SIST EN 62127-1:2008
(Main)Ultrasonics - Hydrophones -- Part 1: Measurement and characterization of medical ultrasonic fields up to 40 MHz
Ultrasonics - Hydrophones -- Part 1: Measurement and characterization of medical ultrasonic fields up to 40 MHz
This part of IEC 62127 specifies methods of use of calibrated hydrophones for the measurement in liquids of acoustic fields generated by ultrasonic medical equipment operating in the frequency range up to 40 MHz. The objectives of this standard are: - to define a group of acoustic parameters that can be measured on a physically sound basis; - to define a second group of parameters that can be derived under certain assumptions from these measurements, and called derived intensity parameters; - to define a measurement procedure that may be used for the determination of acoustic pressure parameters; - to define the conditions under which the measurements of acoustic parameters can be made in the frequency range up to 40 MHz using calibrated hydrophones; - to define procedures for correcting, for limitations caused by the use of hydrophones with finite bandwidth and finite active element size.
Ultraschall - Hydrophone - Teil 1: Messung und Charakterisierung von medizinischen Ultraschallfeldern bis zu 40 MHz
Ultrasons - Hydrophones -- Partie 1: Mesures et caractérisation des champs ultrasonores médicaux jusqu'à 40 MHz
La CEI 62127-1:2007 spécifie les méthodes d'utilisation des hydrophones étalonnés permettant de mesurer, dans des liquides, les champs acoustiques générés par des appareils médicaux à ultrasons fonctionnant dans la gamme de fréquences jusqu'à 40 MHz. La présente norme a pour objectifs de:
- définir un groupe de paramètres acoustiques pouvant être mesurés sur une base physiquement sonore;
- définir un second groupe de paramètres pouvant être déduits, dans le cadre de certaines hypothèses, de ces mesures et appelés paramètres d'intensité dérivés;
- définir un mode opératoire de mesure permettant de déterminer les paramètres de pression acoustique;
- définir les conditions dans lesquelles les mesures des paramètres acoustiques peuvent être réalisées dans la gamme de fréquences jusqu'à 40 MHz à l'aide d'hydrophones étalonnés;
- et définir les modes opératoires de correction, dans le cas de limitations provoquées par l'utilisation d'hydrophones à largeur de bande finie et de taille d'élément actif finie. La CEI 62127-1, la CEI 62127-2 et la CEI 62127-3 ont été publiées conjointement. Ensemble, elles annulent et remplacent la CEI 60866:1987, la CEI 61101:1991, la CEI 61102:1991, la CEI 61220:1993 et la CEI 62092:2001. Le contenu du corrigendum (août 2008, disponible en anglais seulement) a été inclus dans cette norme. La version française n'a pas été soumise au vote.
Ultrazvok - Hidrofoni - 1. del: Meritve in karakterizacija medicinskih ultrazvočnih polj do 40 MHz (IEC 62127-1:2007)
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN 62127-1:2008
01-januar-2008
1DGRPHãþD
SIST EN 61101:2002
SIST EN 61220:2002
SIST EN 62092:2002
8OWUD]YRN+LGURIRQLGHO 0HULWYHLQNDUDNWHUL]DFLMDPHGLFLQVNLKXOWUD]YRþQLK
SROMGR0+] ,(&
Ultrasonics - Hydrophones - Part 1: Measurement and characterization of medical
ultrasonic fields up to 40 MHz (IEC 62127-1:2007)
Ultraschall - Hydrophone - Teil 1: Messung und Charakterisierung von medizinischen
Ultraschallfeldern bis zu 40 MHz (IEC 62127-1:2007)
Ultrasons - Hydrophones - Partie 1: Mesures et caractérisation des champs ultrasonores
médicaux jusqu'a 40 Mhz (IEC 62127-1:2007)
Ta slovenski standard je istoveten z: EN 62127-1:2007
ICS:
11.040.01 Medicinska oprema na Medical equipment in general
splošno
17.140.50 Elektroakustika Electroacoustics
SIST EN 62127-1:2008 en,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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EUROPEAN STANDARD
EN 62127-1
NORME EUROPÉENNE
October 2007
EUROPÄISCHE NORM
ICS 17.140.50 Partially supersedes EN 61101:1993, EN 61102:1993 + A1:1994, EN 61220:1995 and EN 62092:2001
English version
Ultrasonics -
Hydrophones -
Part 1: Measurement and characterization
of medical ultrasonic fields up to 40 MHz
(IEC 62127-1:2007)
Ultrasons - Ultraschall -
Hydrophones - Hydrophone -
Partie 1: Mesures et caractérisation Teil 1: Messung und Charakterisierung
des champs ultrasonores médicaux von medizinischen Ultraschallfeldern
jusqu'à 40 Mhz bis zu 40 MHz
(CEI 62127-1:2007) (IEC 62127-1:2007)
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 62127-1:2007 E
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EN 62127-1:2007 - 2 -
Foreword
The text of document 87/352/CDV, future edition 1 of IEC 62127-1, prepared by IEC TC 87, Ultrasonics,
was submitted to the IEC-CENELEC parallel Unique Acceptance Procedure and was approved by
CENELEC as EN 62127-1 on 2007-09-01.
