Amendment 1 - Organic light emitting diode (OLED) panels for general lighting - Performance requirements

Amendement 1 - Panneaux à diodes électroluminescentes organiques (OLED) destinés à l'éclairage général - Exigences de performance

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IEC 62922
Edition 1.0 2021-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
AM ENDMENT 1
AM ENDEMENT 1
Organic light emitting diode (OLED) panels for general lighting – Performance
requirements
Panneaux à diodes électroluminescentes organiques (OLED) destinés à
l'éclairage général – Exigences de performance
IEC 62922:2016-11/AMD1:2021-08(en-fr)
---------------------- Page: 1 ----------------------
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---------------------- Page: 2 ----------------------
IEC 62922
Edition 1.0 2021-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
AM ENDMENT 1
AM ENDEMENT 1
Organic light emitting diode (OLED) panels for general lighting – Performance
requirements
Panneaux à diodes électroluminescentes organiques (OLED) destinés à
l'éclairage général – Exigences de performance
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.140.99 ISBN 978-2-8322-1013-9

Warning! Make sure that you obtained this publication from an authorized distributor.

Attention! Veuillez vous assurer que vous avez obtenu cette publication via un distributeur agréé.

® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale
---------------------- Page: 3 ----------------------
– 2 – IEC 62922:2016/AMD1:2021
© IEC 2021
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ORGANIC LIGHT EMITTING DIODE (OLED) PANELS FOR
GENERAL LIGHTING – PERFORMANCE REQUIREMENTS
AMENDMENT 1
FOREWORD

1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising

all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international

co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and

in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports,

Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC Publication(s)”). Their

preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with

may participate in this preparatory work. International, governmental and non-governmental organizations liaising

with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for

Standardization (ISO) in accordance with conditions determined by agreement between the two organizations.

2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international

consensus of opinion on the relevant subjects since each technical committee has representation from all

interested IEC National Committees.

3) IEC Publications have the form of recommendations for international use and are accepted by IEC National

Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC

Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any

misinterpretation by any end user.

4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications

transparently to the maximum extent possible in their national and regional publications. Any divergence between

any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter.

5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity

assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any

services carried out by independent certification bodies.

6) All users should ensure that they have the latest edition of this publication.

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members of its technical committees and IEC National Committees for any personal injury, property damage or

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expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC

Publications.

8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is

indispensable for the correct application of this publication.

9) Attention is drawn to the possibility that some of the elements of this document may be the subject of patent

rights. IEC shall not be held responsible for identifying any or all such patent rights.

Amendment 1 to IEC 62922:2016 has been prepared by subcommittee 34A: Electric light

sources, of IEC technical committee 34: Lighting.
The text of this amendment is based on the following documents:
FDIS Report on voting
34A/2241/FDIS 34A/2252/RVD

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 Amendment is English.
---------------------- Page: 4 ----------------------
IEC 62922:2016/AMD1:2021 – 3 –
© IEC 2021

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 IEC are

described in greater detail at www.iec.ch/standardsdev/publications/.

The committee has decided that the contents of this document will remain unchanged until the

stability date indicated on the IEC website under 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.
---------------------- Page: 5 ----------------------
– 4 – IEC 62922:2016/AMD1:2021
© IEC 2021
2 Normative references
Delete the reference to IEC TR 62732.
Replace "ISO 11664-5/CIE S 014-5/E:2009" with "ISO 11664-5/CIE S 014-5/E:2016".
3 Terms and definitions
Add, at the end of 3.5, the following new entries 3.6, 3.7 and 3.8:
3.6
median useful life

length of operating time during which a total of 50 % of a population

of operating OLED tiles or panels of the same type have flux degraded to the luminous flux

maintenance factor x

Note 1 to entry: The median useful life includes operating OLED tiles and panels only.

Note 2 to entry: By convention, the expression "life of OLED tiles" or "life of OLED panels" without any modifiers is

understood to be the median useful life.
3.7
maintained operating voltage

operating voltage measured at an operational time, the OLED tiles

or panels operating under specified conditions

Note 1 to entry: Specified conditions are described either in this document or the manufacturer’s document.

