IEC 62908-12-10:2025

Touch and interactive displays - Part 12-10: Measurement methods of touch displays - Touch and electrical performance

IEC 62908-12-10:2025 specifies the standard measuring conditions and measurement methods for determining touch and hovering performance of a touch sensor module. This document is applicable to touch sensor modules, whereas the structural relationship between touch sensor, touch controller, touch sensor module, display panel, touch display panel, and touch display module is defined in IEC 62908-1-2. This third edition cancels and replaces the second edition published in 2023. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous edition:
a) added principle of force sensitive touch sensor module and force-output characteristics measurement;
b) added required equipment for force-output characteristic measurement of force sensitive touch sensor module;
c) added test method for force-output characteristics measurement.

General Information

• Status: Published
• Publication Date: 17-Dec-2025
• ICS: 31.120 - Electronic display devices
• Technical Committee: TC 110 - Electronic displays
• Drafting Committee: WG 9 - TC 110/WG 9
• Current Stage: PPUB - Publication issued
• Start Date: 18-Dec-2025
• Completion Date: 21-Jan-2026

Relations

• Revises: IEC 62908-12-10:2023 - Touch and interactive displays - Part 12-10: Measurement methods of touch displays - Touch and electrical performance
• Effective Date: 23-Feb-2024

Overview

IEC 62908-12-10:2025 - "Touch and interactive displays − Part 12‑10: Measurement methods of touch displays − Touch and electrical performance" is the third edition of an IEC standard that defines standard measuring conditions and methods for evaluating touch and hovering performance of touch sensor modules. It replaces the 2023 edition and adds measurement principles, required equipment, and test methods for force sensitive touch sensor modules and their force‑output characteristics. The standard applies where the device composition (touch sensor, controller, module, panel and display module) is defined (see IEC 62908‑1‑2).

Key topics and technical requirements

The standard specifies test setups, procedures and reporting requirements for a wide range of touch and electrical performance metrics, including:

• Standard measuring environment and atmospheric conditions, positioning equipment and human‑operator alternatives
• Test tools: test bars, touch pens and added force sensors for force‑sensitive modules
• Touch performance tests: accuracy, repeatability/jitter, linearity, reproducibility
• Signal integrity and timing: signal‑to‑noise ratio (SNR), report rate, latency
• Immunity and robustness: electrical noise immunity, optical noise immunity, water droplet immunity
• Power and hover characteristics: power consumption, perpendicular hover distance, in‑plane hovering performance
• New in this edition: force‑output characteristics test method, including required equipment and reporting
• Annex A: electrical performance measurement methods (resistance and trans‑capacitance) for touch sensors

The document defines test grids, edge/centre areas, measurement definitions and required reports - ensuring repeatable, comparable results across laboratories and suppliers.

Applications and who uses it

IEC 62908‑12‑10:2025 is intended for:

• Touch display manufacturers and touch sensor module OEMs for design verification and supplier QA
• Product engineers and R&D teams validating touch responsiveness, hover and force sensing capabilities
• Test and certification laboratories performing standardized measurements for compliance and benchmarking
• Procurement and quality assurance professionals creating test specifications and acceptance criteria
• Systems integrators and OEMs assessing touch performance for handhelds, tablets, automotive displays, kiosks and industrial HMIs

Benefits include consistent measurement procedures, objective performance comparisons, improved interoperability, and clearer criteria for specification and acceptance testing.

Related standards

• IEC 62908‑1‑2 - defines structural relationships between touch sensor, controller, modules and display assemblies (referenced for scope and definitions).

Standards Content (Sample)

IEC 62908-12-10 ®
Edition 3.0 2025-12
INTERNATIONAL
STANDARD
REDLINE VERSION
Touch and interactive displays -
Part 12-10: Measurement methods of touch displays - Touch and electrical
performance
ICS 31.120 ISBN 978-2-8327-0970-2

