SIST EN 62220-1-2:2007

Medical electrical equipment - Characteristics of digital X-ray imaging devices -- Part 1-2: Determination of the detective quantum efficiency - Detectors used in mammography

This part of IEC 62220 specifies the method for the determination of the DETECTIVE QUANTUM EFFICIENCY (DQE) of DIGITAL X-RAY IMAGING DEVICES as a function of AIR KERMA and of SPATIAL FREQUENCY for the working conditions in the range of the medical application as specified by the MANUFACTURER. The intended users of this part of IEC 62220 are manufacturers and well equipped test laboratories. This Part 1-2 is restricted to DIGITAL X-RAY IMAGING DEVICES that are used for mammographic imaging such as but not exclusively, CR systems, direct and indirect flat panel detector based systems, scanning systems (CCD based or photon-counting). This part of IEC 62220 is not applicable to - DIGITAL X-RAY IMAGING DEVICES intended to be used in general radiography or in dental radiography; - computed tomography; and - devices for dynamic imaging (where series of images are acquired, as in fluoroscopic or cardiac imaging).

Medizinische elektrische Geräte - Merkmale digitaler Röntgenbildgeräte - Teil 1-2: Bestimmung der detektiven Quanten-Ausbeute - Bildempfänger für Mammographieeinrichtungen

Appareils électromédicaux - Caractéristiques des dispositifs d'imagerie numérique à rayonnement X -- Partie 1-2: Détermination de l'efficacité quantique de détection - Détecteurs utilisés en mammographie

Spécifie la méthode de la détermination de l'efficacite quantique de détection (EQD) des dispositifs d'imagerie numérique à rayons X en fonction du kerma dans l'air et de la fréquence spatiale pour les conditions de fonctionnement dans la gamme des applications médicales, suivant les spécifications du fabricant. Les utilisateurs prévus de la présente partie de la CEI 62220 sont les fabricants et les laboratoires d'essai bien équipés. Cette Partie 1-2 est limitée aux dispositifs d'imagerie numérique à rayonnement X utilisés dans l'imagerie mammaire, tels que, mais pas exclusivement, les systèmes à écrans photo stimulables (connus sous la désignation de 'Computer Tomography', CR), les systèmes à base de détecteur à panneau plat direct ou indirect, les systèmes de balayage (à base de dispositif à transfert de charge (CCD en anglais) ou à comptage de photons). La présente partie de la CEI 62220 n'est pas applicable: - aux dispositifs d'imagerie numérique à rayonnement X destinés à être utilisés en radiographie générale ou en radiographie dentaire; - à la tomodensitométrie; et - aux dispositifs d'imagerie dynamique (où des ensembles d'images sont acquis, comme dans l'imagerie radioscopique ou cardiaque).

Električna medicinska oprema – Karakteristike digitalnih rentgenskih naprav – 1-2. del: Določanje kvantnega izkoristka zaznavanja – mamografski detektor (IEC 62220-1-2:2007)

General Information

• Status: Published
• Publication Date: 09-Oct-2007
• ICS: 11.040.50 - Radiographic equipment
• Technical Committee: IEMO - Electrical equipment in medical practice
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 02-Oct-2007
• Due Date: 07-Dec-2007
• Completion Date: 10-Oct-2007
• Directive: 93/42/EEC - Council Directive 93/42/EEC of 14 June 1993 concerning medical devices
• Ref Project: EN 62220-1-2:2007 - Medical electrical equipment - Characteristics of digital X-ray imaging devices - Part 1-2: Determination of the detective quantum efficiency - Detectors used in mammography

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN 62220-1-2:2007
01-november-2007
(OHNWULþQDPHGLFLQVNDRSUHPD±.DUDNWHULVWLNHGLJLWDOQLKUHQWJHQVNLKQDSUDY±
GHO'RORþDQMHNYDQWQHJDL]NRULVWND]D]QDYDQMD±PDPRJUDIVNLGHWHNWRU,(&