3.8
maintained chromaticity coordinate

chromaticity coordinate measured at an operational time, the OLED

tiles or panels operating under specified conditions

Note 1 to entry: Specified conditions are described either in this document, or the manufacturer’s document.

Note 2 to entry: Details are given in 8.2.2.
5 Marking
5.1 Contents and location
Table 1

Delete the row "Photometric code" and add four new rows before the NOTE, as follows:

---------------------- Page: 6 ----------------------
IEC 62922:2016/AMD1:2021 – 5 –
© IEC 2021
Table 1 – Contents and location of marking
Parameters Location
Rated luminous flux (lm) Mandatory on packaging or product information
Mandatory on packaging or product information
Average luminance (cd/m )

Photometric code (according to IEC TR 62732) Mandatory on packaging or product information

Rated chromaticity coordinates (in u’v’ coordinates) and Mandatory on packaging or product information

chromaticity coordinate range (expressed by Δu’v’, a
u’v’ circle or a u’v’ quadrangle)
Correlated colour temperature (K) Mandatory on packaging or product information
Rated colour rendering index Mandatory on packaging or product information
Operating temperature range (°C) Mandatory on packaging or product information
Rated luminous efficacy (lm/W) Mandatory on packaging or product information
Luminance uniformity (%) Mandatory on packaging or product information
Mandatory on packaging or product information
Luminous intensity distribution

Surface chromaticity uniformity and location of Mandatory on packaging or product information

measurement spots (if applicable)
Angular chromaticity uniformity Mandatory on packaging or product information

Rated location and dimensions of the light output Mandatory on packaging or product information

surface
Rated median useful life (h) Mandatory on packaging or product information
Luminous flux maintenance (%) Mandatory on packaging or product information
Maintained operating voltage (V) Mandatory on packaging or product information
Maintained chromaticity coordinate Mandatory on packaging or product information

NOTE The operating temperature range specifies maximum and minimum temperatures of the OLED panel at

which the OLED panel will function as intended. The operating temperatures are measured according to Annex F.

This requirement is fulfilled if the data file is made available electronically.

7.4 Chromaticity coordinates
Replace the existing text with the following new text:

The chromaticity coordinates shall be determined from the spectral distribution obtained from

the measurement specified in 7.2, in accordance with ISO 11664-5/CIE S 014-5/E:2016.

7.7 Luminance uniformity
Replace the existing title of 7.7 with the following new title:
7.7 Luminance
7.7.1 Average luminance (L )
Replace the existing subclauses 7.7.1.1 to 7.7.1.3 with the following new text:
The initial average luminance is measured in accordance with Annex G.
---------------------- Page: 7 ----------------------
– 6 – IEC 62922:2016/AMD1:2021
© IEC 2021
Compliance:

The initial average luminance shall not deviate from the rated average luminance by more than

10 %.
8 Maintained photometric characteristics
Replace the existing text with the following new Subclauses 8.1 to 8.3:
8.1 Luminous flux maintenance

The luminous flux maintenance factor is obtained from the value at rated life expressed as a

percentage of the initial value.
For the measurement method of luminous flux, Annex C applies.
Information on lifetime estimation is given in Annex H.

An accelerated life test can be used to estimate the lifetime of an OLED light source. If an

accelerated life test is used to estimate the lifetime, then the estimation method with detailed

measurement conditions shall be provided by the manufacturer.

NOTE 1 The luminous flux at the rated life can be evaluated by the direct measurement or estimation.

NOTE 2 For general guidance on LED product lifetime metrics, see Annex C of IEC 62717:2014 and Annex C of

IEC 62717:2014/AMD2:2019.
Compliance:

The evaluated luminous flux maintenance factor at rated life time shall not be less than 90 %

of the rated luminous flux maintenance factor.
8.2 Maintained operating voltage

The manufacturer shall declare the maintained operating voltage values for 2 000 h and the

maximum operating voltage value for OLED light sources during their lifetime.

