ISO/IEC 15423-1:2001

INTERNATIONAL ISO/IEC
STANDARD 15423-1
First edition
2001-02-15
Information technology — Automatic
identification and data capture
techniques — Bar code scanner and
decoder performance testing —
Part 1:
Linear symbols
Technologies de l'information — Techniques d'identification automatique et
de capture des données — Contrôle de scanner de code à barres et de
performance du décodeur —
Partie 1: Symboles linéaires
Reference number
©
ISO/IEC 2001
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ii © ISO/IEC 2001 – All rights reserved

Contents
1 Scope. 1
2 Normative references . 1
3 Terms and definitions. 2
4 Symbols and abbreviated terms . 6
5 Categories of scanning equipment . 6
5.1 Scanners with single axis reading diagram . 6
5.2 Scanners with two axis reading diagram . 6
5.3 Scanners with three axis reading diagram. 6
6 Test requirements . 7
6.1 Test methods. 7
6.2 Selection of equipment for testing . 7
6.3 Test conditions. 7
6.3.1 Environment. 7
6.3.2 Equipment configuration . 7
6.4 Test Charts . 7
6.5 Test equipment.11
6.5.1 Test equipment for scanners with single axis reading diagram .11
6.5.2 Test equipment for scanners with two axis reading diagram .11
6.5.3 Test equipment for scanners with three axis reading diagram.11
6.5.4 Additional test equipment.11
6.5.5 Test equipment for complete reading systems.11
6.6 Test criteria.12
6.6.1 Test criterion for complete reading systems and decoders.12
6.6.2 Test criterion for scanners.12
6.7 Parameters to be tested and test methods .12
6.7.1 Scanners with single axis reading diagram .13
6.7.2 Scanners with two axis reading diagram .15
6.7.3 Scanners with three axis reading diagram.18
6.7.4 Decoder .19
6.7.5 Complete Reading Systems.20
6.8 Test report .21
7 Certification and labelling.21
8 Equipment specification .21
8.1 General .21
8.2 Scanner/decoder interface.22
8.3 Human interface .23
8.4 Computer interface.23
8.5 Digital input and output (I/O) .23
8.6 Programming and configuration .23
Annex A (normative) General operational requirements.24
A.1 Installation, operation and maintenance - general.24
A.2 Power supply.24
A.3 Temperature .24
A.3.1 Operating temperature range.24
© ISO/IEC 2001 – All rights reserved iii

A.3.2 Storage temperature range . 24
A.4 Humidity. 24
Annex B Classification of scanners. 25
B.1 Types of scanner. 25
B.1.1 Scanners with single axis reading diagram . 25
B.1.2 Scanners with two axis reading diagram . 26
B.1.3 Scanners with three axis reading diagram. 27
B.2 Additional methods of categorisation . 29
Annex C Example of decodability calculation. 30
Bibliography . 32
iv © ISO/IEC 2001 – All rights reserved
(informative)
(informative)
Foreword
ISO (the International Organization for Standardization) and IEC (the International Electrotechnical Commission)
form the specialized system for worldwide standardization. National bodies that are members of ISO or IEC
participate in the development of International Standards through technical committees established by the
respective organization to deal with particular fields of technical activity. ISO and IEC technical committees
collaborate in fields of mutual interest. Other international organizations, governmental and non-governmental, in
liaison with ISO and IEC, also take part in the work.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 3.
In the field of information technology, ISO and IEC have established a joint technical committee, ISO/IEC JTC 1.
Draft International Standards adopted by the joint technical committee are circulated to national bodies for voting.
Publication as an International Standard requires approval by at least 75 % of the national bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this part of ISO/IEC 15423 may be the subject of
patent rights. ISO and IEC shall not be held responsible for identifying any or all such patent rights.
International Standard ISO/IEC 15423-1 was prepared by Joint Technical Committee ISO/IEC JTC 1, Information
technology, Subcommittee SC 31, Automatic identification and data capture techniques.
ISO/IEC 15423 consists of the following parts, under the general title Information technology — Automatic
identification and data capture techniques — Bar code scanner and decoder performance testing:
� Part 1: Linear symbols
� Part 2: Two-dimensional symbols
Annex A forms a normative part of this part of ISO/IEC 15423. Annexes B and C are for information only.
© ISO/IEC 2001 – All rights reserved v

