISO 9241 is based on scientific findings related to the possible undesirable effects of viewing
stereoscopic images and in the future, this part of ISO 9241 can be revised as new scientific data.
This part of ISO 9241 specifies human–system interaction standards. Readers who need guidance
on other aspects of human–system interaction can therefore refer to other documents in ISO 9241
(see Annex A for an overview of the entire ISO 9241 series).
vi © ISO 2015 – All rights reserved

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SIST EN ISO 9241-392:2017
INTERNATIONAL STANDARD ISO 9241-392:2015(E)
Ergonomics of human-system interaction —
Part 392:
Ergonomic recommendations for the reduction of visual
fatigue from stereoscopic images
1 Scope
This part of ISO 9241 establishes recommendations for reducing the potential visual discomfort and
visual fatigue experienced during viewing of stereoscopic images under defined viewing conditions.
Visual fatigue and discomfort might be produced by the stereoscopic optical stimulus of disparate
images that were presented binocularly.
This part of ISO 9241 is also applicable to the final products of stereoscopic presentations which
depend on stereoscopic image content and stereoscopic displays when viewed under appropriate
defined conditions. Therefore, the recommendations are intended for people responsible for the design,
development, and supply of stereoscopic image content as well as stereoscopic displays.
NOTE 1 See Annex B for appropriate viewing conditions.
The recommendations in this part of ISO 9241 are applicable to stereoscopic displays such as those with
glasses and two-view autostereoscopic displays, stereoscopic head-mounted displays, and stereoscopic
projectors. Moreover, they are applicable to stereoscopic image content intended to be presented on
the above-mentioned stereoscopic displays and stereoscopic presentations that are realized by the
combinations of these images and displays.
NOTE 2 Annex C presents numerical criteria as an informative reference.
NOTE 3 Other guidance might need to be established by referring to this part of ISO 9241 when requirements and
recommendations specific to each type of stereoscopic image content or stereoscopic display become necessary.
NOTE 4 ITU generally sets the standards for broadcasting.
NOTE 5 ISO 9241-303:2011, Annex E provides guidelines for virtual displays which are intended for stereoscopic
head-mounted displays.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.
ISO 9241-303, Ergonomics of human-system interaction — Part 303: Requirements for electronic visual displays
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
stereopsis
binocular, visual perception of depth or three-dimensional space
Note 1 to entry: See ISO 9241-302:2008, 3.3.40.
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3.2
binocular parallax
apparent difference in the position of an object as seen separately by one eye and by the other while the
head remains in a fixed position
Note 1 to entry: See ISO/TR 9241-331:2012, 2.2.1.
Note 2 to entry: Extent of binocular parallax of a point is equivalent to the optic angle between the visual axes of
both eyes when they are fixated on the point.
3.3
horizontal disparity
difference in the relative position of visual images of an object on the two retinas
Note 1 to entry: See ISO 9241-302:2008, 3.5.26.
3.4
vergence angle
angle between the visual axes of the left and right eyes
Note 1 to entry: See ISO 9241-302:2008, 3.5.55.
3.5
accommodation
adjustment of the optics of an eye to keep an object in focus on the retina as its distance from the eye varies
Note 1 to entry: Accommodation can also be a process of adjusting the focal length of a lens.
Note 2 to entry: Accommodation can also refer to an increase in the power of a lens of an eye.
Note 3 to entry: See ISO 9241-302:2008, 3.5.1.
3.6
visual global motion
wide spatial range of visual motion composed of different velocities and directions that are systematically
aligned in a moving image
Note 1 to entry: There are generally six types of visual global motion that correspond to the different types of
motion of a camera during the shooting of images which are rotation around and translation along the pitch, yaw,
and roll axes.
3.7
stereoscopic display
display device or system that makes depth perception possible as a result of binocular parallax (3.2)
Note 1 to entry: People perceive depth owing to the retinal disparity produced by binocular parallax.
3.8
stereoscopic image content
set of image information that results in stereoscopic images (3.9) when shown on a stereoscopic display (3.7)
3.9
stereoscopic images
set of images presented on a stereoscopic display
3.10
stereoscopic presentation
presentation of stereoscopic images on a stereoscopic display
3.11
stereoscopic view
single sight produced as a consequence of fusion of left and right views of a stereoscopic presentation
(3.10) which induces stereopsis (3.1)
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3.12
interocular vertical misalignment
difference between vertical positions of the left and right views of a stereoscopic presentation
3.13
interocular rotational misalignment
difference between rotational positions of the left and right views of a stereoscopic presentation
3.14
interocular magnification difference
difference between apparent size of the left and right views of a stereoscopic presentation
3.15
interocular geometrical difference
geometrical misalignment of the left and right views of a stereoscopic presentation including interocular
vertical misalignment (3.12), interocular rotational misalignment (3.13), and interocular magnification
difference (3.14)
3.16
interocular luminance difference
difference between the luminance values of the left and right views of a stereoscopic presentation
3.17
interocular contrast difference
difference between the luminance contrast values of the left and right views of a stereoscopic presentation
3.18
interocular chromaticity difference
difference between the chromaticity values of the left and right views of a stereoscopic presentation
3.19
interocular photometric difference
photometric mismatch between the left and right views of a stereoscopic presentation including
interocular luminance difference (3.16), interocular contrast difference (3.17), and interocular chromaticity
difference (3.18)
3.20
accommodation-convergence mismatch
difference in distance information indicated by accommodation (3.5) and convergence stimuli of an object
Note 1 to entry: Accommodation-convergence mismatch can be produced when stereoscopic images are presented
on a depth plane (e.g. stereoscopic display surface) which is well nearer or further from the viewers than where
the images are simulated.
3.21
design viewing distance
distance or range of distances between the viewers’ eyes and the screen of a stereoscopic display that is
designed for stereoscopic presentation
Note 1 to entry: Design viewing distance can be specified for both stereoscopic image content (3.8), stereoscopic
displays, and stereoscopic presentation.
4 Guiding concepts
4.1 Framework
To reduce the potential visual discomfort and visual fatigue experienced during viewing of stereoscopic
images, the recommendations in this part of ISO 9241 are established based on the review of the
factors (see 4.2) that are considered in terms of the stereoscopic optical stimulus of disparate images
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presented binocularly. Therefore, other standards specific to each type of stereoscopic image content or
stereoscopic display could be established by referring to this part of ISO 9241.
4.2 Review of factors
4.2.1 General
This part of ISO 9241 focuses on the major factors that have the potential to induce visual discomfort and
visual fatigue during viewing of stereoscopic images. These factors, listed below, have been empirically
determined and are widely recognized in the scientific literature. Since these factors are affected by the
viewing conditions, such as the viewing distance, the viewing conditions should also be specified.
1) Interocular geometrical differences: Interocular vertical misalignment, interocular rotational
misalignment, and interocular magnification difference.
2) Interocular photometric differences: Interocular luminance difference, interocular contrast
difference, and interocular chromaticity difference.
3) Accommodation-convergence mismatch.
4) Other factors to be considered for stereoscopic presentation: Interocular temporal asynchrony,
visual motion-induced motion sickness, and vergence limits.
In establishing guidance, the above-mentioned factors must be considered in light of their level of
importance by reviewing the four items listed below.
a) Efficacy of factor: The probability that a factor will cause visual discomfort or visual fati
...