An OLED panel shall not exceed the maintained operating voltage rise, which is defined by its

manufacturer.
Compliance:

The maintained operating voltage of the OLED panels measured at 2 000 h shall not exceed

the declared value.
8.3 Maintained chromaticity coordinates

The initial chromaticity coordinates of the OLED panel and the chromaticity coordinates at

2 000 h are measured.
NOTE The maintained chromaticity coordinate shift can be expressed by Δ(u’,v’).
Compliance:

The OLED panel shall not exceed the rated maintained chromaticity coordinate shift.

---------------------- Page: 8 ----------------------
IEC 62922:2016/AMD1:2021 – 7 –
© IEC 2021
9.2 High temperature – high humidity storage
Replace the existing text with the following new text:

An OLED panel shall be kept in a humidity cabinet having a relative humidity of (90 ± 5) % for

500 h. The temperature of internal air shall be maintained at (60 ± 2) °C. The OLED panel shall

be placed in the humidity cabinet where humidity and temperature are maintained without

supplying electricity. The test shall be conducted so that no condensation or water droplets

appear on any part of the OLED panel. After the high temperature – high humidity storage test,

the luminous flux and chromaticity of the OLED panel are measured in accordance with 7.2 and

7.4 respectively. The mounting position shall be declared in the test report.
10 Information for controlgear design
Replace the existing text with the following new text:

Information for controlgear design is given in Annex E. This should be followed for proper

operation of OLED panels.
---------------------- Page: 9 ----------------------
– 8 – IEC 62922:2016/AMD1:2021
© IEC 2021
At the end of Annex F, add the following new Annex G and Annex H:
Annex G
(normative)
Measuring method for average luminance
G.1 General

Measurement of the average luminance of an OLED panel shall use one of the two methods

described below.
1) imaging luminance measuring device (ILMD) method;
2) spot luminance meter method.
The actual method used for measurement shall be recorded in the test report.
G.2 Setting

Depending on the method adopted, it may be necessary to install the panel vertically to keep

an adequate distance between the panel and the instrument. In this case, the vertical mounting

position shall be recorded in the test report.
G.3 Imaging luminance measuring device (ILMD) method

The average luminance shall be calculated from an image of the entire light output surface with

a maximum exclusion zone of 3 mm from the edge.
G.4 Spot luminance meter method

The measurement of average luminance (L ) shall be carried out in perpendicular direction to

the light output surface of an OLED panel. The distance from the edge of the light output surface

to the closest measurement spot perimeter shall be a maximum of 3 mm.

The remaining lighting area shall then be subdivided into quadrilateral areas with a side length

corresponding to a viewing angle of not more than 1° at a viewing distance of 1 m. The spot

size shall fit into the quadrilateral area with a clearance of at least 1 mm.
EXAMPLE For a 1° viewing angle, the side length l of a subdivision is given by

l = tan (0,5°) × 2 × 1 m = 0,017 m = 1,7 cm. So a 10 cm × 10 cm lighting area would have to be divided into

10/1,7 ≈ 5,8, i. e. 5 × 5 segments.

The arithmetic average of all luminance values of the measured areas is taken as the initial

average luminance.
---------------------- Page: 10 ----------------------
IEC 62922:2016/AMD1:2021 – 9 –
© IEC 2021
Annex H
(informative)
Information on lifetime estimation
H.1 General

A direct measurement of the median useful life, L , of an OLED light source operating at rated

electrical conditions can take tens of thousands of hours. Therefore, accelerated life tests are

used to reduce the necessary testing time for an estimation of the median useful life.

The physical mechanisms for luminous flux degradation differ substantially between OLED

products from different designs and manufacturing processes. Thus, a single standardized

mathematical model for the luminous flux degradation is not known or expected for OLED

technology today.

This annex gives guidance on various tests for OLED lifetime estimation that do not require

testing to the full median useful life.
H.2 Extrapolation through the deterioration curve fitting

The objective of this method is to use degradation measurements taken under the rated

electrical conditions and before reaching L to determine the functional parameters.

