IEC 62341-1-2:2014

IEC 62341-1-2 ®
Edition 2.0 2014-04
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Organic light emitting diode (OLED) displays –
Part 1-2: Terminology and letter symbols

Afficheurs à diodes électroluminescentes organiques (OLED) –
Partie 1-2: Terminologie et symboles littéraux

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IEC 62341-1-2 ®
Edition 2.0 2014-04
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Organic light emitting diode (OLED) displays –

Part 1-2: Terminology and letter symbols

Afficheurs à diodes électroluminescentes organiques (OLED) –

Partie 1-2: Terminologie et symboles littéraux

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX U
ICS 31.260 ISBN 978-2-8322-1512-8

– 2 – IEC 62341-1-2:2014  IEC 2014
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Terms and definitions . 5
2.1 Classification of terms . 5
2.2 Fundamental terms . 5
2.3 Terms related to physical properties . 9
2.4 Terms related to constructive elements . 10
2.5 Terms related to performances and specifications. 15
2.6 Terms related to the production process . 21
3 Letter symbols (quantity symbols/unit symbols) . 21
3.1 Classification . 21
3.2 Letter symbols . 22
Annex A (normative) Supplement to terms . 24
A.1 Pixel pitch . 24
A.2 Viewing direction . 25
Annex B (informative) Structure of an OLED . 26
Bibliography . 27

Figure A.1 – Pixel pitch . 24
Figure A.2 – Viewing direction . 25
Figure B.1 – An example of an OLED structure . 26

Table 1 – Fundamental symbols . 22
Table 2 – Symbols related to physical properties . 22
Table 3 – Symbol related to constructive elements . 22
Table 4 – Symbols related to performances and specifications . 22

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ORGANIC LIGHT EMITTING DIODE (OLED) DISPLAYS –

Part 1-2: Terminology and letter symbols

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
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patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 62341-1-2 has been prepared by IEC technical committee 110:
Electronic display devices.
This second edition cancels and replaces the first edition published in 2007. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) Additional terms were added in Clause 2.
b) Several terms were deleted from Clause 2.
c) The definition of several terms was revised in Clause 2.
d) Annex B is added as informative part.
e) The new edition was editorially changed according with the current ISO/IEC directives.

– 4 – IEC 62341-1-2:2014  IEC 2014
The text of this standard is based on the following documents:
CDV Report on voting
110/465/CDV 110/520A/RVC
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all the parts in the IEC 62341 series, under the general title Organic light emitting
diode (OLED) displays, can be found on the IEC website.
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC web site under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
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.
ORGANIC LIGHT EMITTING DIODE (OLED) DISPLAYS –

Part 1-2: Terminology and letter symbols

1 Scope
This part of IEC 62341 gives the preferred terms, their definitions and symbols for organic
light emitting diode (OLED) displays, with the object of using the same terminology when
publications are prepared in different countries.
2 Terms and definitions
For purposes of this document, the following terms and definitions apply.
2.1 Classification of terms
Terms for organic light emitting diode (OLED) displays are classified as follows:
a) fundamental terms (2.2)
b) terms related to physical properties (2.3)
c) terms related to constructive elements (2.4)
d) terms related to performances and specifications (2.5)
e) terms related to the production process (2.6)
2.2 Fundamental terms
2.2.1
active matrix driving
active addressed driving
matrix driving method in which each pixel or subpixel has at least one active switching (e.g.
diode or transistor) and storage element
2.2.2
addressing method
method of selecting each pixel or subpixel for activation
2.2.3
alphanumeric display
display that is able to show a limited set of characters comprising at least letters and Arabic
numerals
2.2.4
area-colour display
zone-colour display
display in which the display panel is partitioned into several parts, each one showing a colour
different from each other
2.2.5
bottom emission
device structure, in which almost all light emitted passes through a substrate on which organic
electroluminescent layers are made