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CONTENTS
FOREWORD. 5
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 7
4 Measuring conditions . 7
4.1 Standard measuring environmental conditions . 7
4.2 Standard atmospheric conditions for reference measurements and tests . 7
4.3 Standard positioning equipment and setup . 8
4.4 Human operator alternative to standard positioning equipment . 9
4.5 Test bar and touch pen . 10
4.6 Equipment for measurement of force-output characteristics . 11
5 Touch performance measurement methods . 12
5.1 General . 12
5.2 Accuracy test . 12
5.2.1 Purpose . 12
5.2.2 Test procedure . 13
5.2.3 Report . 17
5.3 Repeatability or jitter test . 17
5.3.1 Purpose . 17
5.3.2 Test procedure . 18
5.3.3 Report . 20
5.4 Linearity test . 20
5.4.1 Purpose . 20
5.4.2 Test procedure . 20
5.4.3 Report . 23
5.5 Reproducibility test . 23
5.5.1 Purpose . 23
5.5.2 Test procedure . 24
5.5.3 Report . 25
5.6 Signal-to-noise ratio (SNR) test . 26
5.6.1 Purpose . 26
5.6.2 Test procedure . 27
5.6.3 Report . 28
5.7 Report rate test . 28
5.7.1 Purpose . 28
5.7.2 Test procedure . 28
5.7.3 Report . 29
5.8 Latency test . 29
5.8.1 Purpose . 29
5.8.2 Test procedure . 29
5.8.3 Report . 30
5.9 Electrical noise immunity test . 30
5.9.1 Purpose . 30
5.9.2 Test procedure . 30
5.9.3 Report . 31
5.10 Water droplet immunity test . 31
5.10.1 Purpose . 31
5.10.2 Test procedure . 32
5.10.3 Report . 32
5.11 Optical noise immunity test . 32
5.11.1 Purpose . 32
5.11.2 Test procedure . 33
5.11.3 Report . 33
5.12 Power consumption test . 33
5.12.1 Purpose . 33
5.12.2 Test procedure . 33
5.12.3 Report . 33
5.13 Perpendicular hover distance test . 33
5.13.1 Purpose . 33
5.13.2 Test procedure . 33
5.13.3 Report . 34
5.14 Force-output characteristics test . 34
5.14.1 Purpose . 34
5.14.2 Test procedure . 34
5.14.3 Report . 35
6 In-plane hovering performance measurement methods . 35
6.1 General . 35
6.2 Accuracy test . 35
6.2.1 Purpose . 35
6.2.2 Test procedure . 36
6.2.3 Report . 38
6.3 Repeatability or jitter test . 39
6.3.1 Purpose . 39
6.3.2 Test procedure . 39
6.3.3 Report . 41
6.4 Report rate test . 42
6.4.1 Purpose . 42
6.4.2 Test procedure . 42
6.4.3 Report . 43
Annex A (informative) Electrical performance measurement methods of touch sensors . 44
A.1 Resistance . 44
A.1.1 General . 44
A.1.2 Test samples . 44
A.1.3 Measurement equipment . 44
A.1.4 Procedures . 44
A.1.5 Data analysis . 45
A.1.6 Report . 45
A.2 Trans-capacitance . 45
A.2.1 General . 45
A.2.2 Test samples . 45
A.2.3 Measurement equipment . 45
A.2.4 Procedure . 45
A.2.5 Data analysis . 46
A.2.6 Report . 46
Bibliography . 47

Figure 1 – Composition of test equipment . 8
Figure 2 – Concept of performance measurement . 9
Figure 3 – Example of manual test tool (left), positioning without triggering a touch
event (middle) and recording a touch event (right) . 9
Figure 4 – Examples of test bars . 11
Figure 5 – Force sensor added to Figure 1 (in red) for measurement of force-output
characteristics of a force sensitive touch sensor module . 12
Figure 6 – Block diagram showing functions and data added to Figure 2 (in red) for
force-output characteristics measurement . 12
Figure 7 – Location of edge area and centre area . 13
Figure 8 – Point grid . 14
Figure 9 – Accuracy definition . 14
Figure 10 – Example of measurement result and calculation of accuracy . 17
Figure 11 – Repeatability in the touch sensor module . 18
Figure 12 – Example of measurement result for repeatability . 20
Figure 13 – Dragging line for linearity test . 21
Figure 14 – Linearity definition . 21
Figure 15 – Example of measurement and calculation of linearity . 23
Figure 16 – Example of reproducibility test results . 24
Figure 17 – Reproducibility test procedure . 25
Figure 18 – Examples of measurements of reproducibility – Velocity dependence . 26
Figure 19 – SNR definition concept . 27
Figure 20 – Dragging direction for reporting time measurement . 28
Figure 21 – Reporting time interval measurement . 29
Figure 22 – Latency measurement . 29
Figure 23 – Example of the effect of external noise . 30
Figure 24 – External noise injection . 31
Figure 25 – Report of external noise immunity . 31
Figure 26 – Example of water drop effect . 32
Figure 27 – Water droplet test procedure . 32
Figure 28 – Perpendicular hover distance measurement . 34
Figure 29 – Examples of force-output characteristics . 34
Figure 30 – Point grid . 36
Figure 31 – Accuracy definition for in-plane of XY coordinates on the target projection
plane (l) of the active area . 37
Figure 32 – Accuracy definition for Z coordinate on the target projection plane (l) of the
active area . 37
Figure 33 – Repeatability for in-plane of XY coordinates on the target projection plane
(l) of the active area . 39
Figure 34 – Repeatability for Z coordinate on the target projection plane (l) of the
active area . 40
Figure 35 – Dragging direction of in-plane for reporting time measurement . 42
Figure 36 – Dragging direction of Z-axis for reporting time measurement . 43
Figure 37 – Reporting time interval measurement . 43
Figure A.1 – Diagrammatic representation of measurement of resistance . 45
Figure A.2 – Diagrammatic representation of measurement of capacitance . 46