The majority part of the degradation curve of OLED panels can be expressed in a Weibull

degradation mode (Equation (H.1)).

The luminous flux maintenance can be represented over elapsed time t by the Weibull reliability

function, R(t),
R(t) = exp(−(t/t ) ) (H.1)
where t is the time scaling factor and β is the shape factor.

Some of the degradation curves of OLED panels can be expressed with the combination of the

initial degradation (first term) and the normal degradation (second term).
R(t) = a∙exp(−(t/t )) + (1 − a)exp(−(t/t ) ) (H.2)
1 0
0 ≦ a < 1

where t is the time scaling factor of the initial degradation and 𝑎𝑎 is the proportion factor of the

initial degradation.

NOTE In 2014, the group who proposed this Annex H (Chemical Materials Evaluation and Research Base) reported

that about 3 % of data cannot be fitted by stretched-exponential decay (SED) function (Weibull reliability function)

(Equation (1)) [T. Yoshioka et al. SID Symposium Digest, 45, 642 (2014)]. And there is a document which expresses

that stretched-exponential decay (SED) function does not have a reaction kinetics meaning and is expressed by

several Arrhenius equations [T. Yoshioka et al. SID Symposium Digest, 46, 1650 (2015)]. Therefore, the fitting

equations are not restricted to one form in order to express OLED degradation data in the current situation.

Most OLED panels are fitted by Equation (H.1). Some panels with fair initial degradation are

fitted by Equation (H.2).
---------------------- Page: 11 ----------------------
– 10 – IEC 62922:2016/AMD1:2021
© IEC 2021
EXAMPLE

In this example degradation data was collected frequently over a period of 500 h. The data was fitted using

Equation (H.1). A best fit to the parameters was obtained for β = 0,8 and t = 8 000 h. An estimation of the median

useful life for 70 % luminous flux maintenance is calculated using the fitted function as 2 200 h (see Figure H.1).

NOTE The extrapolation value (□) of L is obtained by using the deterioration curve data (○) and the extrapolation

curve (dashed line). The time is 2 200 h when the luminous flux maintenance ratio becomes 70 % (L ).

Figure H.1 – Typical degradation curve of acceleration test

The estimation accuracy of the median useful life, L , improves considerably as more data is

taken over a longer period.
H.3 Lifetime estimation using accelerated testing

The time required for lifetime estimation may be shortened by conducting an accelerated test,

which speeds up the degradation process of an OLED product by subjecting it to higher stress

conditions of temperature or drive current or both. Extrapolation to normal operating conditions

of temperature and drive current is used to estimate the median useful life.

Test samples for an accelerated test should be selected from a population of OLED products

having the same degradation characteristics. Normally this will be from a normal manufacturing

production run. At least three test samples should be tested for each selected stress condition.

The accelerated test should be designed so as to avoid changing the failure or degradation

mode at all levels of stress conditions, especially high temperature and high drive current for

OLED panels. A lack of fit to the same degradation function at all stress levels may be evidence

of a changing degradation physics. Test samples should maintain uniform current density at all

stress levels. Heating characteristics may differ due to self-heating either by conduction (joule

heating) or radiation from the test piece resulting in a non-uniform current density distribution.

If evidence of an altered degradation mode is observed, either by visual inspection of test

samples or by lack of fit analysis, then the results should not be used to estimate the median

useful life.

The time required for significant degradation of the test samples subjected to the lowest stress

level will normally be longer than for the higher stress levels. However, estimates of the median

useful life are possible as soon as the data fits the accelerated life test model reasonably well.

---------------------- Page: 12 ----------------------
IEC 62922:2016/AMD1:2021 – 11 –
© IEC 2021
H.4 Life estimation using the acceleration factor

This method uses complete acceleration test data for a shorter time (e.g. L or L ) to estimate

99 90

an acceleration factor which is then applied to complete data at the high stress level lifetime

(L ) to estimate the median useful life (L ) in normal operation. Either acceleration stress,

70 70

drive current or temperature, can be used. However, the same acceleration stress, type and

level, should be used for all test pieces. If the data at the same acceleration stress is not

available, then this method should not be used.