– 6 – IEC 62341-1-2:2014  IEC 2014
2.2.6
constant-current driving
driving method where a constant current is applied to each pixel or subpixel
2.2.7
constant-voltage driving
driving method where a constant voltage is applied to each pixel or subpixel
2.2.8
display with a bright background
display showing dark images on a bright background
2.2.9
display with a dark background
display showing bright images on a dark background
2.2.10
doping method
method of adding a small quantity of different material to the host material
Note 1 to entry: This method is used in order to improve the device characteristics or to change the emission
spectrum.
2.2.11
driving method
specific method for activating each pixel or subpixel
2.2.12
dual emission display
display in which light is emitted from both sides (top and bottom) of a substrate on which
organic electroluminescent layers are made
2.2.13
emissive display
display that uses light generation to produce visual information (electro-luminescence, photo-
luminescence, etc.)
2.2.14
flexible display
display that is mechanically flexible
2.2.15
full-colour display
display capable of showing at least 3 primary colours, the colour gamut of which includes a
white area (e.g. containing D50, D65, D75) and having at least a 64 grey scale per primary
2.2.16
hybrid organic light emitting diode
hybrid OLED
OLED that uses more than one kind of material and/or processing method
Note 1 to entry: A hybrid OLED can be as follows, for example:
a) an OLED which contains fluorescent and phosphorescent emitters,
b) an OLED which contains polymer and small molecule layers.

2.2.17
inverted organic light emitting diode
inverted OLED
OLED where the substrate carries the cathode
2.2.18
matrix display
display device consisting of regularly distributed pixels arranged in rows and columns
2.2.19
molecular organic light emitting diode display
organic light emitting diode display composed of organic (small) molecules
2.2.20
monochrome display
display capable of reproducing only one colour
2.2.21
multi-colour display
display other than monochrome display and full-colour display
2.2.22
multiplex driving
driving method of time-share driving in which one common electrode is addressed to more
than two pixels or subpixels
2.2.23
organic electroluminescence
OEL
emission from organic materials by recombination of negatively and positively charged
carriers when forward electric bias is applied
Note 1 to entry: This note applies to the French language only.
2.2.24
organic electroluminescent display
OEL display
display showing visual information using organic electroluminescence
2.2.25
organic light emitting diode
OLED
light emitting diode in which light is emitted from organic materials
Note 1 to entry: This note applies to the French language only.
2.2.26
organic light emitting diode display
OLED display
display incorporating organic light emitting diodes
2.2.27
organic light emitting diode display module
organic light emitting diode display panel, its driving electronics and optical films if used in the
device design
– 8 – IEC 62341-1-2:2014  IEC 2014
2.2.28
organic light emitting diode panel
organic light emitting diode display panel
display panel of an organic light emitting diode display without external drivers
2.2.29
passive matrix addressing
matrix driving method in which each pixel or subpixel is addressed directly by applied signals
on the addressing and data lines
2.2.30
PIN organic light emitting diode
OLED incorporating conductivity doping
Note 1 to entry: See “p-HTL” and “n-ETL”.
2.2.31
polymer organic light emitting diode
light emitting diode in which light is emitted from polymeric materials
Note 1 to entry: The term “polymer light emitting diode” is sometimes used.
2.2.32
segment display
display device showing fixed patterns made of segment electrodes which may be different in
size and orientation
2.2.33
stacked organic light emitting diode
stacked OLED
tandem organic light emitting diode
tandem OLED
at least two single OLED units stacked on top of each other
Note 1 to entry: The interface between the single OLED unit is not formed by an anode and a cathode pair, but by a
charge generation layer.
2.2.34
standard light source
light source that approximates a defined illuminant, such as CIE illuminant A and D65
2.2.35
standard reference atmosphere
reference atmospheric conditions used for standardizing the data measured under different
atmospheric conditions
2.2.36
static driving
method of driving in which all pixels are activated simultaneously and constantly
2.2.37
top emission
device structure, in which almost all the light is emitted (toward) outside from a (top) side of a
substrate, on which the OLED device is formed
2.2.38
transparent display
display in which the display area is visibly transparent

2.3 Terms related to physical properties
2.3.1
charge carrier density
density of mobile electrons and/or holes in a material
–3
Note 1 to entry: Expressed in cm .
2.3.2
crystallization temperature
temperature at which the material changes into a crystalline state when it is cooled from a
liquid state, molten state or solution form
Note 1 to entry: In the case of an amorphous material, the temperature at which the material changes into partly
or wholly crystalline state.
2.3.3
electroluminescence spectrum
spectral distribution of the light emitted by the process of electroluminescence
2.3.4
emission ratio
ratio of the two averaged luminance values on two sides of the OLED
Note 1 to entry: The ratio is given in a normalised form, stating the bigger value first. The smaller value is
normalised to unity.
2.3.5
external quantum efficiency
ratio of the number of the photons emitted from an organic light emitting diode divided by the
number of the injected electrons or holes
Note 1 to entry: An external quantum efficiency is indicated as a product of an internal quantum efficiency and an
external light out-coupling efficiency.
2.3.6
fluorescence yield
fluorescence yield efficiency
ratio of the number of fluorescent photons divided by the number of photons absorbed into the
material
2.3.7
fluorescence
emission of light from an excited singlet state of materials
2.3.8
injection barrier
energy barrier of the carrier injection at the interface of an organic layer and another organic
layer or at the interface of an organic layer and an electrode
2.3.9
internal quantum efficiency
ratio of the number of the photons produced from the electric charges injected from the
electrode divided by the number of the injected electrons or holes
Note 1 to entry: An internal quantum efficiency is indicated as a product of a recombination probability of
electrons and holes, as an efficiency of exciton generation through carrier recombination and as an efficiency of
photon generation from exciton.