EN 62127-1, EN 62127-2 and EN 62127-3 are being published simultaneously. Together these European
Standards cancel and replace EN 61101:1993, EN 61102:1993 + A1:1994, EN 61220:1995 and
EN 62092:2001.
The following dates were fixed:
– latest date by which the EN has to be implemented
at national level by publication of an identical
national standard or by endorsement (dop) 2008-06-01
– latest date by which the national standards conflicting
(dow) 2010-09-01
with the EN have to be withdrawn
Annex ZA has been added by CENELEC.
__________
Endorsement notice
The text of the International Standard IEC 62127-1:2007 was approved by CENELEC as a European
Standard without any modification.
In the official version, for Bibliography, the following notes have to be added for the standards indicated:
IEC 60601-2-37 NOTE Harmonized as EN 60601-2-37:2001 (not modified).
IEC 61157 NOTE Harmonized as EN 61157:1994 (not modified).
IEC 61161 NOTE Harmonized as EN 61161:2007 (not modified).
IEC 62359 NOTE Harmonized as EN 62359:2005 (not modified).
__________
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- 3 - EN 62127-1:2007
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
IEC 60050-801 1994 International Electrotechnical Vocabulary - -
(IEV) -
Chapter 801: Acoustics and electroacoustics
1) 2)
IEC 60565 - Underwater acoustics - Hydrophones - EN 60565 2007
Calibration in the frequency range 0,01 Hz
to 1 MHz
IEC/TR 60854 1986 Methods of measuring the performance of - -
ultrasonic pulse-echo diagnostic equipment
1)
IEC 61689 - Ultrasonics - Physiotherapy systems - Field EN 61689 2007
specifications and methods of measurement
in the frequency range 0,5 MHz to 5 MHz
1) 2)
IEC 61828 - Ultrasonics - Focusing transducers - EN 61828 2001
Definitions and measurement methods
for the transmitted fields
1) 2)
IEC 61846 - Ultrasonics - Pressure pulse lithotripters - EN 61846 1998
Characteristics of fields
1) 2)
IEC 61847 - Ultrasonics - Surgical systems - EN 61847 1998
Measurement and declaration of the basic
output characteristics
1) 2)
IEC 62127-2 - Ultrasonics - Hydrophones - EN 62127-2 2007
Part 2: Calibration for ultrasonic fields
up to 40 MHz
1) 2)
IEC 62127-3 - Ultrasonics - Hydrophones - EN 62127-3 2007
Part 3: Properties of hydrophones for
ultrasonic fields up to 40 MHz
ISO 16269-6 2005 Statistical interpretation of data - - -
Part 6: Determination of statistical tolerance
intervals
ISO/IEC Guide 98 1995 Guide to the expression of uncertainty in - -
measurement
1)
Undated reference.
2)
Valid edition at date of issue.