The estimated acceleration factor is calculated by dividing the measured lifetime (e.g. L ) at

normal operation by the same measured lifetime (e.g. L ) with accelerated stress.

EXAMPLE
Normal: L = 100 h, Accelerated: L = 10 h
99 99
Normal: L = 500 h, Accelerated: L = 50 h
90 90
Acceleration factor = 100/10 = 500/50 = 10 for each lifetime.

When the test pieces at the accelerated stress level reach the rated median useful life, L

then the acceleration factor can be used to estimate the L life in normal operation. Continuing

the example, if L at the accelerated condition is 200 h and the accelerated factor is 10, then

L in normal operation is 2 000 h.
H.5 Extrapolation of lifetime using current acceleration data

This method uses complete acceleration test data at two or more acceleration stress levels of

drive current and fits a power function, Equation (H.3), for the measured median useful life, L ,

as a function of the stress drive current, I ,
L = L · (I /I ) (H.3)
x 0 d 0

where I is the rated drive current in normal operation, and the fitted parameters are L and α.

0 0

The current multiplication factor is defined as the ratio, I /I , for convenience when plotting the

d 0

data on a double logarithmic plot and fitting with a straight line. The median useful life for

operation at the rated drive current is estimated at a current multiplication factor equal to

1 (I = I ).
d 0

As an example, consider accelerated test data in which L is measured at three accelerated

drive currents with current multiplication factors as follows:
L = 80 h; at I /I = 5
70 d 0
L = 125 h; at I /I = 4
70 d 0
L = 222 h; at I /I = 3
70 d 0

The data of this example is plotted in Figure H.2. The fitted function parameters are α = 2 and

L = 2 000 h. Thus, the estimated median useful life at rated drive current is L = 2 000 h

0 70
shown as the open square symbol in Figure H.2.
---------------------- Page: 13 ----------------------
– 12 – IEC 62922:2016/AMD1:2021
© IEC 2021
Figure H.2 – Dependence of L on the driving current
H.6 Extrapolation of lifetime using current and temperature acceleration data

This method uses complete acceleration test data at two or more acceleration stress levels of

drive current and temperature. A full or half fraction factorial test design at three levels of drive

current and temperature with replication is recommended. Then the degradation data collected

at each stress condition is fitted to a Weibull reliability function, R(t), using Equation (H.1).

The fitted shape parameters, β, should have nearly the same value indicating a consistent

physical degradation mode. An average β value should be used in the equation for estimating

median useful life, see Equation (H.6). If the shape parameter, β, varies significantly between

stress conditions, then this method should not be used. The fitted time scale parameters, t ,

should vary with stress conditions and are subsequently fitted to a power function for the drive

current, I , and an Arrhenius function for the OLED panel temperature, T , using
d EL
Equation (H.4),
t (T ,I ) = A∙(I /I ) ∙exp(E /(k ∙T ) (H.4)
0 EL d d 0 a B EL

where I is the rated drive current in normal operation, A and α are the fitted time parameter

and power function exponent respectively, E is the fitted activation energy parameter, and k

a B
is the Boltzmann constant (8,617 × 10 eV/K).

The OLED panel temperature, T , is related to the ambient temperature, T , and the

EL amb
temperature rise, ΔT , due to self-heating of the OLED device by Equation (H.5),
T = T + ΔT (H.5)
EL amb sh
Temperature values for Equations (H.3) and (H.4) are in Kelvin.
---------------------- Page: 14 ----------------------
IEC 62922:2016/AMD1:2021 – 13 –
© IEC 2021

The median useful life for normal operation at rated drive current, I , and OLED device

temperature, T , is estimated using the calculated time scale parameter, t (T ,I ), and

stack 0 stack 0
the average shape value, β, using Equation (H.6),
(1.β)
L = t · (ln(100/x)) (H.6)
x 0
where x is the luminous
...

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