IEC 63145-20-20:2019

IEC 63145-20-20 ®
Edition 1.0 2019-09
INTERNATIONAL
STANDARD
Eyewear display –
Part 20-20: Fundamental measurement methods – Image quality
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IEC 63145-20-20 ®
Edition 1.0 2019-09
INTERNATIONAL
STANDARD
Eyewear display –
Part 20-20: Fundamental measurement methods – Image quality

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 17.180.99; 31.120 ISBN 978-2-8322-7352-4

– 2 – IEC 63145-20-20:2019 © IEC 2019
CONTENTS
FOREWORD . 4
1 Scope . 6
2 Normative references . 6
3 Terms, definitions, abbreviated terms and letter symbols . 6
3.1 Terms and definitions . 6
3.2 Abbreviated terms . 7
3.3 Letter symbols (quantity symbols/unit symbols) . 7
4 Standard measurement conditions . 7
4.1 Standard environmental conditions . 7
4.2 Power supply . 7
4.3 Warm-up time . 8
4.4 Dark room conditions . 8
5 Measurement systems . 8
5.1 Standard coordinate system . 8
5.2 Measurement equipment . 9
5.2.1 Light measuring device (LMD) . 9
5.2.2 Stage conditions . 11
5.2.3 Setup conditions . 11
5.3 Test patterns. 13
5.3.1 General . 13
5.3.2 Checkerboard pattern . 13
5.3.3 Solid colour patterns . 13
5.3.4 Test patterns for Michelson contrast . 13
5.4 Measurement points . 14
6 Measurement methods for image quality . 15
6.1 General . 15
6.2 Preparation . 15
6.3 Distortion . 15
6.3.1 General . 15
6.3.2 Procedure . 16
6.3.3 Calculation . 17
6.3.4 Report . 18
6.4 Colour registration error . 18
6.4.1 General . 18
6.4.2 Procedure . 18
6.4.3 Calculation . 19
6.4.4 Report . 19
6.5 Michelson contrast . 19
6.5.1 General . 19
6.5.2 Procedure . 19
6.5.3 Calculation . 20
6.5.4 Report . 20
6.6 Focal distance (dioptre) . 20
6.6.1 General . 20
6.6.2 Procedure . 21
6.6.3 Calculation . 22

6.6.4 Report . 22
6.7 FOV based on Michelson contrast . 22
6.7.1 General . 22
6.7.2 Procedure . 22
6.7.3 Calculation . 23
6.7.4 Report . 23
6.8 Eye-box based on Michelson contrast . 23
6.8.1 General . 23
6.8.2 Procedure . 23
6.8.3 Calculation . 24
6.8.4 Report . 25
Bibliography . 26

Figure 1 – Spherical coordinate system . 9
Figure 2 – Three-dimensional Cartesian coordinate system . 9
Figure 3 – Example of LMD structure . 10
Figure 4 – Examples of measurement setup. 12
Figure 5 – Example of 5 x 5 checkerboard pattern . 13
Figure 6 – Example of Michelson contrast test pattern . 14
Figure 7 – Measuring points for the centre- and multi-point measurement . 14

Table 1 – Letter symbols (symbols for quantities, and units) . 7

– 4 – IEC 63145-20-20:2019 © IEC 2019
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
EYEWEAR DISPLAY –
Part 20-20: Fundamental measurement methods –
Image quality
FOREWORD
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