Medical electrical equipment - Characteristics of digital X-ray imaging devices -- Part 1-2:
Determination of the detective quantum efficiency - Mammography detectors (IEC 62220
-1-2:2007)
Medizinische elektrische Geräte - Merkmale digitaler Röntgenbildgeräte - Teil 1-2:
Bestimmung der detektiven Quanten-Ausbeute - Bildempfänger für
Mammographieeinrichtungen (IEC 62220-1-2:2007)
Appareils électromédicaux - Caractéristiques des dispositifs d'imagerie numérique a
rayonnement X -- Partie 1-2: Détermination de l'efficacité quantique de détection -
Détecteurs utilisés en mammographie (IEC 62220-1-2:2007)
Ta slovenski standard je istoveten z: EN 62220-1-2:2007
ICS:
11.040.50 Radiografska oprema Radiographic equipment
SIST EN 62220-1-2:2007 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------

EUROPEAN STANDARD
EN 62220-1-2

NORME EUROPÉENNE
September 2007
EUROPÄISCHE NORM

ICS 11.040.50


English version


Medical electrical equipment -
Characteristics of digital X-ray imaging devices -
Part 1-2: Determination of the detective quantum efficiency -
Detectors used in mammography
(IEC 62220-1-2:2007)


Appareils électromédicaux -  Medizinische elektrische Geräte -
Caractéristiques des dispositifs Merkmale digitaler Röntgenbildgeräte -
d'imagerie numérique à rayonnement X - Teil 1-2: Bestimmung
Partie 1-2: Détermination der detektiven Quanten-Ausbeute -
de l'efficacité quantique de détection - Bildempfänger
Détecteurs utilisés en mammographie für Mammographieeinrichtungen
(CEI 62220-1-2:2007) (IEC 62220-1-2:2007)




This European Standard was approved by CENELEC on 2007-09-01. CENELEC members are bound to comply
with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard
the status of a national standard without any alteration.

Up-to-date lists and bibliographical references concerning such national standards may be obtained on
application to the Central Secretariat or to any CENELEC member.

This European Standard exists in three official versions (English, French, German). A version in any other
language made by translation under the responsibility of a CENELEC member into its own language and notified
to the Central Secretariat has the same status as the official versions.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Cyprus, the
Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain,
Sweden, Switzerland and the United Kingdom.

CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung

Central Secretariat: rue de Stassart 35, B - 1050 Brussels


© 2007 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 62220-1-2:2007 E

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EN 62220-1-2:2007 - 2 -

Foreword
The text of document 62B/649/FDIS, future edition 1 of IEC 62220-1-2, prepared by SC 62B, Diagnostic
imaging equipment, of IEC TC 62, Electrical equipment in medical practice, was submitted to the
IEC-CENELEC parallel vote and was approved by CENELEC as EN 62220-1-2 on 2007-09-01.
The following dates were fixed:
– latest date by which the EN has to be implemented
at national level by publication of an identical
(dop) 2008-06-01
national standard or by endorsement
– latest date by which the national standards conflicting
with the EN have to be withdrawn (dow) 2010-09-01
In this standard, terms printed in SMALL CAPITALS are used as defined in IEC/TR 60788, in Clause 3 of this
standard or other IEC publications referenced in the Index of defined terms. Where a defined term is used
as a qualifier in another defined or undefined term it is not printed in SMALL CAPITALS, unless the concept
thus qualified is defined or recognized as a “derived term without definition”.
NOTE  Attention is drawn to the fact that, in cases where the concept addressed is not strongly confined to the definition given in
one of the publications listed above, a corresponding term is printed in lower-case letters.
In this standard, certain terms that are not printed in SMALL CAPITALS have particular meanings, as follows:
– "shall" indicates a requirement that is mandatory for compliance;
– "should" indicates a strong recommendation that is not mandatory for compliance;
– "may" indicates a permitted manner of complying with a requirement or of avoiding the need to
comply;
– "specific" is used to indicate definitive information stated in this standard or referenced in other
standards, usually concerning particular operating conditions, test arrangements or values connected
with compliance;
– "specified" is used to indicate definitive information stated by the manufacturer in accompanying
documents or in other documentation relating to the equipment under consideration, usually
concerning its intended purposes, or the parameters or conditions associated with its use or with
testing to determine compliance.
This European Standard has been prepared under a mandate given to CENELEC by the European
Commission and the European Free Trade Association and covers essential requirements of
EC Directive MDD (93/42/EEC). See Annex ZZ.
Annexes ZA and ZZ have been added by CENELEC.
__________
Endorsement notice
The text of the International Standard IEC 62220-1-2:2007 was approved by CENELEC as a European
Standard without any modification.
In the official version, for Bibliography, the following note has to be added for the standard indicated:
IEC 61262-5 NOTE  Harmonized as EN 61262-5:1994 (not modified).
__________

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- 3 - EN 62220-1-2:2007
Annex ZA
(normative)

Normative references to international publications
with their corresponding European publications

The following referenced documents are indispensable for the application 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.