Table 1 – Standard conditions for reference measurements and tests . 8
Table A.1 – Specification of LCR impedance meter . 44

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
Touch and interactive displays -
Part 12-10: Measurement methods of touch displays -
Touch and electrical performance

FOREWORD
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
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This redline version of the official IEC Standard allows the user to identify the changes made
to the previous edition IEC 62908-12-10:2023. A vertical bar appears in the margin wherever a
change has been made. Additions are in green text, deletions are in strikethrough red text.

IEC 62908-12-10 has been prepared by IEC technical committee 110: Electronic displays. It is
an International Standard.
This third edition cancels and replaces the second edition published in 2023. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) added principle of force sensitive touch sensor module and force-output characteristics
measurement;
b) added required equipment for force-output characteristic measurement of force sensitive
touch sensor module;
c) added test method for force-output characteristics measurement.
The text of this International Standard is based on the following documents:
Draft Report on voting
110/1757/CDV 110/1794A/RVC
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 International Standard is English.
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/publications.
A list of all parts in the IEC 62908 series, published under the general title Touch and interactive
displays, 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 webstore.iec.ch in the data related to the
specific document. At this date, the document will be
– reconfirmed,
– withdrawn, or
– revised.
1 Scope
This part of IEC 62908 specifies the standard measuring conditions and measurement methods
for determining touch and hovering performance of a touch sensor module. This document is
applicable to touch sensor modules, where whereas the structural relationship between touch
sensor, touch controller, touch sensor module, display panel, touch display panel, and touch
display module is defined in IEC 62908-1-2.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies.
For undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 60068-1, Environmental testing - Part 1: General and guidance
IEC 62908-1-2, Touch and interactive displays - Part 1-2: Generic - Terminology and letter
symbols
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60068-1 and
IEC 62908-1-2 apply.
ISO and IEC maintain terminology databases for use in standardization at the following
addresses:
– IEC Electropedia: available at https://www.electropedia.org/
– ISO Online browsing platform: available at https://www.iso.org/obp
4 Measuring conditions
4.1 Standard measuring environmental conditions
Measurements shall be carried out under the standard environmental conditions:
– temperature: 25 °C ± 3 °C,
– relative humidity: 25 % RH to 85 % RH,
– atmospheric pressure: 86 kPa to 106 kPa.
When different environmental conditions are used, they shall be noted in the measurement
report.
4.2 Standard atmospheric conditions for reference measurements and tests
If the parameters to be measured depend on temperature, pressure and humidity, and their
dependence on temperature, pressure and humidity is unknown, the atmospheres to be
specified shall be selected from the values shown in Table 1. The selected values shall be
noted in the relevant specifications.
Table 1 – Standard conditions for reference measurements and tests
a a, b a
Temperature Relative humidity Air pressure
°C % RH kPa
(20, 25, 30, and 35) ± 3 45 to 75 86 to 106
a
Including extreme values.
b 3
Absolute humidity ≤ 22 g/m .
4.3 Standard positioning equipment and setup
The standard positioning equipment for touch performance shall be the positioning machine
equipped with a test bar, a moving arm, and a stage onto which the touch sensor module is
placed, as shown in Figure 1. The positioning machine shall move its arm and stage to place
the test bar on or over the touch sensor module.
There are three types of positions associated with a given test: target, actual and reported
positions. The target position is a desired measurement location in physical space referenced
to a fixed datum on or over the touch sensor module surface. The actual position is the actual
location of contact or hovering during test, referenced to the same fixed datum, which can differ
from the target position due to test bar placement error. The reported position is the location
reported by the touch controller.
As shown in Figure 2, the reported positions from the touch controller are analysed to define
performance measures with respect to the target positions.
The touch sensor module and the stage shall be aligned correctly while setting up the
measurement equipment, because a misalignment between them can introduce coordinate
shifts or rotation between the actual touch positions and target positions; each positioning
machine has its inherent accuracy, which means that an actual touched position does not
coincide with its target position. The performance measurements based on the target positions
can include errors due to the accuracy of the positioning machine. The touch sensor module
under test shall be attached to the stage and connected to the electrical interface. The test bar
of the selected diameter shall be attached to the moving arm. In case of measurement of the
pen touch performance, instead of the test bar, a selected touch pen (stylus pen) shall be
attached to the moving arm.
Figure 1 – Composition of test equipment
Figure 2 – Concept of performance measurement
4.4 Human operator alternative to standard positioning equipment
Under certain circumstances, for example if the display under test is too large for suitable
positioning equipment to be available, a suitably designed test arm may be manually positioned
to enable completion of a subset of the tests described in this document. In this situation, it is
important to design the test arm needs to be designed carefully to minimise the reasonable
achievable error between actual and target positions when conducting measurements. An
example of such a test arm can consist of a rod with a sliding tip (Figure 3, left), whose materials
are chosen so that contact between the rod and the display does not trigger a touch event
(Figure 3, middle), whereas contact between the sliding tip and the display does trigger a touch
event (Figure 3, right). Such a test arm can be placed accurately and reliably by the human
operator with the sliding tip away from the display, subsequent to which a measurement can be
made by sliding the tip into contact with the display.
The human operator alternative is not recommended for hovering performance measurements
because it is difficult to ensure the accuracy of positions, including the height.