Introduction
The technology of bar coding is based on the recognition of patterns encoded in bars and spaces of defined
dimensions according to rules defining the translation of characters into such patterns, known as the symbology
Bar code symbols can be produced with a wide variety of printing and other techniques, and the overall symbol
There is a wide range of bar code reading equipment using various scanning techniques, which enable bar code
Bar code symbols may be a) "linear" i.e. read in a single dimension, where the height of the bars provides
redundancy of information, or b) "two dimensional", either in stacked rows to be read unidimensionally in sequence,
Manufacturers of bar code equipment, the producers of bar code symbols and the users of bar code technology,
require publicly available standard test specifications for bar code reading equipment to ensure the accuracy and
vi © ISO/IEC 2001 – All rights reserved
consistency of performance of this equipment.
into a form meaningful to the host computer system or otherwise to the user.
Bar code reading equipment must be capable of reliably converting the information represented as a bar code symbol
or as a matrix of elements requiring two dimensional reading.
symbols to be read under many different conditions.
dimensions can be uniformly scaled to suit particular requirements.
specification.
INTERNATIONAL STANDARD ISO/IEC 15423-1:2001(E)
Information technology — Automatic identification and data capture
techniques — Bar code scanner and decoder performance
testing — Part 1: Linear symbols
1 Scope
bar code scanning and decoding equipment. It defines requirements in respect of techniques for the scanning and
decoding of linear symbols. It deals with bar code scanning and decoding equipment both as integrated reading
systems and as discrete units. It defines performance of the equipment in a particular configuration (e.g. a specific
model) irrespective of the individual components used. It also defines in a normative annex a means of classifying
Part 2 of ISO/IEC 15423 covers the requirements for the performance testing of equipment for the scanning and
2 Normative references
this part of ISO/IEC 15423. For dated references, subsequent amendments to, or revisions of, any of these
publications do not apply. However, parties to agreements based on this part of ISO/IEC 15423 are encouraged to
investigate the possibility of applying the most recent editions of the normative documents indicated below. For
undated references, the latest edition of the normative document referred to applies. Members of ISO and IEC
Information technology — Automatic identification and data capture techniques — Bar code symbol
print quality test specification.
15417, Information technology — Automatic identification and data capture techniques — Bar code sym-
bology specification — Code 128.
15424, Information technology — Automatic identification and data capture techniques — Data Carrier
Identifiers (including Symbology Identifiers).
, Information technology — Automatic identification and data capture techniques — Bar code veri-
fier conformance specification — Part 1: Linear symbols.
16388, Information technology — Automatic identification and data capture techniques — Bar code sym-
bology specification — Code 39.
Bar coding — Terminology.
© ISO/IEC 2001 – All rights reserved 1
1556, EN
ISO/IEC
15426-1 ISO/IEC
ISO/IEC
ISO/IEC
15416, ISO/IEC
maintain registers of currently valid International Standards.
The following normative documents contain provisions which, through reference in this text, constitute provisions of
decoding of two-dimensional symbols.
NOTE
scanners and operational parameters.
This part of ISO/IEC 15423 defines the test equipment and procedures to be used to determine the performance of