NOTE  When an international publication has been modified by common modifications, indicated by (mod), the relevant EN/HD
applies.

Publication Year Title EN/HD Year

1) 2)
IEC 60336 - Medical electrical equipment - X-ray tube EN 60336 2005
assemblies for medical diagnosis -
Characteristics of focal spots


1) 2)
IEC 60601-2-45 - Medical electrical equipment - EN 60601-2-45 2001
Part 2-45: Particular requirements for the
safety of mammographic X-ray equipment
and mammographic stereotactic devices


IEC/TR 60788 2004 Medical electrical equipment - - -
Glossary of defined terms


IEC 61267 2005 Medical diagnostic X-ray equipment - EN 61267 2006
Radiation conditions for use in the
determination of characteristics


IEC 62220-1 2003 Medical electrical equipment - EN 62220-1 2004
Characteristics of digital X-ray imaging
devices -
Part 1: Determination of the detective
quantum efficiency


ISO 12232 1998 Photography - Electronic still-picture - -
cameras - Determination of ISO speed



1)
Undated reference.
2)
Valid edition at date of issue.

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EN 62220-1-2:2007 - 4 -
Annex ZZ
(informative)

Coverage of Essential Requirements of EC Directives

This European Standard has been prepared under a mandate given to CENELEC by the European
Commission and the European Free Trade Association and within its scope the standard covers all
relevant essential requirements as given in Annex I of the EC Directive 93/42/EEC.

Compliance with this standard provides one means of conformity with the specified essential
requirements of the Directive concerned.

WARNING: Other requirements and other EC Directives may be applicable to the products falling within
the scope of this standard.

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INTERNATIONAL IEC
STANDARD
CEI



62220-1-2
NORME


First edition
INTERNATIONALE

Première édition
2007-06


Medical electrical equipment –
Characteristics of digital X-ray imaging devices –
Part 1-2:
Determination of the
detective quantum efficiency –
Detectors used in mammography

Appareils électromédicaux –
Caractéristiques des dispositifs
d’imagerie numérique à rayonnement X –
Partie 1-2:
Détermination de l’efficacité
quantique de détection –
Détecteurs utilisés en mammographie
PRICE CODE
U
CODE PRIX
Commission Electrotechnique Internationale
International Electrotechnical Commission
МеждународнаяЭлектротехническаяКомиссия
For price, see current catalogue
Pour prix, voir catalogue en vigueur

---------------------- Page: 6 ----------------------

– 2 – 62220-1-2 © IEC:2007
CONTENTS
FOREWORD.3
INTRODUCTION.5

1 Scope.6
2 Normative references .6
3 Terminology and definitions .7
4 Requirements .9
4.1 Operating conditions .9
4.2 X-RAY EQUIPMENT .9
4.3 RADIATION QUALITY .9
4.4 TEST DEVICE .10
4.5 Geometry .11
4.6 IRRADIATION conditions.12
5 Corrections of RAW DATA .15
6 Determination of the DETECTIVE QUANTUM EFFICIENCY.16
6.1 Definition and formula of DQE(u,v) .16
6.2 Parameters to be used for evaluation .16
6.3 Determination of different parameters from the images.17
7 Format of conformance statement .21
8 Accuracy .21

Annex A (normative) Determination of LAG EFFECTS.22
Annex B (informative) Calculation of the input NOISE POWER SPECTRUM.25

Bibliography.26

Terminology – Index of defined terms .28

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62220-1-2 © IEC:2007 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________

MEDICAL ELECTRICAL EQUIPMENT –
CHARACTERISTICS OF DIGITAL X-RAY IMAGING DEVICES –

Part 1-2: Determination of the detective quantum efficiency –
Detectors used in mammography


FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
in the subject dealt with may participate in this preparatory work. International, governmental and non-
governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely
with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with an IEC Publication.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 62220-1-2 has been prepared by subcommittee 62B: Diagnostic
imaging equipment, of IEC technical committee 62: Electrical equipment in medical practice.
The text of this standard is based on the following documents:
FDIS Report on voting
62B/649/FDIS 62B/656/RVD

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.

