ISO/TR 9241-380:2022
(Main)Ergonomics of human-system interaction — Part 380: Survey result of HMD (Head-Mounted Displays) characteristics related to human-system interaction
Ergonomics of human-system interaction — Part 380: Survey result of HMD (Head-Mounted Displays) characteristics related to human-system interaction
This document provides information based on a study of the characteristics of head-mounted displays (HMDs) regarding the ergonomics of human–system interaction. Although this document covers the broad range of ergonomics issues that arise, it specifically provides more-detailed information about the visual aspects of the interaction, and it provides information that could form the basis for future possible standards related to HMDs. NOTE: It is preferable to take systematic approach to consider characteristics of HMD, since HMD affects a viewer not only by visual aspects, but also by some other physical aspects.
Titre manque — Partie 380: Titre manque
General Information
Standards Content (Sample)
TECHNICAL ISO/TR
REPORT 9241-380
First edition
2022-06
Ergonomics of human-system
interaction —
Part 380:
Survey result of HMD (Head-Mounted
Displays) characteristics related to
human-system interaction
Reference number
ISO/TR 9241-380:2022(E)
© ISO 2022
---------------------- Page: 1 ----------------------
ISO/TR 9241-380:2022(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2022
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii
© ISO 2022 – All rights reserved
---------------------- Page: 2 ----------------------
ISO/TR 9241-380:2022(E)
Contents Page
Foreword .v
Introduction . vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Head-mounted displays (HMDs) . 2
5 Categories of HMDs.3
5.1 General . 3
5.2 Categorized by virtual image . 5
5.2.1 VR type . 5
5.2.2 AR type . 5
5.2.3 MR type . 5
5.3 Categorized by virtual image formation . 6
5.3.1 Imaging display and optics . 6
5.3.2 Scanning type. 6
5.3.3 Light field fype . 6
5.3.4 Holographic display with waveguide type . 7
5.4 Categorized by ocularity . 8
5.4.1 Binocular . 8
5.4.2 Biocular . 9
5.4.3 Monocular . . 9
5.5 Categorized by physical configuration . 9
5.5.1 Eyeglasses type . 9
5.5.2 Placed on eyeglasses . 9
5.5.3 Frame plus optical device . 10
5.5.4 Goggles . 10
5.5.5 Smart phone with box . 10
5.5.6 Helmet mounted . 11
5.6 Categorized by system configuration . 11
5.6.1 Wireless HMD (standalone) . 11
5.6.2 Smart phone with special optics .12
5.6.3 Wired HMD .12
5.7 Categorized by physical input devices for HMD system .12
5.7.1 HMD System without external physical input devices .12
5.7.2 HMD System with external physical input devices .12
6 HMD human-system interaction characteristics .13
6.1 Optical characteristics . 13
6.1.1 General .13
6.1.2 Distance between eyes. 18
6.1.3 Distortion and aberration . 18
6.1.4 Inter-Ocular optical properties . 21
6.1.5 For AR/MR . 26
6.1.6 For AR .29
6.1.7 For AR, video see-through properties .30
6.1.8 For light field display .30
6.2 HMD system-related characteristics . 31
6.2.1 Time delay of HMD system (latency) . 31
6.2.2 Degree of freedom . 32
6.3 Other characteristics of HMD .33
6.3.1 Physical properties.33
6.3.2 Alignment .34
6.4 Physical conditions of a viewer .34
iii
© ISO 2022 – All rights reserved
---------------------- Page: 3 ----------------------
ISO/TR 9241-380:2022(E)
6.4.1 Age . .34
6.4.2 Habituation . 35
6.4.3 Preference . 35
6.4.4 Duration . 35
6.4.5 Posture of a user . 35
6.5 Presence and immersion . 35
7 Visual induced motion sickness (VIMS) .35
7.1 General . 35
7.2 SSQ . 35
7.3 VIMS related factors . 36
8 Consideration .36
Annex A (informative) Visual Fatigue and Discomfort.37
Bibliography .39
iv
© ISO 2022 – All rights reserved
---------------------- Page: 4 ----------------------
ISO/TR 9241-380:2022(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to
the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see
www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 159, Ergonomics, Subcommittee SC 4,
Ergonomics of human-system interaction.