Figure 3 – Example of manual test tool (left), positioning without triggering
a touch event (middle) and recording a touch event (right)
4.5 Test bar and touch pen
The parameters of the test bar shall be size, shape, and material. Examples of suitable sizes
and shapes of the test bar are shown in Figure 4. The material of the test bars should be brass
or conductive polyamide resin. The electrical resistivity of the test bars should be greater than
2 4
10 Ω cm and less than 10 Ω cm, and the hardness should be greater than R119. The material
parameters for the test bar shall be appropriately chosen given the device category under test.
When the touch sensor module is a capacitive touch system, the test bar shall be electrically
conductive and shall additionally be grounded in order to avoid potential performance
degradation due to electrical noise, unless otherwise stated. A test bar may have an insulating
layer on the base to model the effect of a gloved finger.
For reflection-based optical systems, the reflectivity of the contact end of the test bar shall be
chosen to be spectrally representative of human skin.
In all cases, the appropriate properties (including size, shape and material) of the test bar shall
be reported.
In case of measurement of the pen touch performance, the selected touch pen shall be applied
instead of the test bar. The touch pen corresponding to the touch sensor module shall be
selected, because there are several types of touch pens (see IEC TR 62908-1-3). The
information of the selected touch pen and related properties (i.e. tilt angle of touch pen,
pressure of touch pen, etc.) shall be reported.

NOTE ø (test bar diameter) = 4 1,6 mm, 6 4 mm, 7 6 mm, 9 8 mm, or 12 10 mm.
Figure 4 – Examples of test bars
4.6 Equipment for measurement of force-output characteristics
To measure the force-output characteristics of a force sensitive touch sensor modules, the
positioning machine shall be equipped with a force sensor as shown in Figure 5 to detect
physical force applied to the touch sensor module by measuring normal force from the touch
sensor module. The resolution of the force sensor shall be smaller than 0,01 N or 1 gf
(see ISO 7500-1).
The positioning machine shall move its moving arm in the direction vertically to the touch sensor
module to vary the force applied to the touch sensor module. Then the physical force indicated
by the force sensor and the force-output level, which is an output digital value from the touch
sensor module, are used for the force-output characteristics test (see Figure 6).
NOTE According to the industry terminology, "force-output level" is also known as "pressure" or "pressure level".
Figure 5 – Force sensor added to Figure 1 (in red) for measurement of force-output
characteristics of a force sensitive touch sensor module