– 10 – IEC 62341-1-2:2014  IEC 2014
2.3.10
optical axis
distinct direction in optically anisotropic materials and elements, e.g. polarizers, wave plates
and retarders
2.3.11
phosphorescence yield
phosphorescence yield efficiency
ratio of the number of phosphorescent photons divided by the number of photons absorbed
into the material
2.3.12
phosphorescence
emission of light from an excited triplet state of materials
2.3.13
photoluminescence spectrum
spectral distribution of the light emitted from materials excited by the light of wavelengths
shorter than that of the photoluminescent emission
2.4 Terms related to constructive elements
2.4.1
amorphous silicon
solid state silicon without a distinct crystalline structure
Note 1 to entry: The carrier mobility is rather low compared with polycrystalline silicon.
2.4.2
anode separator
rib to electrically separate each anode from the adjacent anode in a passive matrix organic
light emitting diode display panel
2.4.3
bank
raised elevation that is fabricated around each pixel or subpixel
Note 1 to entry: Generally, it is used to prevent overflowing of the coated solution.
2.4.4
black matrix
film-like structure that absorbs ambient or internally scattered light
2.4.5
buffer layer
layer inserted in the device structure which may be used, for example, to improve current
injection or reduce surface roughness
2.4.6
cathode separator
rib to electrically separate each cathode from the adjacent cathode in a passive matrix
organic light emitting diode display panel
2.4.7
charge generation layer
CGL
layer in a stacked OLED which generates electrons for one adjacent OLED unit (acting as a
cathode) and holes for a second adjacent OLED unit (acting as an anode)

Note 1 to entry: The CGL is not directly connected to an electrical power supply.
Note 2 to entry: This note applies to the French language only.
2.4.8
circular polarizer
optical component consisting of a linear polarizer and 1/4-wavelength retarder plate which
transforms the component of incoming light parallel to the polarizer, into circularly polarized
light
2.4.9
colour changing medium
medium containing fluorescent dyes that absorb the emission energy of organic electro-
luminescence and re-emit photons with longer wavelength than the absorbed photons
2.4.10
colour filter
regularly transmitting device used to modify the radiant or luminous flux, the relative spectral
distribution, or both, of the radiation passing through it
Note 1 to entry: Generally, it is used as 3-primary-colour (red, green, blue) filters with white organic light emitting
diode for colour image display or as a filter to improve the colour saturation of an organic light emitting diode.
2.4.11
common electrode
2.4.11.1
common electrode
electrode connected to all segments
2.4.11.2
common electrode
row- or column- scanning electrode
2.4.11.3
common electrode
electrode connecting all pixels in a row and/or a column
2.4.12
data electrode
electrode driven by the data signal voltage or current synchronized with the scanning signals
in a multiplexed display
2.4.13
dopant
different materials added to the host material in small quantity to improve the device
characteristics such as enhancement of luminous efficiency, spectrum change of emission,
and decreasing of resistance
2.4.14
dot electrode
discrete electrode for each pixel or subpixel in an active matrix display, which is separated
from the data electrode line by a switching device such as a thin film transistor
2.4.15
driver
circuits that supply signal- and scanning voltages and/or currents to a display panel
Note 1 to entry: There are two types of drivers, a scanning electrode (row electrode) driver and a data electrode
(column electrode) driver, in a matrix display.