A list of all parts in the ISO 9241 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
v
© ISO 2022 – All rights reserved
---------------------- Page: 5 ----------------------
ISO/TR 9241-380:2022(E)
Introduction
The evolution of electronic devices has led to the growing popularity of head-mounted displays (HMDs)
for direct human–machine interaction. Although ISO 9241-303 and ISO 305 addressed HMDs as ‘virtual
displays’, the information in these documents was limited to devices available at the time, and the
evolution of HMDs requires new parameters to cover the interactions between the user and the HMD
itself. To provide the latest information to suppliers, users, and anyone who interacts with HMDs, it is
important to establish which HMD characteristics need to be considered.
Unlike a conventional display, a viewer wears an HMD to see the displayed images. In most cases,
when images are shown on a conventional display, there is a certain distance between the viewer and
display. However, as stated, a viewer of an HMD wears it, usually on their head. Obviously, such viewing
conditions affect the viewer in certain ways, by not only the optical characteristics (which are the main
concerns for conventional displays) but also other physical characteristics such as weight. Therefore,
discussing the ergonomic considerations of HMDs requires a systematic approach by considering
several aspects simultaneously, which is the aim of this document.
NOTE The International Electrotechnical Commission (IEC) also works on the standardization of HMDs (the
IEC calls them 'eyewear displays'). At the time of publication, the following IEC standards are available and are
being developed:
IEC TR 63145-1-1: 2018: Eyewear display - Part 1-1: Generic introduction
IEC 63145-20-10:2019: Eyewear display - Part 20-10: Fundamental measurement methods - Optical
properties
IEC 63145-20-20:2019: Eyewear display - Part 20-20: Fundamental measurement methods - Image quality
IEC 63145-22-10:2020: Eyewear display - Part 22-10: Specific measurement methods for AR type - Optical
properties
vi
© ISO 2022 – All rights reserved
---------------------- Page: 6 ----------------------
TECHNICAL REPORT ISO/TR 9241-380:2022(E)
Ergonomics of human-system interaction —
Part 380:
Survey result of HMD (Head-Mounted Displays)
characteristics related to human-system interaction
1 Scope
This document provides information based on a study of the characteristics of head-mounted displays
(HMDs) regarding the ergonomics of human–system interaction. Although this document covers the
broad range of ergonomics issues that arise, it specifically provides more-detailed information about
the visual aspects of the interaction, and it provides information that could form the basis for future
possible standards related to HMDs.
NOTE It is preferable to take systematic approach to consider characteristics of HMD, since HMD affects a
viewer not only by visual aspects, but also by some other physical aspects.
2 Normative references
There are no normative references in this document.
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
head-mounted display
HMD
electronic device that shows information on one or more displays attached to the head of a human
3.2
virtual reality
VR
artificial environment presented by a computer
Note 1 to entry: See Figure 1.
Note 2 to entry: Including telepresence and interaction with and reaction from the virtual environment.
[SOURCE: ISO/IEC TR 18121:2015, 3.6]
3.3
mixed reality
MR
physical and digital (virtual) objects co-exist and interact in real time
Note 1 to entry: See Figure 1.
1
© ISO 2022 – All rights reserved
---------------------- Page: 7 ----------------------
ISO/TR 9241-380:2022(E)
3.4
augmented reality
AR
reality that has virtually added information
Note 1 to entry: See Figure 1.
Note 2 to entry: AR is used in ISO 9241-910 with no definition.
Note 3 to entry: AR is used in ISO/IEC TR 18120:2016 with no definition.
Note 4 to entry: AR is used in ISO 19154:2017 with no definition.
Note 5 to entry: AR is used in ISO/IEC TR 19566-1:2017 with no definition.
3.5
reality
world or the state of things as they exist
Figure 1 — VR, MR, AR, Reality
Note 1 to entry: See Figure 1.
3.6
exit pupil
vertical/horizontal dimension of the QVS (qualified viewing space)
[SOURCE: ISO 9241-302]
4 Head-mounted displays (HMDs)
An HMD is an electronic display device that provides visual information by using one or more displays
that are placed on a human head and secured by elastic straps or earpieces or integrated in a helmet
(see Figure 2). An HMD shows information by using virtual images rather than real ones (see Figure 3).
Most HMDs consist of one or more electronic displays and proper optics that treat the images on the
display or displays so that they can be seen by one or more human eyes. In some cases, there is no
physical display, only optics (see Figure 4). Because of these considerable differences from conventional
displays, numerous characteristics need to be considered regarding human–system interaction. This
document explores those characteristics and point out new ways of evaluating HMDs regarding their
users (viewers).
