IEC 62595-2-5:2021

Display lighting unit - Part 2-5: Measurement method for optical quantities of non-planar light sources

IEC 62595-2-5:2021 specifies the measurement methods for measuring the optical characteristics of convex and concave cylindrical light sources. These non-planar light sources (NPLSs) can have either a continuous, distinct, segmented or block-wised light radiating surface, for example OLED panels, integrated LEDs, integrated mini-LEDs, micro-LEDs, laser diodes, each being either monochromatic or polychromatic.

General Information

• Status: Published
• Publication Date: 20-May-2021
• ICS: 31.120 - Electronic display devices
• ICS: 31.260 - Optoelectronics. Laser equipment
• Technical Committee: TC 110 - Electronic displays
• Drafting Committee: WG 19 - TC 110/WG 19
• Current Stage: PPUB - Publication issued
• Start Date: 04-Jun-2021
• Completion Date: 21-May-2021

Standards Content (Sample)

IEC 62595-2-5 ®
Edition 1.0 2021-05
INTERNATIONAL
STANDARD
colour
inside
Display lighting unit –
Part 2-5: Measurement method for optical quantities of non-planar light sources
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IEC 62595-2-5 ®
Edition 1.0 2021-05
INTERNATIONAL
STANDARD
colour
inside
Display lighting unit –
Part 2-5: Measurement method for optical quantities of non-planar light sources

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 31.120; 31.260 ISBN 978-2-8322-9771-1

– 2 – IEC 62595-2-5:2021 © IEC 2021
CONTENTS
FOREWORD . 5
INTRODUCTION . 7
1 Scope . 8
2 Normative references . 8
3 Terms, definitions, abbreviated terms and letter symbols . 9
3.1 Terms and definitions. 9
3.2 Abbreviated terms . 9
3.3 Letter symbols (quantity symbols/unit symbols). 10
4 Measurement devices . 11
4.1 General . 11
4.2 Spot-type light measuring device . 11
4.3 Spectroradiometer (spectral radiance-meter) . 12
4.4 Electrical measurement devices . 12
4.4.1 Current meter . 12
4.4.2 Voltage meter . 13
4.5 Luminous flux measurement devices . 13
4.5.1 General . 13
4.5.2 Luminous flux . 13
4.5.3 Sample stage . 15
5 General measuring conditions . 15
5.1 Standard conditions . 15
5.2 Darkroom conditions . 16
5.3 Measurement setup . 16
5.4 Setting the electrical characteristics of measurement devices . 16
5.4.1 Conditions . 16
5.4.2 Current . 16
5.4.3 Voltage . 16
5.4.4 Power . 16
5.4.5 Warm-up time . 17
6 Optical measurement methods . 17
6.1 General . 17
6.2 Conditions . 17
6.3 Perceptual visual quality . 17
6.3.1 General . 17
6.3.2 Procedures . 17
6.4 Lateral and directional scanning configuration . 18
6.4.1 General . 18
6.4.2 Lateral scanning configuration . 18
6.4.3 Directional scanning configuration . 20
6.5 Depth-of-field and depth-of-focus in measurement . 22
6.5.1 General . 22
6.5.2 Front and rear depth-of-field (DoF) . 22
6.5.3 Front and rear depth-of-focus (dof) . 23
6.6 Measurement procedures. 23
6.6.1 General . 23
6.6.2 Cylindrical LS mounting for lateral measurements . 23

6.6.3 Lateral luminance . 24
6.6.4 Lateral luminance uniformity . 24
6.6.5 Lateral chromaticity and chromaticity variation . 25
6.6.6 Directional luminance . 25
6.6.7 Directional luminance variations . 26
6.6.8 Directional chromaticity and chromaticity variation . 26
6.6.9 Luminous flux . 27
7 Precautions . 30
7.1 Remarks . 30
7.2 Further remarks . 31
7.2.1 General . 31
7.2.2 Report . 31
Annex A (informative) Measurement field on the curved light source . 32
A.1 General . 32
A.2 NPLS curvature and measurement field . 32
A.3 MFs on planar, convex and concave cylindrical LSs . 33
Annex B (informative) Planar light source measurement . 35
B.1 General . 35
B.2 Luminance meter and measurement field . 35
Annex C (informative) Contours of light measurement fields on plane, cylindrical
convex, and concave light sources . 36
C.1 General . 36
C.2 MF contour on a non-tilt and tilt planar DUT . 36
C.3 Projection of an MF contour on the outer surface of a cylindrical DUT . 37
Annex D (informative) LMD aperture and inclination angle on a cylindrical light source . 41
D.1 General . 41
D.2 Inclination angle. 41
D.3 Inclination angle variation . 42
D.4 Depth-of-field . 43
D.5 Measurement field size on the cylindrical light source . 45
Bibliography . 50

Figure 1 – Cartesian and spherical coordinate systems for NPLS measurement . 11
Figure 2 – Example of LMD with the observation area surrounding the measurement field . 12
Figure 3 – Current and voltage measurements using an ammeter between points C and

D and a voltage meter between points A and B . 13
Figure 4 – Geometry of 4π-sphere measurement . 14
Figure 5 – Measuring points on convex and concave DUTs based on the setups of
Figure 4 . 15
Figure 6 – Example of a mirror type goniometric system . 15
Figure 7 – Planar LS and cylindrical LS (NPLS) in lateral scanning measurement
arrangements . 19
Figure 8 – Planar LS and cylindrical LS (NPLS) in a directional scanning arrangement . 21
Figure 9 – Pictorial illustration of depth-of-field, depth-of-focus and circle of confusion
for an LMD . 22
Figure 10 – Rear depth-of-field in the measurement setup of a cylindrical light source . 23
Figure A.1 – Schematic diagram of the optical characteristics measurement of planar,
convex and concave cylindrical light source . 32

– 4 – IEC 62595-2-5:2021 © IEC 2021
Figure C.1 – Geometry of intersections of a cone and a plane in non-tilt and tilt
conditions . 36
Figure C.2 – Expanded plane of a cone and intersection lines with tilt and non-tilt

planes (see Figure C.1) . 37
Figure C.3 – Simulated intersections of three planar light sources with a cone
(measurement field
...