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– 4 – 62220-1-2 © IEC:2007
A list of all parts of the IEC 62220 series, published under the general title Medical electrical
equipment – Characteristics of digital X-ray imaging devices, can be found on the IEC
website.
In this standard, terms printed in SMALL CAPITALS are used as defined in IEC 60788, in Clause
3 of this standard or other IEC publications referenced in the Index of defined terms. Where a
defined term is used as a qualifier in another defined or undefined term it is not printed in
SMALL CAPITALS, unless the concept thus qualified is defined or recognized as a “derived term
without definition”.
NOTE Attention is drawn to the fact that, in cases where the concept addressed is not strongly confined to the
definition given in one of the publications listed above, a corresponding term is printed in lower-case letters.
In this standard, certain terms that are not printed in SMALL CAPITALS have particular
meanings, as follows:
– "shall" indicates a requirement that is mandatory for compliance;
– "should" indicates a strong recommendation that is not mandatory for compliance;
– "may" indicates a permitted manner of complying with a requirement or of avoiding the
need to comply;
– "specific" is used to indicate definitive information stated in this standard or referenced in
other standards, usually concerning particular operating conditions, test arrangements or
values connected with compliance;
– "specified" is used to indicate definitive information stated by the manufacturer in
accompanying documents or in other documentation relating to the equipment under
consideration, usually concerning its intended purposes, or the parameters or conditions
associated with its use or with testing to determine compliance.
The committee has decided that the contents of this publication will remain unchanged until
the maintenance result 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.

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62220-1-2 © IEC:2007 – 5 –
INTRODUCTION
DIGITAL X-RAY IMAGING DEVICES are increasingly used in medical diagnosis and will widely
replace conventional (analogue) imaging devices such as screen-film systems or analogue X-
RAY IMAGE INTENSIFIER television systems in the future. It is necessary, therefore, to define
parameters that describe the specific imaging properties of these DIGITAL X-RAY IMAGING
DEVICES and to standardize the measurement procedures employed.
There is growing consensus in the scientific world that the DETECTIVE QUANTUM EFFICIENCY
(DQE) is the most suitable parameter for describing the imaging performance of an X-ray
imaging device. The DQE describes the ability of the imaging device to preserve the signal-to-
NOISE ratio from the radiation field to the resulting digital image data. Since in X-ray imaging,
the NOISE in the radiation field is intimately coupled to the AIR KERMA level, DQE values can
also be considered to describe the dose efficiency of a given DIGITAL X-RAY IMAGING DEVICE.
NOTE In spite of the fact that the DQE is widely used to describe the performance of imaging devices, the
connection between this physical parameter and the decision performance of a human observer is not yet
)
1
completely understood [1], [3].
The DQE is already widely used by manufacturers to describe the performance of their DIGITAL
X-RAY IMAGING DEVICES. The specification of the DQE is also required by regulatory agencies
(such as the Food and Drug Administration (FDA)) for admission procedures. However, there
is presently no standard governing either the measurement conditions or the measurement
procedure with the consequence that values from different sources may not be comparable.
This standard has therefore been developed in order to specify the measurement procedure
together with the format of the conformance statement for the DETECTIVE QUANTUM EFFICIENCY
of DIGITAL X-RAY IMAGING DEVICES.
In the DQE calculations proposed in this standard, it is assumed that system response is
measured for objects that attenuate all energies equally (task-independent) [5].
This standard will be beneficial for manufacturers, users, distributors and regulatory agencies.
It is the second document out of a series of three related standards:
RADIOGRAPHY, excluding MAMMOGRAPHY and
• Part 1, which is intended to be used in
RADIOSCOPY;
• the present Part 1-2, which is intended to be used for MAMMOGRAPHY;
• Part 1-3, which is intended to be used for dynamic imaging detectors.
These standards can be regarded as the first part of the family of 62220 standards describing
the relevant parameters of DIGITAL X-RAY IMAGING DEVICES.
———————
)
1
Figures in square brackets refer to the bibliography.