Figure 2 — Example of a head-mounted display
2
© ISO 2022 – All rights reserved
---------------------- Page: 8 ----------------------
ISO/TR 9241-380:2022(E)
Key
1 virtual image
2 real image on a display
3 convex lens
Figure 3 — Example of a virtual image
Key
1 laser source
2 mirror array
3 half mirror
4 real object
5 virtual image (projected image)
Figure 4 — Example of a direct scanning HMD
5 Categories of HMDs
5.1 General
There are several ways to categorize HMDs, such as by the type of images that the device shows, how
the device forms a virtual image, ocularity, and physical configuration (Figure 5)
3
© ISO 2022 – All rights reserved
---------------------- Page: 9 ----------------------
ISO/TR 9241-380:2022(E)
Figure 5 — Example of categorizing HMDs
4
© ISO 2022 – All rights reserved
---------------------- Page: 10 ----------------------
ISO/TR 9241-380:2022(E)
5.2 Categorized by virtual image
5.2.1 VR type
The VR type of HMD displays only computer-generated images (virtual images). The HMD covers the
viewer’s eyes completely, meaning that they can see nothing except the displayed images (see Figure 6).
Figure 6 — Example of a VR HMD
5.2.2 AR type
The AR type of HMD presents images of the real surrounding environment by using either transparent
optics (see-through AR type) or electro-optical devices, such as a video camera (video-see-through
type), and it shows computer-generated images (virtual images) by using certain electro-optical devices
(see Figure 7).
Figure 7 — Example of an AR type HMD
5.2.3 MR type
The MR type of HMD presents mainly computer-generated images and imposes real images (outside
scenery) by means of either video see-through or see-through optics (see Figure 8).
Figure 8 — Example of an MR type
5
© ISO 2022 – All rights reserved
---------------------- Page: 11 ----------------------
ISO/TR 9241-380:2022(E)
5.3 Categorized by virtual image formation
5.3.1 Imaging display and optics
This type of HMD shows virtual images by both showing them on displays and forming them by using
optics (see Figure 9).
Key
1 virtual image
2 displays with real image
3 convex lenses
Figure 9 — Example of an image forming type
5.3.2 Scanning type
This type of HMD does not form images by any means; rather, it uses light rays to scan the human retina
via certain optics (see Figure 4).
5.3.3 Light field fype
The light-field approach involves providing a near-eye display by using certain optics, such as those
based on micro-lenses (see Figure 10).
6
© ISO 2022 – All rights reserved
---------------------- Page: 12 ----------------------
ISO/TR 9241-380:2022(E)
Key
1 LCD
2 micro lens array
3 half mirror
4 real object
5 virtual image (projected image)
Figure 10 — Example of a light field display
5.3.4 Holographic display with waveguide type
holographic with waveguide to provide near-eye display by using certain optics, such as micro lens-
based optics (See Figure 11).
7
© ISO 2022 – All rights reserved
---------------------- Page: 13 ----------------------
ISO/TR 9241-380:2022(E)
Key
1 light guiding element
2 LCD
3 real object
4 virtual image (projected image)
Figure 11 — Example of a holographic with waveguide display
5.4 Categorized by ocularity
5.4.1 Binocular
The binocular type of HMD shows independent images on each imaging device by using stereo
separation and stereo convergence (see Figure 12).
NOTE Two separate images are seen using two separate displays and lenses.
Figure 12 — Example of a binocular display
8
© ISO 2022 – All rights reserved
---------------------- Page: 14 ----------------------
ISO/TR 9241-380:2022(E)
5.4.2 Biocular
The bi-ocular type of HMD shows the same images on each imaging device (see Figure 13).
NOTE One image is seen using one display through two separate mirrors and lenses.
Figure 13 — Example of a biocular display
5.4.3 Monocular
The monocular type of HMD shows images on one imaging device (see Figure 14).
NOTE seeing one image by using one display and one lens
Figure 14 — Example of a monocular display
5.5 Categorized by physical configuration
5.5.1 Eyeglasses type
This type of HMD is somewhat like typical eyeglasses, having optics, a frame, a bridge over the nose and
arms that rest on the ears (see Figure 15).
NOTE Eyeglasses that have a display
Figure 15 — Example of eyeglasses type of HMD
5.5.2 Placed on eyeglasses
This type of HMD is designed to be put onto eyeglasses (see Figure 16).