3 Terms and definitions
3.1
contact scanner
A particular type of scanner in which the scanning action takes place with the scanner in actual or near contact with
,e
3.2
decode redundancy
The acquisition of a predetermined number of identical decodes before acceptance by a decoder of a valid decode.
3.3
exit window
The datum point from which the reading diagram is measured, lying in the plane normal to the beam midpoint closest
3.4
maximum reading distance
3.5
minimum reading distance
3.6
raster
3.7
raster distance
The distance between the two most widely spaced adjacent scan lines projected on a plane at a defined distance
3.8
raster width
The distance between the two outermost scan lines projected on a plane at a defined distance from the scanner exit
window. This covers a reading field which depends on the construction of the scanner and on the reading distance.
3.9
reading angle
The angular rotation of a symbol in an axis relative to a scan line. Three different reading angles, tilt, skew and pitch
are illustrated in figure 1. Tilt refers to rotation around the z axis, skew to rotation around the x axis and pitch to
2 © ISO/IEC 2001 – All rights reserved
rotation around the y axis.
See D in figure B.3.
from the scanner exit window. See E in figure B.3.
The projection of a laser beam to create multiple, nearly parallel, scan lines instead of a single line.
The distance from the exit window to the beginning of the depth of field. See A in figure 2.
The distance from the exit window to the end of the depth of field. See R in figure 2.
to the reading end of the scanner.
For example, decode redundancy of 2 requires two identical decodes.
the symbol .g. wand or light pen.
For the purposes of this part of ISO/IEC 15423, the definitions given in EN 1556 and the following apply.

skew pitch
tilt
Figure 1 — Reading angles
3.10
reading diagram
The graphical representation of the reading zone for a specific X dimension (or other parameters) of the bar code
symbol.
¾
¾
¾
¾
¾
¾
¾
.
3.11
reading zone
eF
© ISO/IEC 2001 – All rights reserved 3
MNOP in igur 2.
The whole area in front of the exit window of a non-contact scanner in which defined symbols can be read. See zone
See Annex B
Symbology.
Ambient light level
Symbol contrast value
Skew, tilt and pitch angles
X dimension (in mm)
Reading distance, measured on the z axis
Measurements made from the exit window of the reader
The parameters of the reading diagram are:

TwoO
axis
Scanner
N
C
M
P
A
B
R
Reading zone
Figure 2 — Example of reading zone (MNOP)
Certain application requirements, for example in automated conveyor scanning systems, may restrict the effective
4 © ISO/IEC 2001 – All rights reserved
reading zone to that shown in Figure 3 (MNO’P’).
NOTE
Two
axis
Scanner
N
O’
C´
M
A B
R
Restricted reading zone
Figure 3 — Example of restricted reading zone (MNO’P’)
3.12
read rate
3.13
resolution
3.14
scan
(Noun): A single pass of the scanning beam over the symbol or a portion of the symbol, or a single image capture
3.15
scan attempt
A single pass of the scanner relative to the symbol (or vice versa), or a single activation of the scanner for a period
3.16
scanning rate
© ISO/IEC 2001 – All rights reserved 5
per second.
The number of times the bar code symbol is scanned per second. It is expressed in scans per second, or scan lines
not exceeding two seconds, e.g. triggering, depending on the application.
image capture device.
(Verb): To pass the scanning beam over the symbol or a portion of the symbol, or to capture a single image with an
with an image capture device.
The width of the narrowest element capable of being read by the equipment under test.
The percentage representing the number of good reads per 100 attempts to read a particular symbol.
P’
3.17
scanning speed
The speed at which the scanning spot of a scanner with a single axis reading diagram is passed across a bar code
symbol.
4 Symbols and abbreviated terms
5 Categories of scanning equipment
In order to enable the most appropriate set of tests for a given scanning device or unit to be selected, scanners are
grouped for the purposes of this part of ISO/IEC 15423 into three categories. The basis for this categorisation is the
nature of the reading diagram applicable. Examples of various types of scanners are given in Annex B. Each
in progress when the symbol enters the reading zone, and ‘triggered’ scanners, where the symbol is already in the
5.1 Scanners with single axis reading diagram
These are defined as scanners with a reading diagram which extends as a single line from the exit window of the
The reading diagram for such scanners can be represented as a single line extending outwards from the exit window
.
5.2 Scanners with two axis reading diagram
These are defined as scanners with a reading diagram which extends in a single plane from the exit window of the
scanning action is created either by sweeping the scanner beam across the symbol in a direction nominally
5.3 Scanners with three axis reading diagram
These are defined as scanners with a reading diagram which extends in multiple planes from the exit window of the
y axes which are also perpendicular to each other. The scanning action is created either by sweeping the scanner
bars or in a pattern of scan lines at various angles, or by electronically sampling in turn individual photosensitive
6 © ISO/IEC 2001 – All rights reserved
The reading diagram for such scanners is the representation of a three-dimensional solid. See Figure B.3.
elements of an area array on which an image of the bar code symbol is focussed.
beam across the symbol in a series of nominally parallel scans in a direction nominally perpendicular to the height of the
scanner to the maximum reading distance along the z axis, and perpendicularly to this in both directions along the x and
The reading diagram for such scanners can be represented in a two-dimensional form. See Figure B.2.
on which an image of the bar code symbol is focussed.
perpendicular to the height of the bars, or by electronically sampling in turn individual elements of a photosensitive array
scanner to the maximum reading distance along the z axis and perpendicularly in both directions along the x axis. The
of the scanner. See Figure B.1
either the scanner or the symbol relative to the other in a direction nominally perpendicular to the height of the bars.
scanner to the maximum reading distance along the z axis. The scanning action therefore has to be created by moving
reading zone when the scanning operation is initiated.
category may be further subdivided into ‘continuously operating’ scanners, in which the scanning operation is already
CCD is an abbreviation of "Charge Coupled Device".