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– 6 – 62220-1-2 © IEC:2007
MEDICAL ELECTRICAL EQUIPMENT –
CHARACTERISTICS OF DIGITAL X-RAY IMAGING DEVICES –

Part 1-2: Determination of the detective quantum efficiency –
Detectors used in mammography

1 Scope
This part of IEC 62220 specifies the method for the determination of the DETECTIVE QUANTUM
EFFICIENCY (DQE) of DIGITAL X-RAY IMAGING DEVICES as a function of AIR KERMA and of SPATIAL
FREQUENCY for the working conditions in the range of the medical application as specified by
the MANUFACTURER. The intended users of this part of IEC 62220 are manufacturers and well
equipped test laboratories.
DIGITAL X-RAY IMAGING DEVICES that are used for mammographic
This Part 1-2 is restricted to
imaging such as but not exclusively, CR systems, direct and indirect flat panel detector based
systems, scanning systems (CCD based or photon-counting). This part of IEC 62220 is not
applicable to
– DIGITAL X-RAY IMAGING DEVICES intended to be used in general radiography or in dental
radiography;
– computed tomography;
and
– devices for dynamic imaging (where series of images are acquired, as in fluoroscopic or
cardiac imaging).
NOTE The devices noted above are excluded because they contain many parameters (for instance, beam
qualities, geometry, time dependence, etc.) which differ from those important for mammography. Some of these
techniques are treated in separate standards (IEC 62220-1 and IEC 62220-1-3) as has been done for other topics,
for instance for speed and contrast, in IEC and ISO standards.
2 Normative references
The following referenced documents are indispensable for the application 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 60336, Medical electrical equipment – X-ray tube assemblies for medical diagnosis –
Characteristics of focal spots
IEC TR 60788:2004, Medical electrical equipment – Glossary of defined terms
IEC 60601-2-45, Medical electrical equipment – Part 2-45: Particular requirements for the
safety of mammographic X-ray equipment and mammographic stereotactic devices
IEC 61267:2005, Medical diagnostic X-ray equipment – Radiation conditions for use in the
determination of characteristics

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62220-1-2 © IEC:2007 – 7 –
IEC 62220-1:2003, Medical electrical equipment – Characteristics of digital X-ray imaging
devices – Part 1: Determination of the detective quantum efficiency
ISO 12232:1998, Photography – Electronic still-picture cameras – Determination of ISO speed
3 Terms and definitions
For the purpose of this document, the terms and definitions given in IEC 60788 which are
listed in the Index of defined terms and the following apply.
3.1
CONVERSION FUNCTION
plot of the large area output level (ORIGINAL DATA) of a DIGITAL X-RAY IMAGING DEVICE versus
the number of exposure quanta per unit area (Q) in the DETECTOR SURFACE plane
NOTE 1 Q is to be calculated by multiplying the measured AIR KERMA excluding back scatter by the value given in
column 4 of Table 2.
NOTE 2 Many calibration laboratories, such as national metrology institutes, calibrate RADIATION METERS to
measure AIR KERMA.
[IEC 62220-1:2003, definition 3.2, modified]
3.2
DETECTIVE QUANTUM EFFICIENCY
DQE(u,v)
ratio of two NPS functions with the numerator being the NPS of the input signal at the
DETECTOR SURFACE of a digital X-ray detector after having gone through the deterministic filter
given by the system transfer function, and the denominator being the measured NPS of the
output signal (ORIGINAL DATA)
NOTE Instead of the two-dimensional DETECTIVE QUANTUM EFFICIENCY, often a cut through the two-
dimensional DETECTIVE QUANTUM EFFICIENCY along a specified line in the frequency plane is published.
[IEC 62220-1:2003, definition 3.3, modified]
3.3
DETECTOR SURFACE
accessible area which is closest to the IMAGE RECEPTOR PLANE
NOTE After removal of all parts (including the ANTI-SCATTER GRID and components for AUTOMATIC EXPOSURE
CONTROL, if applicable) that can be safely removed from the RADIATION BEAM without damaging the digital X-ray
detector.
[IEC 62220-1:2003, definition 3.4, modified]
3.4
DIGITAL X-RAY IMAGING DEVICE
device consisting of a digital X-ray detector including the protective layers installed for use in
practice, the amplifying and digitizing electronics, and a computer providing the ORIGINAL DATA
(DN) of the image
[IEC 62220-1:2003, definition 3.5]
3.5
IMAGE MATRIX
arrangement of MATRIX ELEMENTS preferentially in a Cartesian coordinate system
[IEC 62220-1:2003, definition 3.6, modified]