– 12 – IEC 62341-1-2:2014  IEC 2014
2.4.16
encapsulation
enclosing device/structure to protect the organic layers and the electrodes from humidity
and/or oxygen
2.4.17
encapsulation glass
cover glass
glass to protect the organic layer and the electrodes from humidity and/or oxygen
2.4.18
exciton blocking layer
organic layer with a wide energy band gap that blocks exciton diffusion, usually incorporated
in an organic light emitting diode for confining triplet excitons in a light emitting layer
2.4.19
external outcoupling structures
optical outcoupling structures which are located on the outer substrate surface to extract more
light from the substrate into the air
2.4.20
gate electrode
electrode which controls or connects with a gate terminal of a transistor in an active matrix-
addressed display
2.4.21
getter
material that helps maintain vacuum by chemically adsorbing gases outgassing from the
surfaces in vacuum
2.4.22
p-doped hole transport layer
p-HTL
electrically doped hole transport layer for further conductivity increase
Note 1 to entry: This note applies to the French language only.
2.4.23
n-doped electron transport layer
n-ETL
electrically doped electron transport layer for further conductivity increase
Note 1 to entry: This note applies to the French language only.
2.4.24
host material
material that provides a mechanical/electrical matrix for the dopants
2.4.25
insulating layer
insulator formed below the cathode separator to prevent an electrical short between anodes
and cathodes
2.4.26
interlayer
2.4.26.1
interlayer
ITL
layer which serves to separate the fluorescent from the
phosphorescent emission zone
Note 1 to entry: This note applies to the French language only.
2.4.26.2
interlayer
ITL
layer which separates emission layers and carrier injection layers
Note 1 to entry: This note applies to the French language only.
2.4.27
internal outcoupling structures
optical outcoupling structures which are located between the OLED stack and the substrate to
bring more light into the substrate which finally leads to a higher amount of photons extracted
into the air
2.4.28
low temperature polysilicon
LTPS
poly crystalline silicon fabricated at a substrate temperature below 450 °C
Note 1 to entry: This note applies to the French language only.
2.4.29
microlens
microlens array
optical lenses fabricated close to pixels in order to enhance the out-coupling efficiency of
emission
2.4.30
molecular material
organic materials used for an organic light emitting diode, often indicating organic materials
with molecular weight of less than 2 000
Note 1 to entry: Different molecular materials are used for carrier injection, carrier transport, and emission in a
multilayer form.
2.4.31
multi-layer organic structure
structure that has multiple organic layers to improve emission efficiency
Note 1 to entry: Each layer has one or more functions, such as electron transport, emission or hole transport.
2.4.32
OLED controller
electric device that supplies control signal voltages, e.g. timing signals, to operate driving ICs
Note 1 to entry: It may process display signals such as analogue-to-digital (A/D) and/or digital-to-analogue (D/A)
signal conversion. An IC for controller is called controller-IC.
2.4.33
optical outcoupling structures
optical structures to enhance the light extraction from the OLED to the air

– 14 – IEC 62341-1-2:2014  IEC 2014
2.4.34
panel substrate
supporting material, generally transparent, made of e.g. glass or plastic sheet on which the
electrodes, wiring, and organic layers of an organic light emitting diode display panel are
formed
2.4.35
passivation
method to protect the organic layers and the electrodes from humidity and/or oxygen
2.4.36
polymer material
organic materials used for an organic light emitting diode, this term often indicates organic
materials with molecular weight of higher than 10 000
Note 1 to entry: Different polymer materials are used for carrier injection, carrier transport, and emission in a
multiplayer form.
2.4.37
protection sheet
plastic sheet that protects a display panel surface from mechanical harm during fabrication
and/or shipment of an organic light emitting diode display
2.4.38
scanning electrode
electrode connected to the scanning signal in a matrix display
2.4.39
sealant
adhesive for encapsulation
2.4.40
segment electrode
2.4.40.1
segment electrode
electrode forming a part of alphanumeric characters and/or fixed patterns
in a segment display
2.4.40.2
segment electrode
data or signal electrode
2.4.41
single layer structure
structure of an organic light emitting diode, that has a single organic layer
Note 1 to entry: The single layer has all the functions such as electron transport, emission or hole transport.
2.4.42
source electrode
electrode which connects with a source terminal of a transistor in an active matrix display
2.4.43
storage capacitor
capacitor keeping a gate voltage of driving TFT to maintain a certain luminance of each pixel
or subpixel in an active matrix display