6 Test requirements
6.1 Test methods
Manufacturers’ test procedures should be in accordance with the requirements of ISO 9001 or ISO 9002 as
Where it is required to report the performance of a scanner or a decoder independently, the unit shall be tested in
Manufacturers may optionally test scanner or decoder performance independently using the equipment defined
in or but it should be noted that the results may not correspond exactly to those obtained when
6.2 Selection of equipment for testing
Tests shall be carried out on at least one unit which has been selected from a production batch in accordance with
6.3 Test conditions
6.3.1 Environment
6.3.2 Equipment configuration
¾
¾
¾
6.4 Test Charts
A set of bar code test charts is defined, which shall be used for tests indicated in the following sections. Test charts
shall be measured in accordance with ISO/IEC 15416, using a verifier complying with ISO/C 15426-1 and shall
eh
dmodulation shall be ignored and an overall grade shall be calculated based on remaining parameters).
© ISO/IEC 2001 – All rights reserved 7
an
aciev overall symbol grade 3,5 or better (in the case of test chart no. 2 the grades for symbol contrast, edge contrast
IE
digital output (where a scanner or decoder is being tested rather than a complete reader).
Logical conditions such as the type of output by the scanner, or sent to the decoder e.g. analogue waveform,
Physical conditions, e.g. type of interface, etc.;
Description of configuration, including type/model of scanner and decoder, and other measuring equipment;
The following information on the installation of the equipment under test shall be recorded:
time to ensure their dimensional stability during the test period.
Test charts to be used shall have been stored under the temperature and humidity conditions specified for a sufficient
humidity and ambient light conditions) and the test conditions shall be recorded as part of the test report.
Tests shall be conducted under manufacturer-specified environmental conditions (power supply, temperature, relative
given in ISO 2859-1.
It is in the manufacturer's interest to ensure that the unit selected is representative of its type. Guidance on sampling is NOTE
the manufacturer's quality control sampling scheme.
te steas a complete system.d
6.5.4.2 6.5.4.1
reported with the test results.
to scanning or decoding performance, as applicable, shall be reported. The decoder or scanner units used shall be
conjunction with one or more representative decoder or scanner unit(s) respectively, but only the parameters relative
Tests should wherever possible be carried out on a complete reading system comprising both scanner and decoder.
appropriate.
Measurement apertures shall be in accordance with Table 1 of ISO/IEC 15416. Decodability values for the test
symbols shall be not less than 0,80. Additionally, the Z dimension shall be measured and shall be within the
16388 ("Code 39"), but when equipment which is unable to process these symbologies is to be tested an equivalent
When measured with a light source of the same wavelength as that of the scanner under test, the reflectance and
symbol contrast values of the test charts shall be as specified below. The measured quiet zones shall be the
minimum width defined by the symbology specification (with tolerances of +1Z, -0Z), and the outer boundary of each
quiet zone shall be indicated by a vertical bar. This bar shall be at least 10Z wide and shall have a maximum
reflectance no greater than [R + max(R )] / 2, where R and R are as defined in ISO/IEC 15416. Test chartsDD
should be produced on dimensionally stable materials with image characteristics which are consistent within the
image or symbol area used for the test. As an example, Kodak Kodagraph Continuous Tone White Film (CTW7) is
one material that has been found to be suitable when backed with a black opaque material to minimise the effects of
¾
¾
¾
¾
¾
¾
¾
TEST CHART no. 1 - Resolution, scanning speed, reading diagram, reading angles
8 © ISO/IEC 2001 – All rights reserved
a Y dimension equal to 1,5 times the symbol width.
This chart comprises two sets of symbols, one in each symbology, with a range of values of the X dimension and with
broad range of achievable image reflectances (continuous tone).
surface finish (low gloss with low surface roughness)
high image sharpness (edge definition or acuity)
high consistency of image reflectance
high consistency of substrate surface reflectance
high substrate opacity (minimised show-through)
high dimensional stability
When selecting materials for this use it is important to consider:
show-through.
min min
parameter values (e.g. X dimension) beyond those specified.
set of test symbols in any other appropriate symbology may be used. Manufacturers may extend the range of symbol
tolerances specified for the test chart in question. Symbols shall comply with ISO/IEC 15417 ("Code 128") or ISO/IEC

