IEC 62715-5-1:2017

Flexible display devices - Part 5-1: Measuring methods of optical performance

IEC 62715-5-1:2017(E) specifies the standard measuring conditions and measuring methods for determining the optical performance of flexible displays in the dark or under ambient illumination. This document mainly applies to display modules that are bendable about one axis. The display is measured in a static mechanical state. The measuring methods apply to monochrome or colour displays with a single radius of curvature of 35 mm or greater.

General Information

• Status: Published
• Publication Date: 18-May-2017
• ICS: 01 - GENERALITIES. TERMINOLOGY. STANDARDIZATION. DOCUMENTATION
• ICS: 31.120 - Electronic display devices
• Technical Committee: TC 110 - Electronic displays
• Drafting Committee: WG 8 - TC 110/WG 8
• Current Stage: PPUB - Publication issued
• Start Date: 16-Jun-2017
• Completion Date: 19-May-2017

Standards Content (Sample)

IEC 62715-5-1 ®
Edition 1.0 2017-05
INTERNATIONAL
STANDARD
colour
inside
Flexible display devices –
Part 5-1: Measuring methods of optical performance
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IEC 62715-5-1 ®
Edition 1.0 2017-05
INTERNATIONAL
STANDARD
colour
inside
Flexible display devices –
Part 5-1: Measuring methods of optical performance

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 31.120 ISBN 978-2-8322-4354-1

– 2 – IEC 62715-5-1:2017  IEC 2017
CONTENTS
FOREWORD . 5
INTRODUCTION . 7
1 Scope . 8
2 Normative references . 8
3 Terms, definitions and abbreviated terms . 8
3.1 Terms and definitions . 8
3.2 Abbreviated terms . 9
4 Structure of measuring equipment . 9
4.1 Measuring configuration – Display mounting . 9
4.1.1 General . 9
4.1.2 Display mounting for uniformity measurements . 10
4.1.3 Display mounting for viewing direction measurements . 10
4.2 Light measuring device . 11
4.3 Light source configurations . 13
4.3.1 General . 13
4.3.2 Uniform hemispherical diffuse illumination . 13
4.3.3 Directed source illumination . 14
5 Standard measuring conditions . 15
5.1 Standard measuring environmental conditions . 15
5.2 Standard lighting conditions . 15
5.2.1 Dark room conditions . 15
5.2.2 Standard ambient illumination spectra . 15
5.2.3 Standard illumination geometries . 17
5.2.4 Diffuse reflectance standard . 17
5.3 Standard setup conditions . 17
5.3.1 Adjustment of display modules . 17
5.3.2 Starting conditions of measurements . 17
5.3.3 Conditions of measuring equipment . 18
5.4 Standard locations of measurement field. 18
6 Optical measuring methods in dark room conditions . 18
6.1 Luminance and its uniformity. 18
6.1.1 General . 18
6.1.2 Measuring equipment . 19
6.1.3 Screen centre luminance measuring method . 19
6.1.4 Luminance uniformity measuring method . 19
6.1.5 Luminance uniformity definition and evaluation . 20
6.2 Contrast ratio . 20
6.2.1 General . 20
6.2.2 Measuring equipment . 20
6.2.3 Measuring method . 20
6.2.4 Definition and evaluation . 20
6.3 Chromaticity, colour uniformity, and colour gamut area . 21
6.3.1 General . 21
6.3.2 Measuring equipment . 21
6.3.3 Screen centre chromaticity measuring method . 21
6.3.4 Screen centre colour gamut and colour gamut area measuring method . 22

6.3.5 Colour uniformity measuring method . 24
6.4 Peak white field correlated colour temperature . 25
6.4.1 General . 25
6.4.2 Measuring equipment . 25
6.4.3 Measuring method . 25
6.5 Viewing direction dependence . 25
6.5.1 General . 25
6.5.2 Measuring equipment . 25
6.5.3 Measuring method . 26
6.5.4 Definition and evaluation . 27
6.6 Cross-talk with display in bent state . 28
6.6.1 General . 28
6.6.2 Measuring equipment . 28
6.6.3 Measuring method . 29
7 Optical measuring method under ambient illumination . 31
7.1 Reflection measurements . 31
7.1.1 General . 31
7.1.2 Measuring conditions . 32
7.2 Ambient contrast ratio . 35
7.2.1 General . 35
7.2.2 Measuring conditions . 36
7.2.3 Measuring method . 36
7.3 Ambient display colour . 36
7.3.1 General . 36
7.3.2 Measuring conditions . 37
7.3.3 Measuring method . 37
7.4 Ambient colour gamut volume . 38
7.4.1 General . 38
7.4.2 Measuring conditions . 38
7.4.3 Measuring method . 38
7.4.4 Reporting . 40
Annex A (informative) Calculation method of ambient colour gamut volume . 42
A.1 Purpose . 42
A.2 Procedure for calculating the colour gamut volume . 42
A.3 Surface subdivision method for CIELAB gamut volume calculation . 44
A.3.1 Purpose . 44
A.3.2 Assumptions . 44
A.3.3 Algorithm . 44
A.3.4 Software example execution . 45
Bibliography . 49

Figure 1 – Example of the coordinate system used for a convex display of a constant
radius of curvature about the y-axis . 10
Figure 2 – Top view example of how a convex display can be rotated within the
measurement field . 10
Figure 3 – Top view example of display mount that rotates in the x-z plane for viewing
direction measurements . 11
Figure 4 – Optical characteristics of a spot photometer, colorimeter, or
spectroradiometer . 12

– 4 – IEC 62715-5-1:2017  IEC 2017
Figure 5 – Example of the relationship between measurement field diameter and
inclinations angles . 13
Figure 6 –
...