IEC 63145-21-20:2022

IEC 63145-21-20 ®
Edition 1.0 2022-07
INTERNATIONAL
STANDARD
colour
inside
Eyewear display –
Part 21-20: Specific measurement methods for VR image quality – Screen door
effect
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IEC 63145-21-20 ®
Edition 1.0 2022-07
INTERNATIONAL
STANDARD
colour
inside
Eyewear display –
Part 21-20: Specific measurement methods for VR image quality – Screen door

effect
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 17.180.99; 31.120 ISBN 978-2-8322-4253-7

– 2 – IEC 63145-21-20:2022 © IEC 2022
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms, definitions and abbreviated terms . 5
3.1 Terms and definitions . 5
3.2 Abbreviated terms . 6
4 Standard measurement conditions . 6
5 Measurement systems . 6
5.1 Standard coordinate system . 6
5.2 Measurement equipment . 6
5.2.1 2D imaging LMD . 6
5.2.2 Stage conditions . 6
5.2.3 Setup conditions . 6
5.3 Test patterns. 7
5.3.1 General . 7
5.3.2 Checkerboard pattern . 7
5.3.3 4 % colour window signal patterns . 7
5.4 Measuring points . 8
6 Measurement methods for screen door effect . 9
6.1 General . 9
6.2 Preparations . 9
6.3 Measurement procedures . 10
6.4 Calculation . 10
6.5 Report. 12
Annex A (informative) Moving window average (MWA) . 14
Annex B (informative) Contrast modulation and visibility . 18
Annex C (informative) Examples of non rectangular pixel layout . 19
Bibliography . 20

Figure 1 – Example of 5 × 5 checkerboard pattern . 7
Figure 2 – Example of 4 % white window signal pattern . 7
Figure 3 – Example of measuring points for the centre and multi-point measurements . 8
Figure 4 – Example of measuring points in azimuth and elevation angles . 9
Figure A.1 – Example of pseudo code of MWA. 15
Figure A.2 – Example of MWA conversion of 2D luminance data (image) . 16
Figure A.3 – Example of the horizontal cross section . 17
Figure B.1 – Example of MWA image and contrast modulation . 18
Figure B.2 – Visibility under various spatial frequency and contrast . 18
Figure C.1 – Example of non rectangular pixel layout . 19

Table 1 – Example of report table . 13

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
EYEWEAR DISPLAY –
Part 21-20: Specific measurement methods
for VR image quality – Screen door effect

FOREWORD
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IEC 63145-21-20 has been prepared by IEC technical committee 110: Electronic displays. It is
an International Standard.
The text of this International Standard is based on the following documents:
Draft Report on voting
110/1433/FDIS 110/1444/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.

– 4 – IEC 63145-21-20:2022 © IEC 2022
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/publications.
A list of all parts in the IEC 63145 series, published under the general title Eyewear display,
can be found on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
IMPORTANT – The "colour inside" logo on the cover page of this document indicates that it
contains colours which are considered to be useful for the correct understanding of its
contents. Users should therefore print this document using a colour printer.

EYEWEAR DISPLAY –
Part 21-20: Specific measurement methods
for VR image quality – Screen door effect

1 Scope
This part of IEC 63145 specifies the standard measurement conditions and measurement
methods for determining the screen door effect (SDE), which is one of the image quality aspects
of eyewear displays of virtual reality (VR) type.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies.
For undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 63145-1-2, Eyewear display – Part 1-2: Generic – Terminology
IEC 63145-20-10:2019, Eyewear display – Part 20-10: Fundamental measurement methods –
Optical properties
IEC 63145-20-20, Eyewear display – Part 20-20: Fundamental measurement methods – Image
quality
3 Terms, definitions and abbreviated terms
3.1 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 63145-1-2 and the
following apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at https://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1.1
screen door effect
SDE
visibility of inter-pixel areas due to a spatial display resolution lower than that of the human
visual system or to an insufficient pixel fill-factor/aperture ratio

– 6 – IEC 63145-21-20:2022 © IEC 2022
3.2 Abbreviated terms
2D two dimensional
CCD charge
...