Table 1 — Parameters for Test Chart no. 1
Parameter Value
± 0,01 , i.e. the maximum value of Z is (X + 0,01 mm) and the minimum value
± 0,05Z
± 0,02Z
R±
R±
R.
TEST CHART no. 2 - Symbol Contrast
This group of charts comprises two sets of symbols, one in each symbology, each with two values of X dimension
and, for each value of X, with eight different nominal values of symbol contrast as shown in Table 3 below. The
or light reflectance tolerances. The values of symbol contrast, R and R shall be measured using a light source
of 660 nanometres peak wavelength and stated on the Test Charts. Values of symbol contrast when measured at
633 nanometres and 900 nanometres with the same apertures shall also be stated on the Test Charts. The

© ISO/IEC 2001 – All rights reserved 9
measurement geometry shall be as defined in ISO/IEC15416.
min max
tolerance on symbol contrast shall be ±4 percentage points and this will limit the combined effect of the individual dark
min max
are as defined in ISO/IEC 15416 and R NOTE
6 symbol characters including start and stop Symbol content
min
3% 3%
max
5% 85%
3:1 in the case of Code 39 or other two width symbologies Wide:narrow ratio
1,5 times symbol width (excluding quiet zones) Y dimension
tolerance
Average bar width
Element width tolerance
of Z is (X - 0,01 mm)
mm
Step tolerance
from 0,10 mm to 0,50 mm in steps of 0,05 mm X dimension
Code 39 and Code 128 Symbology

Table 2 — Parameters for Test Chart no. 2
Parameter Value
± 0,05Z
± 0,02Z
20 mm
±
R and R
R and R
±
Table 3 — Symbol contrast
Nominal SymbolRRISO/IEC 15416
max min
Contrast Symbol Contrast
grade
10 © ISO/IEC 2001 – All rights reserved
10% 20% 10%
10% 25% 15%
10% 30% 20%
10% 35% 25%
10% 57% 47%
60% 80% 20%
55% 80% 25%
50% 80% 30%
33% 80% 47%
6 symbol characters including start and stop Symbol content
tolerances
4 percentage points but subject to overriding symbol contrast tolerance min max
min max
as per Table 3 below
tolerance
4 percentage points
Symbol contrast
as per Table 3 below Symbol contrast
3:1 in the case of Code 39 or other two width symbologies Wide:narrow ratio
Y dimension
tolerance
Average bar width
Element width tolerance
0,20 mm and 0,40 mm X dimension
Code 39 and Code 128 Symbology