Figure 6 – Block diagram showing functions and data added to Figure 2 (in red)
for force-output characteristics measurement
5 Touch performance measurement methods
5.1 General
Fundamental touch performance measurement methods are described in Clause 5. They shall
be applied during the characterization of a touch sensor module to provide a good user
experience (see Annex A regarding electrical performance measurement methods of touch
sensors.)
5.2 Accuracy test
5.2.1 Purpose
The purpose of this test is to measure the ability of touch sensors and modules to indicate how
close touch positions are reported relative to their target positions.
5.2.2 Test procedure
5.2.2.1 General
For the accuracy measurement, one of the following two methods can be selected. The first
method is a straightforward method to evaluate the distance between each target point and its
corresponding reported point. The second method is an indirect method where target grid points
are estimated from reported points. This method can tolerate coordinate shifts which are caused
by a misalignment between the touch sensor module and the stage while setting up the
measurement equipment.
5.2.2.2 Method 1
The active area is defined as the area where touch is recognized. The centre area is defined
as the rest of the active area without the edge area as shown in Figure 7. The edge area is
defined as an area corresponding to the width (W) of the edge of the active area. The origin
and axis direction shall be defined.
The touch sensor module under test shall be attached to the stage and connected to the
electrical interface. The test bar of the selected diameter size, shape and material shall be
attached to the moving arm. For a precise measurement of the accuracy, the test equipment
should be set up properly. The measurement points in the test grid are evenly spaced along
both X and Y axes, away from the origin and spanning the whole active area of the touch sensor
panel as shown in Figure 8.
Figure 7 – Location of edge area and centre area
NOTE m, n correspond to the number of points in the X and Y directions.
Figure 8 – Point grid
At each target grid point (i, j), lift the test bar down and up, and collect the touch reports p times.
As shown in Figure 9, the accuracy is defined as the distance between the target coordinate
and the mean reported coordinate.

Figure 9 – Accuracy definition
In the centre area, calculate the accuracy, that is, the maximum of accuracy, the standard
deviation of accuracy and the average of accuracy, as shown in Formula (1) to Formula (5). In
the edge area, the accuracy is calculated in the same manner.
AA= max( )
ccmax cci, j (1)
nm
()AA−
∑∑ ccij, ccmean
ji11
(2)
A =
ccσ
q
nm
()A
∑∑
ccij,
ji11
(3)
A =
ccmean
q
A (xr− xt )(+ yr− yt )
(4)
ccij, ij, ij, ij,
ij,
pp
xr yr
∑ ∑
ij, ,k ij, ,k
k 11k
(5)
xr , yr
ij,
ij,
pp
where
p is the number of reports at a target point (1,2,…);
q is the number of measurement points (m × n);
th
i, j, k is the k data in number of reports (p) at a target point (i, j);
A is the distance between the target coordinate and the mean reported coordinate;
cci,j
A is the maximum of accuracy;
ccmax
A is the standard deviation of accuracy;
ccσ
A is the average of accuracy.
ccmean
In case of measurement of the pen touch performance instead of the test bar, the selected
touch pen shall be applied.
5.2.2.3 Method 2
The test bar shall be placed at m × n target grid points equally spaced by a distance d in both
horizontal and vertical directions. When the touch sensor module is a capacitive touch system,
d shall be smaller than or equal to one fourth of the sensor channel pitch, and m × d and n × d
are greater than or equal to the sensor channel pitch. At each target grid point (i, j), collect the
touch reports 50 times to 100 times in one of the following two ways:
a) lift the test bar down and up for each report at each target, or
b) keep the test bar stationary at each target.
The data from a) and b) is used in the calculation of repeatability.
Calculate the mean point of the reported points at (i, j).
xy
,
( )
ij,
ij,
Then find the best fitted grid
==
==
=
==
==
X ,Y = i−+1 dx ,1j−+d y
( ) ( ) (6)
( ) ( )
ij, ij, best best
where i = 1,…,m and j = 1,…,n.
This minimizes the mean square distance
{(X − x ) +−(Yy ) }
∑
i, j i, j i, j
i, j
(7)
i=1,2,.,m,
jn=1,2,.,
from
xy,
(8)
( )
i, j ij,
where i = 1,…,m and j = 1,…,n.
The shifts (x y ) for the best grid are obtained by equating the derivatives of the distance
best, best
by x and y to zero, and are calculated as
best best
 
xy
∑∑
i, j
i, j
 
i 1,2,.,m, i 1,2,.,m,
 
n−−11d md
( ) ( )
jn1,2,., jn1,2,.,
( xy,,)=−−
  (9)
best best
mn 22mn
 
 
 