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IEC 62127-1
Edition 1.0 2007-08
INTERNATIONAL
STANDARD
Ultrasonics – Hydrophones –
Part 1: Measurement and characterization of medical ultrasonic fields up to
40 MHz
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
XC
ICS 17.140.50 ISBN 2-8318-9276-7
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– 2 – 62127-1 © IEC:2007(E)
CONTENTS
FOREWORD.5
INTRODUCTION.7
1 Scope and object.8
2 Normative references .8
3 Terms, definitions and symbols .9
4 List of symbols .24
5 Measurement requirements .26
5.1 Requirements for hydrophones and amplifiers .26
5.1.1 Introduction .26
5.1.2 General .26
5.1.3 Sensitivity of a hydrophone.26
5.1.4 Directional response of a hydrophone.26
5.1.5 Effective hydrophone radius .27
5.1.6 Choice of the size of a hydrophone active element .27
5.1.7 Bandwidth .28
5.1.8 Linearity .28
5.1.9 Hydrophone signal amplifier .29
5.1.10 Hydrophone cable length and amplifiers .29
5.2 Requirements for positioning and water baths .29
5.2.1 General .29
5.2.2 Positioning systems.30
5.2.3 Water bath.31
5.3 Requirements for data acquisition and analysis systems .32
5.4 Recommendations for ultrasonic equipment being characterized .32
6 Measurement procedure.32
6.1 General .32
6.2 Preparation and alignment.33
6.2.1 Preparation.33
6.2.2 Aligning an ultrasonic transducer and a hydrophone.33
6.3 Measurement .33
6.4 Analysis .33
6.4.1 Corrections for restricted bandwidth and spatial resolution .33
6.4.2 Uncertainties .33
7 Beam characterization.34
7.1 General .34
7.2 Primary pressure parameters .35
7.2.1 General .35
7.2.2 Peak-compressional acoustic pressure and peak-rarefactional
acoustic pressure .36
7.2.3 Spatial-peak rms acoustic pressure .36
7.2.4 Non-linear propagation parameter .36
7.2.5 Intensity parameters using instantaneous acoustic pressure.37
7.2.6 Intensity parameters using pulse-pressure-squared integral .37
7.2.7 Derived ultrasonic power .39
8 Requirements for specific ultrasonic fields.40
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62127-1 © IEC:2007(E) – 3 –
8.1 General .40
8.2 Diagnostic fields.40
8.2.1 Simplified procedures and guidelines.40
8.2.2 Pulsed wave diagnostic equipment .41
8.2.3 Continuous wave diagnostic equipment .41
8.3 Therapy fields .42
8.3.1 Physiotherapy equipment .42
8.3.2 Hyperthermia.42
8.4 Surgical fields .42
8.4.1 Lithotripters and pressure pulse sources for other therapeutic
purposes .42
8.4.2 Low frequency surgical applications .43
8.5 Fields from other medical applications.43
9 Compliance statement .43
9.1 General .43
9.2 Maximum probable values .43
9.3 Sampling .44
Annex A (informative) General rationale .45
Annex B (informative) Hydrophones and positioning .47
Annex C (informative) Acoustic pressure and intensity.53
Annex D (informative) Voltage to pressure conversion .55
Annex E (informative) Correction for spatial averaging.60
Annex F (informative) Acoustic output parameters for multi-mode medical ultrasonic
fields in the absence of scan-frame synchronization .62
Annex G (informative) Propagation medium and degassing .68
Annex H (informative) Specific ultrasonic fields.69
Annex I (informative) Assessment of uncertainty in the acoustic quantities obtained by
hydrophone measurements.72
Annex J (informative) Transducer and hydrophone positioning systems.74
Annex K (informative) Beamwidth midpoint method.75
Bibliography.76
Figure 1 – Schematic diagram of the different planes and lines in an ultrasonic field
(see also IEC 61828) .11
Figure 2 – Schematic diagram of the method of determining pulse duration .35
Figure D.1 – A flow diagram of the hydrophone deconvolution process .56
Figure D.2 – Example of waveform deconvolution.59
Figure J.1 – Schematic diagram of the ultrasonic transducer and hydrophone degrees
of freedom .74
Table 1 – Acoustic parameters appropriate to various types of medical ultrasonic
equipment.34
Table B.1 – Typical specification data for hydrophones, in this case given at 1 MHz .52
Table C.1 – Properties of distilled or de-ionized water as a function of temperature.54
Table D.1 – Method of conversion from a double- to a single-sided spectrum .57
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Table D.2 – Method of conversion from a single- to a double-sided spectrum .58
Table F.1 – Main parameters defined in IEC standards .63
Table F.2 – List of parameters that are to be used or are to be deleted.64
Table K.1 – dB beamwidth levels for determining midpoints .75
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62127-1 © IEC:2007(E) – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ULTRASONICS – HYDROPHONES –
Part 1: Measurement and characterization of medical
ultrasonic fields up to 40 MHz
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 62127-1 has been prepared by IEC technical committee 87:
Ultrasonics.
IEC 62127-1, IEC 62127-2 and IEC 62127-3 are being published simultaneously. Together
these cancel and replace IEC 60866:1987, IEC 61101:1991, IEC 61102:1991, IEC 61220:1993
and IEC 62092:2001.
The text of this standard is based on the following documents:
Enquiry draft Report on voting
87/352/CDV 87/371/RVC
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
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– 6 – 62127-1 © IEC:2007(E)
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts of IEC 62127 series, published under the general title Ultrasonics –
Hydrophones, can be found on the IEC website.
