IEC 62922:2016/AMD1:2021

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)

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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

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.140.99 ISBN 978-2-8322-1013-9

– 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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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.

© 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.
– 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
L
x
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:

© 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
a
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.
a
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 )
av
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.

– 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.

© 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.
– 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
av
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.
© 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
x
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.
x
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),
β
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).
β
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).
– 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
x
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.

© 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 ,
x
as a function of the stress drive current, I ,
d
α
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.

– 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),
α
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
−5
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),
sh
T = T + ΔT (H.5)
EL amb sh
Temperature values for Equations (H.3) and (H.4) are in Kelvin.

© 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 flux maintenance factor.
The following illustrated example of this method is provided for additional guidance. Five
acceleration stress conditions are tested.
Condition 1: I /I = 10, T = 298 K
d 0 amb
Condition 2: I /I = 10, T = 313 K
d 0 amb
Condition 3: I /I = 10, T = 328 K
d 0 amb
Condition 4: I /I = 7, T = 328 K
d 0 amb
Condition 5: I /I = 5, T = 328 K
d 0 amb
NOTE The recommendation for a factorial test design has not been followed in this example.
Luminous flux degradation data for each condition is fitted to the Weibull reliability function, R(t),
using Equation (H.1). The following fitted parameter values are calculated.
Condition 1: t = 718 h, β = 0,71
Condition 2: t = 411 h, β = 0,70
Condition 3: t = 229 h, β = 0,71
Condition 4: t = 387 h, β = 0,69
Condition 5: t = 646 h, β = 0,69
The variation in the fitted shape parameters is small indicating a consistent physical degradation
mode, thus the average β = 0,70 will be used in the median useful life estimation.
The time scale parameter, t , is fitted using Equation (H.3), the drive currents, I , and the OLED
0 d
device temperatures, T , adjusted for self-heating (not presented) by Equation (H.5). The fitted
EL
parameters for this example were as follows:
E = 0,36 eV
a
α = 1,24
A = 0,022 h
Figure H.3 a) shows an Arrhenius plot of the time scale (t ) data versus reciprocal temperature
(1/(k · T )) for conditions 1, 2 and 3. The slope of the line estimates the activation energy, E .
B EL a
Figure H.3 b) shows a plot of the time scale data adjusted for temperature (t /exp(E /k · T ))
0 a B EL
versus the current multiplication factor (I /I ) for conditions 3, 4 and 5. The slope of this line
d 0
estimates the power function exponent, α.
For normal operation at rated drive current, ambient temperature, T = 298 K and OLED
amb
device temperature, T = 306 K, the time scale parameter is estimated to be t = 18 485 h.
EL 0
Using this t , the average shape parameter, β = 0,7, and a luminous flux maintenance factor,
x = 70, in Equation (H.6), the median useful life at 70 % maintained luminous flux is estimated
as L = 4 167 h for normal operating conditions.
– 14 – IEC 62922:2016/AMD1:2021
© IEC 2021
a) Arrhenius plot of t b) Current dependence of t
0 0
Figure H.3 – Arrhenius plot and power function
Figure H.4 shows the fitted functions for the time scale parameter, t , and median useful life at
70 % maintained luminous flux, L overlaid on the data for each stress condition.
a) Current dependence of t b) Current dependence of L
0 70
Figure H.4 – Current dependence of t and L
0 70
By using the accelerated data (plots symbolled with O), t and L for any operation condition
0 70
by using Equations (H.3) and (H.4), T = 298 K (solid line), T = 313 K (dotted line) and
amb amb
T = 328 K (slashed line). T and L at rated operation condition are shown by Figure H.4.
amb 0 70
© IEC 2021
Bibliography
Add the following new references:
IEC 62717:2014, LED modules for general lighting – Performance requirements
IEC 62717:2014/AMD1:2015
IEC 62717:2014/AMD2:2019
T. Yoshioka, K. Sugimoto, K. Katagi, Y. Kitago, M. Tajima, S. Miyaguchi, T. Tsutsui, R. Iwasaki,
Y. Furukawa, "An
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