IEC TR 62977-5-2:2021

IEC TR 62977-5-2 ®
Edition 1.0 2021-03
TECHNICAL
REPORT
colour
inside
Electronic displays –
Part 5-2: Visual assessment – Colour discrimination according to viewing
direction
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IEC TR 62977-5-2 ®
Edition 1.0 2021-03
TECHNICAL
REPORT
colour
inside
Electronic displays –
Part 5-2: Visual assessment – Colour discrimination according to viewing

direction
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 31.120 ISBN 978-2-8322-9514-4

– 2 – IEC TR 62977-5-2:2021 © IEC 2021
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms, definitions and abbreviated terms . 7
3.1 Terms and definitions . 7
3.2 Abbreviated terms . 8
4 Introduction to visual assessment . 8
5 Standard measuring equipment and coordinate system . 10
5.1 Light measuring devices . 10
5.2 Viewing direction coordinate system . 10
6 Test patterns . 11
6.1 Geometrical construction . 11
6.2 Colour assignment . 12
6.3 Dots fill factor . 14
7 Visual assessment method . 15
7.1 General description of the assessment . 15
7.2 Test room conditions . 15
7.3 DUT parameters . 16
7.4 Observers . 16
7.5 Instructions for visual assessment method . 17
7.6 Repeatability . 18
7.7 Presentation and interpretation of the experimental assessment results . 18
Annex A (informative) Fill factor dependency . 26
Annex B (informative) Display white luminance dependency . 29
Annex C (informative) Pattern generator . 32
Bibliography . 34

Figure 1 – Comparison between the proposed visual assessment and the conventional
physical measurement . 9
Figure 2 – Definition of viewing directions by the spherical angles of θ and φ . 10
Figure 3 – Layout for horizontal viewing direction . 11
Figure 4 – Pattern structures. 12
Figure 5 – Colour assignment of test pattern . 14
Figure 6 – Test environment . 15
Figure 7 – Average CMF according to ethnic origin . 17
Figure 8 – Assessment procedure . 18
Figure 9 – Visual assessment results: statistical plot (upper figure) and mean
recognition rates (lower figure) . 19
Figure 10 – Statistical plot (upper) and mean of colour differences (lower) of test
patterns . 20
Figure 11 – Process of S-CIELAB transformation . 21
Figure 12 – Contrast sensitivity function of HVS. 21
Figure 13 – S-CIELAB results: statistical plot (upper) and mean colour difference
(lower) . 22

Figure 14 – Correlation between physical measures and S-CIELAB results . 23
Figure 15 – Correlation between visual assessment and S-CIELAB method . 23
Figure 16 – Pattern dependency . 24
Figure 17 – Observer dependency . 25
Figure A.1 – Fill factor variation . 26
Figure A.2 – FF dependency . 27
Figure A.3 – Colour difference relationship between pictorial image and test patterns
with various FF . 28
Figure B.1 – Colour reproduction performance of the DUT . 30
Figure B.2 – White luminance dependency . 31
Figure C.1 – Pattern generator user interface . 33

Table 1 – Measurement directions for DUTs in living rooms . 11
Table 2 – Reference colours of test pattern . 13
Table 3 – Test room condition . 15
Table 4 – Experimental setup of the DUT . 16
Table 5 – Correlation coefficients . 24
Table B.1 – Experimental setup and parameters . 29

– 4 – IEC TR 62977-5-2:2021 © IEC 2021
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ELECTRONIC DISPLAYS –
Part 5-2: Visual assessment –
Colour discrimination according to viewing direction

FOREWORD
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IEC TR 62977-5-2 has been prepared by IEC technical committee 110: Electronic displays. It
is a Technical Report.
The text of this Technical Report is based on the following documents:
Draft Report on voting
110/1227/DTR 110/1251A/RVDTR
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 Technical Report is English.
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 IE
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