2.4.44
substrate
bare sheet material used as the base structural element to make an organic light emitting
diode display
Note 1 to entry: This is commonly glass material but Si wafer or plastics are also used.
2.4.45
thin film diode
TFD
diode formed on the surface of a substrate as a thin film
Note 1 to entry: This note applies to the French language only.
2.4.46
thin film transistor
TFT
transistor formed on the surface of a substrate as a thin film
Note 1 to entry: This note applies to the French language only.
2.4.47
transparent conductive layer
layer that has both electric conductivity and transmission of light
Note 1 to entry: A typical material is ITO (indium tin oxide).
2.4.48
transparent electrode
electrode that has both electric conductivity and transmission of light
Note 1 to entry: A typical material is ITO (indium tin oxide).
2.5 Terms related to performances and specifications
2.5.1
acceleration coefficient
ratio of the lifetime of an organic light emitting diode under normal use and the lifetime under
accelerated conditions
2.5.2
accelerated test
test under accelerating conditions to estimate the operational lifetime within a short time
2.5.3
active area
area that has a display function of the display device
2.5.4
addressability
number of pixels in the horizontal and vertical directions that can have their luminance and
chromaticity changed
Note 1 to entry: Usually expressed in the number of horizontal pixels by the number of vertical pixels. This term is
not synonymous with resolution.
2.5.5
afterimage
image retention
phenomenon in which an image of the previous display persists for a short time after display
switching
– 16 – IEC 62341-1-2:2014  IEC 2014
2.5.6
amplitude modulation
method for generating grey scale by modulation of the amplitude of the driving voltage/current
at constant pulse width
2.5.7
anti-reflection
treatment performed on a surface to eliminate the reflected light from an interface with
multiple layers by coating of a film which has different refractive indexes
2.5.8
aperture ratio
ratio of the pixel area available for light modulation or light emission to the total geometrical
pixel area
Note 1 to entry: Fill factor has the same meaning.
2.5.9
bezel opening area
all the area surrounded by a bezel that can be recognized in an organic light emitting diode
display
2.5.10
bright failure
defective dot brighter than the specified display luminance
2.5.11
bright spot
local area brighter than the specified display luminance
2.5.12
close dot failure
dot failures within a specified distance of each other
2.5.13
colour non-uniformity
phenomenon in which chromaticity differs from one part of a screen to another
Note 1 to entry: Colour non-uniformity refers in particular to differences in chromaticity.
2.5.14
contrast ratio
ratio of white luminance to black luminance of the image, including light reflected from the
display
Note 1 to entry: This ratio is strongly dependent on the ambient light.
2.5.15
cross-talk
unwanted luminance on a part of a display area produced by an image displayed on another
part of the display
2.5.16
current modulation
method for variation of the intensity of emission in organic light emitting diode displays by
variation of the amplitude of the driving current

2.5.17
dark defect
defective dot darker than the specified display luminance or non-emissive
2.5.18
dark spot
local non-emissive area in an emissive area
2.5.19
delay time
time interval from switching the display from the OFF state to the ON state or from the ON
state to the OFF state till the instant at which luminance changes by 10 % of the difference in
the ON and OFF luminance levels
2.5.20
diagonal size
length of display diagonal
2.5.21
dot
each individually addressable element of a display
Note 1 to entry: In a colour display a dot is equal to a subpixel, in a monochromatic display a dot is equal to a
pixel.
2.5.22
duty ratio
fraction of pixel ON time while the scan signal is selected in one frame in a multiplex driving
scheme, such as in a passive matrix display
2.5.23
flexibility
mechanical pliancy of a panel to an external mechanical or thermal stress
2.5.24
flicker
impression of unsteadiness of the visual sensation induced by a light stimulus whose
luminance or spectral distribution fluctuates with time
2.5.25
frame frequency
number of image frames per second
2.5.26
frame rate control
method for realizing grey scale that makes use of the temporal integration of the human visual
system
Note 1 to entry: Different optical levels in different frames will be averaged over time to provide the sensation of a
certain grey scale.
2.5.27
grey scale
range of luminance levels between maximum luminance and minimum luminance
2.5.28
grey shade
displayed shade of grey corresponding to a given command level or drive level