6.5 Test equipment
6.5.1 Test equipment for scanners with single axis reading diagram
A rotating drum of 60 mm diameter (or greater), or a support capable of linear movement, as appropriate to the
physical construction of the scanner, to which the test symbol or scanner under test can be affixed with the bar
height perpendicular to the direction of rotation or movement, together with means of measuring the speed of the
A means of supporting the scanner or the test symbol to ensure that the scanning beam passes through the
symbol, together with means of varying and measuring the skew angle of the scanning beam relative to a plane
tangential to the surface of the symbol at the point where the scanning beam meets the symbol, and of varying
6.5.2 Test equipment for scanners with two axis reading diagram
and passing through it, together with means of measuring the position and angle of the symbol in two dimensions
6.5.3 Test equipment for scanners with three axis reading diagram
Equipment similar to that defined in but capable of movement in three axes, together with means of measuring
6.5.4 Additional test equipment
6.5.4.1 Test equipment for testing a scanner independently of a decoder
In order to test a scanner independently of a decoder, an oscilloscope connected to display the digital signal from the
scanner, and means of recording and analysis of the widths of the individual pulses in the signal in appropriate time
6.5.4.2 Test equipment for testing a decoder independently of a scanner
In order to test a decoder independently of a scanner, a signal generator is required. The output from the signal
generator shall emulate the bar/space pattern of a correctly encoded bar code symbol. The emulation shall comply
with the specification of the symbology under test. The data represented in the pulse string(s) should cover the
complete character set of the symbology and enable the decoder's processing of optional features of the symbology
to be tested. The electrical characteristics of the pulse string shall be adapted to the interface requirements of the
6.5.5 Test equipment for complete reading systems
Complete reading systems shall be tested using the equipment specified in to as appropriate for the type
of scanner together with auxiliary equipment which will enable the data output from the reading system to be
© ISO/IEC 2001 – All rights reserved 11

ascertained.
6.5.4 6.5.1
ascertained is also required.
decoder as specified by the manufacturer. Auxiliary equipment which will enable the data output by the decoder to be
units are required.
the position and angle of the test symbol in three dimensions relative to the scanner face.
6.5.2
relative to the scanner face.
symbol can be affixed perpendicular to the central axis of the plane and with the bar height perpendicular to the plane
A support capable of movement in two axes of the plane containing the scanning beam of the scanner, to which a test
and measuring the distance between the scanner face and the symbol.
b)
symbol relative to the scanner.
a)
be recorded.
The accuracy and resolution of test equipment shall be appropriate for the measurements being performed, and shall

6.6 Test criteria
The test criteria to be applied in order to decide whether or not a test symbol has been successfully scanned or read
are defined below. Where complete reading systems comprising both scanner and decoder units are to be tested,
the condition defined in shall apply. Where scanner units are to be tested without a decoder, the condition
6.6.1 Test criterion for complete reading systems and decoders
The test criterion is met if the read rate equals or exceeds 80% based on a minimum of 10 scan attempts. Any
6.6.2 Test criterion for scanners
The test principle is based on the extent to which the Z module is distorted when measured at the scanner digital
output. An appropriate test bar code symbol is fixed on the test equipment with the bar height perpendicular to the
An oscilloscope is connected to the digital output of the scanner to enable the widths of the pulses corresponding to

