IEC 62595-2-2:2018

IEC 62595-2-2 ®
Edition 1.0 2018-02
INTERNATIONAL
STANDARD
colour
inside
Display lighting unit –
Part 2-2: Measuring methods of LED light bars used in LCD BLUs
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IEC 62595-2-2 ®
Edition 1.0 2018-02
INTERNATIONAL
STANDARD
colour
inside
Display lighting unit –
Part 2-2: Measuring methods of LED light bars used in LCD BLUs

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 31.120; 31.260 ISBN 978-2-8322-5338-0

– 2 – IEC 62595-2-2:2018 © IEC 2018
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 . 6
3.3 Letter symbols (quantity symbols/unit symbols) . 7
4 Measuring configuration . 7
4.1 General . 7
4.2 Light measuring device (LMD) . 8
4.2.1 Luminance meter . 8
4.2.2 Spectroradiometer . 8
4.2.3 Colorimeter . 8
4.3 Sample stage . 9
5 Measuring conditions . 9
5.1 Standard measuring conditions . 9
5.2 Electrical driving conditions. 9
5.3 Warm-up time . 9
5.4 Dark room conditions . 9
5.5 Standard thermal conditions . 9
5.6 Setting conditions . 9
5.7 Mechanical alignment condition . 9
6 Measuring methods . 10
6.1 Electrical parameters . 10
6.1.1 Purpose . 10
6.1.2 Measuring conditions . 10
6.1.3 Measuring method . 10
6.2 Luminance distribution profile . 10
6.2.1 Purpose . 10
6.2.2 Measuring conditions . 10
6.2.3 Measuring method . 10
6.2.4 Report . 12
6.3 Chromaticity and colour uniformity . 13
6.3.1 Purpose . 13
6.3.2 Measuring conditions . 13
6.3.3 Measuring method . 13
6.3.4 Report . 13
7 Test report . 14
Bibliography . 15

Figure 1 – Example of measuring system and arrangement for LED light bar . 8
Figure 2 – Example of LED light bar set and mechanical origin alignment . 10
Figure 3 – Example of 2D luminance distribution on the diffuser plate with lit LED light
bar . 11

Figure 4 – Example of the luminance distribution profiles along the x- and y-axes . 12
Figure 5 – Example of the luminance distribution profiles along the x–axis, L (x, 0) . 12
v
Table 1 – Letter symbols (quantity symbols/unit symbols) . 7

– 4 – IEC 62595-2-2:2018 © IEC 2018
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
DISPLAY LIGHTING UNIT –
Part 2-2: Measuring methods of LED light bars used in LCD BLUs

FOREWORD
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International Standard IEC 62595-2-2 has been prepared by IEC technical committee 110:
Electronic display devices.
The text of this International Standard is based on the following documents:
CDV Report on voting
110/890/CDV 110/932A/RVC
Full information on the voting for the approval of this International Standard can be found in
the report on voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts in the IEC 62595 series, published under the general title Display lighting
unit, 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 "http://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.
A bilingual version of this publication may be issued at a later date.

IMPORTANT – The 'colour inside' logo on the cover page of this publication 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.
– 6 – IEC 62595-2-2:2018 © IEC 2018
DISPLAY LIGHTING UNIT –
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