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– 8 – 62220-1-2 © IEC:2007
3.6
LAG EFFECT
influence from a previous image on a current one
[IEC 62220-1:2003, definition 3.7]
3.7
LINEARIZED DATA
ORIGINAL DATA to which the inverse CONVERSION FUNCTION has been applied
NOTE The LINEARIZED DATA are directly proportional to the AIR KERMA.
[IEC 62220-1:2003, definition 3.8]
3.8
MODULATION TRANSFER FUNCTION
MTF(u,v)
modulus of the generally complex optical transfer function, expressed as a function of SPATIAL
FREQUENCIES u and v
[IEC 62220-1:2003, definition 3.9]
3.9
NOISE
fluctuations from the expected value of a stochastic process
[IEC 62220-1:2003, definition 3.10]
3.10
NOISE POWER SPECTRUM
NPS
W(u,v)
modulus of the Fourier transform of the NOISE auto-covariance function. The power of NOISE,
contained in a two-dimensional SPATIAL FREQUENCY interval, as a function of the two-
dimensional frequency
NOTE In literature, the NOISE POWER SPECTRUM is often named “Wiener spectrum” in honour of the mathematician
Norbert Wiener.
[IEC 62220-1:2003, definition 3.11]
3.11
ORIGINAL DATA
DN
RAW DATA to which the corrections allowed in this standard have been applied
[IEC 62220-1:2003, definition 3.12]
3.12
PHOTON FLUENCE
Q
mean number of photons per unit area
[IEC 62220-1:2003, definition 3.13]
3.13
RAW DATA
PIXEL values read directly after the analogue-digital-conversion from the DIGITAL X-RAY IMAGING
DEVICE or counts from photon counting systems without any software corrections
[IEC 62220-1:2003, definition 3.14, modified]

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62220-1-2 © IEC:2007 – 9 –
3.14
SPATIAL FREQUENCY
u or v
inverse of the period of a repetitive spatial phenomenon. The dimension of the SPATIAL
FREQUENCY is inverse length
[IEC 62220-1:2003, definition 3.15]
4 Requirements
4.1 Operating conditions
The DIGITAL X-RAY IMAGING DEVICE shall be stored and operated according to the
MANUFACTURERS’ recommendations. The warm-up time shall be chosen according to the
recommendation of the MANUFACTURER. The operating conditions shall be the same as those
intended for clinical use and shall be maintained during evaluation as required for the specific
tests described herein.
DIGITAL X-RAY IMAGING DEVICE is operated
Ambient climatic conditions in the room where the
shall be stated together with the results.
4.2 X-RAY EQUIPMENT
For all tests described in the following subclauses, a CONSTANT POTENTIAL HIGH-VOLTAGE
GENERATOR shall be used (IEC 60601-2-45). The PERCENTAGE RIPPLE shall be equal to, or less
than, 4.
The NOMINAL FOCAL SPOT VALUE (IEC 60336) shall be not larger than 0,4.
For measuring the AIR KERMA calibrated RADIATION METERS shall be used. The uncertainty
(coverage factor 2) [2] of the measurement shall be less than 5 %.
NOTE 1 ”Uncertainty” and “coverage factor” are terms defined in the ISO Guide to the expression of uncertainty in
measurement [2].
NOTE 2 RADIATION METERS to read AIR KERMA are calibrated by many national metrology institutes.
4.3 RADIATION QUALITY
The RADIATION QUALITY shall be RQA-M 2 as specified in IEC 61267, if relevant for the clinical
use for that detector. Optionally other RADIATION QUALITIES may be used that are applied
clinically with the DIGITAL X-RAY IMAGING DEVICE, such as RQA-M 1, RQA-M 3, and RQA-M 4 or
RADIATION QUALITIES based on anode materials other than Molybdenum (see Table 1).
For the application of the RADIATION QUALITIES, refer to IEC 61267:2005-11.
NOTE According to IEC 61267 RADIATION QUALITIES RQA-M are defined by emitting TARGET of molybdenum, TOTAL
FILTRATION of 0,032 mm ± 0,002 mm molybdenum in the radiation source assembly, ADDED FILTER of 2 mm
aluminium (Table 1).

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