c) Using these time measurements, compute the decodability measure and grade for that symbol character, using
Annex C contains a hypothetical example, using the nomenclature of ISO/IEC 15416, and based on a Code 128
6.7 Parameters to be tested and test methods
Table 4 — Parameters to be tested for various categories of scanner
Parameter single axis two axis three axis
xxx
x
xxx
Tilt
xxx
xxx
xxx
It should be noted that these parameters are interdependent to varying degrees, e.g. resolution and scanning speed,
12 © ISO/IEC 2001 – All rights reserved
depth of field and symbol contrast, and the test results should record the values of all relevant variables.
The tests are described in more detail in the following sections.
Skew
Pitch
Reading Diagram
Scanning Speed
Resolution
Table 4 shows the parameters to be tested for each category of scanner.
symbol character.
the method specified in ISO 15416. Each character must receive a grade of 2,0 or better for this scan pass.
Measure the scan duration of each bar and space element of the character. b)
Measure the overall scan duration of the character. a)
For each symbol character:
individual elements of the symbol to be measured in appropriate time units.
direction of movement or to the scan line. The Z dimension used shall be reported with the results of the test.
misreads shall be noted and are grounds for rejecting the system for the conditions tested.
shall apply. 6.6.1 shall apply. Where decoder units are to be tested, the condition defined in 6.6.2 defined in
6.6.1
6.7.1 Scanners with single axis reading diagram
6.7.1.1 Resolution
This test is designed to report the minimum element width capable of being resolved by the equipment under test.
angles shall be 0° ± 2° The skew angle shall be such as to avoid direct reflection from the bar code substrate and
shall be reported with the result of the test. A series of test bar code symbols from test chart no. 1, with a set of Z
The test symbol with the highest Z value is fixed on the test equipment with the bar height perpendicular to the
direction of movement so that the axis of the scanner exit window will pass through the midpoint of the bar
height.
c) The test equipment is set in motion at a speed corresponding to the conditions of use for which the scanner is
If the test criterion in is not met, then the distance "d" is progressively increased until the test criterion is met;
if it is not met at all before the distance "d" has reached a value substantially exceeding the likely conditions of
If the test criterion in is met, the test is repeated from step a) using the test symbol with the next lower Z
f) The resolution of the scanner is defined as the "Z" dimension of the test symbol with the lowest Z value for which
The test results should report the resolution in mm., the skew angle, and record the minimum distance "d" at which
6.7.1.2 Scanning Speed
This test is designed to report the minimum and maximum scanning speeds of the equipment. The test equipment
described in 6.5.1 shall be used and shall be set up as described in . A test bar code symbol from test chart
no. 1 with a Z dimension equal to or greater than the resolution of the equipment shall be used. The Z dimension
The test bar code symbol is fixed on the test equipment with the bar height perpendicular to the direction of

c) The test equipment is set in motion and its speed is varied as necessary in order to determine the minimum and
The test results should report minimum and maximum scanning speeds in mm/s. and should record the Z dimension
© ISO/IEC 2001 – All rights reserved 13

of the test symbol used, the skew angle and the distance "d".
is met. 6.6 maximum speeds at which the test criterion in
above. 6.7.1.1 resolution test in
The distance "d" between scanner and symbol shall be adjusted to be equal to that recorded with the result of the b)
movement so that the axis of the scanner exit window will pass through the midpoint of the bar height.
a)
used shall be reported with the result of the test.
6.7.1.1
the test criterion is met with the test symbol with the Z value equal to the resolution of the scanner.
is met. 6.6 the criterion in
value.
6.6 e)
use of the scanner, the test is repeated from step a) using the test symbol with the next lower Z value.
6.6 d)
intended.
The distance "d" between scanner exit window and symbol shall be adjusted to a minimum. b)
a)
dimensions from 0,3 mm to 0,10 mm (or other values appropriate to the equipment under test) shall be used.
.
shall be used. The scanner shall be mounted so as to ensure that tilt and pitch 6.5.1 The test equipment described in