9
© ISO 2022 – All rights reserved
---------------------- Page: 15 ----------------------
ISO/TR 9241-380:2022(E)
NOTE Display with optics on eyeglasses.
Figure 16 — Example of type of HMD that is placed on eyeglasses
5.5.3 Frame plus optical device
This type of HMD has a frame for mounting on the viewer’s head and one or more optical devices
attached to that frame (see Figure 17).
NOTE Display and optics on an eyewear frame.
Figure 17 — Frame and optical devices type
5.5.4 Goggles
HMD looks like goggles (see Figure 18).
Figure 18 — Example of a goggle-type HMD
5.5.5 Smart phone with box
This type of HMD consists of a smartphone and a box (see Figure 19).
10
© ISO 2022 – All rights reserved
---------------------- Page: 16 ----------------------
ISO/TR 9241-380:2022(E)
Figure 19 — Smart phone with box type
5.5.6 Helmet mounted
This type of HMD is attached to a helmet and is usually called a ‘helmet-mounted display’ (see Figure 20).
Figure 20 — Example of a helmet-mounted HMD
5.6 Categorized by system configuration
5.6.1 Wireless HMD (standalone)
HMD works without having any other connected devices such as PC (see Figure 21).
NOTE HMD has only a wireless connection.
Figure 21 — example of a wireless HMD
11
© ISO 2022 – All rights reserved
---------------------- Page: 17 ----------------------
ISO/TR 9241-380:2022(E)
5.6.2 Smart phone with special optics
This type of HMD consists of a smartphone and certain special optics (see Figure 19).
5.6.3 Wired HMD
This type of HMD is connected by a wire to another device such as a PC (see Figure 22).
NOTE HMD with a wired connection.
Figure 22 — Example of a wired HMD
5.7 Categorized by physical input devices for HMD system
5.7.1 HMD System without external physical input devices
This type of HMD system has no external physical input devices, such as remote control (see Figure 23).
Figure 23 — Example of an HMD without external physical input devices
5.7.2 HMD System with external physical input devices
This type of HMD system has external physical input devices, such as one or more wands, a steering
wheel and/or gesture-based interaction devices, such as data gloves with motion tracking (see
Figure 24).
12
© ISO 2022 – All rights reserved
---------------------- Page: 18 ----------------------
ISO/TR 9241-380:2022(E)
a) HMD system with wireless wands b) HMD system with steering wheel
Figure 24 — Examples of an HMD with external physical input devices
6 HMD human-system interaction characteristics
6.1 Optical characteristics
6.1.1 General
Figure 25 shows the principles of an HMD.
13
© ISO 2022 – All rights reserved
---------------------- Page: 19 ----------------------
ISO/TR 9241-380:2022(E)
Key
1 field of view
2 display
3 optical components
4 exit pupil
5 eye relief (see 6.1.1.5)
Figure 25 — HMD using a lens to create a virtual image from a micro-display (ISO 9241-302,
Figure 11 therein)
6.1.1.1 Focus
This is defined as the point where the geometrical lines or their prolongations conforming to the
rays diverging from or converging toward another point intersect and give rise to an image after
reflection by a mirror or refraction by a lens or optical system (see Figure 27); modified from
ISO 9241-302:2008, 3.5.24, which is based on the Merriam-Webster dictionary.
Note The definition of focal distance in ISO 9241-302:2008, 3.5.24 was incorrect.
The figure for focal distance in ISO-9241-302 (see Figure 26) was not expressed properly and will be
replaced by Figure 27 in this document.
14
© ISO 2022 – All rights reserved
---------------------- Page: 20 ----------------------
ISO/TR 9241-380:2022(E)
Key
1 display
2 apparent focal points
Figure 26 — Focus distance (ISO 9241-302) ; not expressed correctly
Note Focus distance is not correctly expressed by Figure 26.
Key
1 positive lens magnifier
2 object
3 virtual image
Figure 27 — Focus
6.1.1.2 Field of view (FOV)
For a conventional display, the FOV—that is. the width to which an image from a display spread—
is defined by the visual angle subtended by the image at the eye pupil (see Figure 28). However, for
an HMD, its viewer sees an image as a virtual one, so this definition is not directly applicable. For a
detailed discussion, see Section 5.2 of IEC 63145-1-1. As stated in IEC 63145-1-1, the FOV is related to
the followi
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.