– 18 – IEC 62341-1-2:2014  IEC 2014
2.5.29
half luminance lifetime
time period before the luminance decreases to 50 % of the initial luminance in operation
2.5.30
image sticking
image persistence
persistent remnant of an image on the screen after a new image is presented.
Note 1 to entry: The image sticking does not disappear in a short time.
2.5.31
initial luminance
luminance after factory ageing
2.5.32
line failure
display defect whereby many pixels or subpixels failures occur along a line
2.5.33
line-at-a-time scanning
scanning system that selects scan lines sequentially and
synchronously inputs a signal to the signal electrode
2.5.34
linked dot failure
sequence of connected dot failures
2.5.35
logic voltage
voltage applied to operate the logic circuitry in an organic light emitting diode display module
2.5.36
luminance lifetime
elapsed time required for the luminance to decrease to a specified fraction of the initial
luminance in operation
Note 1 to entry: Initial luminance is defined as the luminance after factory ageing.
2.5.37
luminance uniformity
uniformity of luminance produced by different areas of the organic light emitting diode display
2.5.38
luminous current efficiency
luminance divided by the applied current per unit area
Note 1 to entry: Expressed in cd/A.
2.5.39
luminous efficacy
total luminous flux from the display divided by the applied electric power
Note 1 to entry: Expressed in lm/W, often misapplied to luminous power efficiency.
2.5.40
maximum luminance
maximum value of luminance that can be displayed

2.5.41
mura
region(s) of luminance non-uniformity and colour non-uniformity that generally vary more
gradually than subpixel defects
Note 1 to entry: For classification, the maximum dimension should be less than one fourth of the display width or
height.
2.5.42
operating lifetime
time period during which a device meets its specifications under nominal operating conditions
2.5.43
out-coupling efficiency
ratio of the luminous flux out of a panel to the luminous flux emitted in a light emitting layer
2.5.44
pinhole
small defect in the electroluminescence film, electrode film, protective film, etc.
2.5.45
pixel
minimum display unit that can perform full display functions
Note 1 to entry: For example, in a colour display based on RGB vertical stripes, three consecutive RGB elements
constitute one pixel.
2.5.46
pixel pitch
distance between corresponding points on adjacent pixels, both horizontally and vertically
SEE: Figure A.1
2.5.47
point-at-a-time scanning
scanning method that selects a pixel or a subpixel at a time
sequentially
2.5.48
power consumption
electric power that an organic light emitting diode display consumes while operated
2.5.49
precharge
operation to charge the organic light emitting diode before emission
2.5.50
pulse width modulation
method of grey scale modulation using constant pulse amplitude while varying the pulse width
according to the level of the input signal
2.5.51
recombination efficiency
ratio of recombination of injected electrons and holes in a light emitting layer
2.5.52
resolution
ability of the display to reproduce objects that are close together and which remain
distinguishable
– 20 – IEC 62341-1-2:2014  IEC 2014
Note 1 to entry: Often confused with addressability.
2.5.53
response time
time that is required from the change of an electrical input signal to the corresponding change
of the optical response of the display
2.5.54
scratch defect
defect caused by scratching of the glass or polarizer surface
2.5.55
specular reflectance
ratio of the regularly reflected part of the (whole) reflected flux, to the incident flux
2.5.56
stain
display defect having an area larger than a pixel and unclear boundaries
2.5.57
subframe modulation
method for generating grey scale, that uses multiple subframes with different periods
Note 1 to entry: Specifically, a drive system in which one frame consists of multiple subframes having different
periods that are turned ON and OFF to reproduce a grey scale.
2.5.58
subpixel
each individually addressable element of a matrix display, which makes up one pixel
Note 1 to entry: For example, each R, G, or B element in a colour display based on RGB is a subpixel.
2.5.59
subpixel arrangement
arrangement of subpixels making up a pixel, e.g. stripe or delta-arrangements
Note 1 to entry: ”RGB” is an example of primaries. There are pixels with other subpixels, for example RGBW or
RGBC.
2.5.60
supply current
current provided by a power supply for normal operation of an organic light emitting diode
display module
2.5.61
viewing angle range
range of viewing angle over which the visual specification is satisfied
2.5.62
viewing area
active area plus any contiguous areas that display permanent visual information or a display
background
2.5.63
viewing direction
viewing angle
direction or angle for viewing an organic light emitting diode display which is defined by the
inclination angle θ and the azimuth φ
SEE: Figure A.2.
2.5.64
visible failure
generic term of failure characterized by a difficulty to view the content of an effective display
area
Note 1 to entry: Dot failures, line failures, and stains are some examples.
2.5.65
voltage modulation
method of grey scale display technology, that varies the voltage according to a grey scale of
an input signal without varying the pulse width
2.6 Terms related to the production process
2.6.1
ageing
manufacturing process consisting of opera
...