6.7.1.3 Reading diagram
This test is designed to determine the maximum and minimum reading distances and depth of field of the equipment
under test. The test equipment described in shall be used and shall be set up as described in . A
reading diagram shall be determined using each of three or more test bar code symbols from test chart no. 1 with
different values of measured nominal dimension. The lowest Z dimension shall be equal to the resolution of the
scanner from , the largest Z dimension shall be as specified by the manufacturer, and that of the third and
subsequent symbols shall be approximately evenly spaced between the first two. The Z dimensions used shall be
The test symbol is fixed on the test equipment with the bar height perpendicular to the direction of movement so

c) The scanner is activated and the test equipment set in motion at a speed within the range determined in
.
If the test criterion in is not met, then the distance "d" is progressively increased to the value d1 at which the

f)
The test results should report, for each Z dimension used for the test, the minimum and maximum reading distances
and the depth of field as the difference between these reading distances in mm; the reading diagram should
from test chart no. 2, and may be determined for variations in other parameters such as reading angles etc. and the
6.7.1.4 Symbol contrast
This test is designed to report the minimum values of symbol contrast at which the equipment under test can read.
angles shall be 0° ± 2° The skew angle shall be such as to avoid direct reflection from the bar code substrate and
shall be reported with the result of the test. A series of test bar code symbols from test chart no. 2, with the Z
dimension closest to 1,5 times the resolution of the equipment as determined in shall be used. The test shall
be performed twice, first with the subset of test symbols with decreasing values of R and next with the subset of
.
The test symbol with the highest symbol contrast value is fixed on the test equipment with the bar height
perpendicular to the direction of movement so that the axis of the scanner exit window will pass through the
The distance "d" between scanner exit window and symbol shall be adjusted to the midpoint between the
.
14 © ISO/IEC 2001 – All rights reserved
6.7.1.3 minimum and maximum reading distances for the Z dimension in use, as determined in
b)
midpoint of the bar height.
a)
min
test symbols with increasing values of R
max
6.7.1.1
.
shall be used. The scanner shall be mounted so as to ensure that tilt and pitch 6.5.1 The test equipment described in
values of such variables should be recorded with the test results.
Note that additional reading diagrams should be determined for different values of symbol contrast using test symbols
represent the limits of the reading zone.
The distance d2 corresponds to the maximum reading distance of the equipment. g)
The distance "d" is then progressively increased to the highest value, d2, at which the test criterion is still met.
The distance d1 corresponds to the minimum reading distance of the equipment. e)
test criterion is first met.
6.6 d)
6.7.1.2 accordance with
The distance "d" between scanner and symbol shall be adjusted to a minimum. b)
that the axis of the scanner exit window will pass through the midpoint of the bar height.
a)
For each symbol:
reported with the result of the test.
6.7.1.1
6.7.1.1 6.5.1
c) The test equipment is set in motion at a speed corresponding to the conditions of use for which the scanner is
If the test criterion in is met, then the test is repeated from step a) using test symbols with decreasing symbol
The test results should report the lowest symbol contrast value, the Z dimension, the skew angle, and record the
distance "d" at which the test measurements were made. If different results are obtained with the two subsets of test
symbols, both values of minimum symbol contrast shall be stated together with the corresponding values of R and
R.
6.7.1.5 Reading angles
defined under step a). The test equipment described in shall be used and shall be set up as described in
. The equipment under test is fixed mounted in a position such that the test symbol is on the axis of the
scanning beam at a distance "d" from the exit window midway between the minimum and maximum reading
distances. A test bar code symbol from test chart no. 1 with a Z dimension equal to or greater than the resolution of
°
bars perpendicular to the direction of movement) and pitch and skew angles of 0° or (depending on which is
.
c) °
smaller steps if appropriate) around the axis corresponding to the reading angle under test until the lowest and
6.7.2 Scanners with two axis reading diagram
6.7.2.1 Resolution
This test is designed to report the minimum element width capable of being resolved by the equipment under test.
...