 
The accuracy at (i, j) is defined as the distance between the grid point (X ,Y ) and the mean
i,j i,j
point xy .
,
( )
ij,
ij,
(10)
A X− x +−Yy
( ) ( )
cci, j i, j i, j ij,
i, j
An example of a measurement result and the corresponding calculation of accuracy is shown
in Figure 10.
In case of measurement of the pen touch performance, instead of the test bar, the selected
touch pen shall be applied.
=
==
==
Figure 10 – Example of measurement result and calculation of accuracy
5.2.3 Report
The following items shall be reported:
– selected measurement method;
– selected size, shape and material of the test bar or the selected touch pen and properties
(tilt angle of touch pen and pressure of touch pen);
– width of edge area W;
– target position;
– number of measurements at each point;
– maximum of accuracy for all points in each area;
– average of accuracy for all points in each area;
– standard deviation of accuracy for all points in each area.
5.3 Repeatability or jitter test
5.3.1 Purpose
The purpose of this test is to measure the ability of touch sensors and modules to indicate how
precisely touch positions are reported, given a sequence of touches in the same target position,
where "precise" means that the reported positions are "close to each other".
5.3.2 Test procedure
5.3.2.1 General
For the repeatability or jitter measurement, one of the following two methods can be selected,
as in the case of accuracy measurement.
The repeatability is defined with the same reported data collected for accuracy measurement
at target grid point (i, j) by lifting the test bar down and up for each report. The jitter is defined
with the reported data collected by keeping the test bar stationary at target grid point (i, j). The
repeatability measurement is applicable to the jitter measurement.
5.3.2.2 Method 1
The touch sensor module under test shall be attached to the stage and connected to the
electrical interface. The test bar of the selected diameter shall be attached to the moving arm.
At each target grid point (i, j), lift the test bar down and up, and collect the touch reports p times,
As shown in Figure 11, the repeatability is defined as the distance between the reported
coordinate and the mean reported coordinate.
Repeatability/Jitter is standard
Target coordinate
R
(xt,yt) ti,j
i,j
Mean reported coordinate
(xr,yr)
i,j
Reported coordinate
(xr,yr)
i,j
IEC
Figure 11 – Repeatability in the touch sensor module
In the centre area, calculate the repeatability, that is, the maximum, standard deviation and the
average, as shown in Formula (11) to Formula (15). In the edge area, the repeatability is
calculated in the same manner.
RR= max( )
tmax ti, j (11)
nm
()RR−
∑∑ ti, j tmean
ji11
(12)
R =
tσ
q
nm
()R
∑∑
ti, j
ji11
(13)
R =
tmean
q
==
==
R (xr− xr )(+ yr− yr ) (14)
i, j
ti, j i, j i, j i, j
p p
xr yr
∑∑
i, j,k i, j,k
kk1 1
(15)
xr , yr
i, j
i, j
pp
where
p is the number of reports at a target point (1,2,…);
q is the number of measurement points = m × n;
th
i, j, k is the k data in number of reports (p) at a target point (i, j);
R is the distance between the target coordinate and the mean reported coordinate;
ti,j
R is the maximum of repeatability;
tmax
R is the standard deviation of repeatability;
tσ
R is the average of repeatability.
tmean
In case of measurement of the pen touch performance instead of the test bar, the selected
touch pen shall be applied.
5.3.2.3 Method 2
The repeatability is defined with the same reported data collected for the accuracy
measurement at target grid point (i, j) by lifting the test bar down and up for each report.
as the root mean square distance between the reported
Calculate the standard deviation σ
i, j
points at target grid point (i, j) and their mean point xy .
,
( )
ij,
ij,
The repeatability is defined as
R = max σ
( )
t i, j (16)
ij,
An example of a measurement result for repeatability is shown in Figure 12.
In case of measurement of the pen touch performance instead of the test bar, the selected
touch pen shall be applied.
==
==
=
Figure 12 – Example o
...