NOTE Words in bold in the text are defined in Clause 3.
The committee has decided that the contents of this publication will remain unchanged until
the maintenance result date indicated on the IEC website 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.
A bilingual version of this publication may be issued at a later date.
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62127-1 © IEC:2007(E) – 7 –
INTRODUCTION
The main purpose of this part of IEC 62127 is to define various acoustic parameters that can
be used to specify and characterize ultrasonic fields propagating in liquids, and, in particular,
water, using hydrophones. Measurement procedures are outlined that may be used to
determine these parameters. Specific device related measurement standards, for example
IEC 61689, IEC 61157, IEC 61847 or IEC 62359, can refer to this standard for appropriate
acoustic parameters.
The philosophy behind this standard is the specification of the acoustic field in terms of
acoustic pressure parameters, acoustic pressure being the primary measurement quantity
when piezoelectric hydrophones are used to characterize the field. Of course, if other
measurement devices come into use in the future, a new standard with additional definitions
and procedures will be necessary. Examples of such devices would be thermistors,
thermocouples or optical hydrophones.
Intensity parameters are specified in this standard, but these are regarded as derived
quantities that are meaningful only under certain assumptions related to the ultrasonic field
being measured.
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ULTRASONICS – HYDROPHONES –
Part 1: Measurement and characterization of medical
ultrasonic fields up to 40 MHz
1 Scope and object
This part of IEC 62127 specifies methods of use of calibrated hydrophones for the
measurement in liquids of acoustic fields generated by ultrasonic medical equipment operating
in the frequency range up to 40 MHz.
The objectives of this standard are:
– to define a group of acoustic parameters that can be measured on a physically sound
basis;
– to define a second group of parameters that can be derived under certain assumptions
from these measurements, and called derived intensity parameters;
– to define a measurement procedure that may be used for the determination of acoustic
pressure parameters;
– to define the conditions under which the measurements of acoustic parameters can be
made in the frequency range up to 40 MHz using calibrated hydrophones;
– to define procedures for correcting, for limitations caused by the use of hydrophones with
finite bandwidth and finite active element size.
NOTE 1 Throughout this standard, SI units are used. In the specification of certain parameters, such as beam
areas and intensities, it may be convenient to use decimal multiples or submultiples. For example beam area may
2 2 2
be specified in cm and intensities in W/cm or mW/cm .
NOTE 2 The hydrophone as defined may be of a piezoelectric or an optic type. The introduction however implies
that optical hydrophones are not covered.
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 60050-801:1994, International Electrotechnical Vocabulary – Chapter 801: Acoustics and
electroacoustics
IEC 60565, Underwater acoustics – Hydrophones – Calibration in the frequency range 0,01 Hz
to 1 MHz
IEC/TR 60854:1986, Methods of measuring the performance of ultrasonic pulse-echo
diagnostic equipment
IEC 61689, Ultrasonics – Physiotherapy systems – Performance requirements and methods of
measurement in the frequency range 0,5 MHz to 5 MHz
IEC 61828, Ultrasonics – Focusing transducers – Definitions and measurement methods for
the transmitted fields
IEC 61846, Ultrasonics – Pressure pulse lithotripters – Characteristics of fields
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62127-1 © IEC:2007(E) – 9 –
IEC 61847, Ultrasonics – Surgical systems – Measurement and declaration of the basic output
characteristics
IEC 62127-2, Ultrasonics – Hydrophones – Part 2: Calibration for ultrasonic fields up to
40 MHz
IEC 62127-3, Ultrasonics – Hydrophones – Part 3: Properties of hydrophones for ultrasonic
fields up to 40 MHz
ISO 16269-6:2005, Statistical interpretation of data – Part 6: Determination of statistical
tolerance intervals
ISO, Guide to the expression of uncertainty in measurement. Geneva, Switzerland:
International Organization for Standardization (ISO), 1995
NOTE The following standards rely on the proper use of this document.
IEC 61157, Standard means for the reporting of the acoustic output of medical diagnostic ultrasonic equipment
IEC 62359, Ultrasonics – Field characterization – Test methods for the determination of thermal and mechanical
indices related to medical diagnostic ultrasonic fields
IEC 61847, Ultrasonics – Surgical systems – Measurement and declaration of the basic output characteristics.
3 Terms, definitions and symbols
For the purposes of this document, the terms and definitions given in IEC 62127-2, IEC 62127-
3 and the following apply. It also includes definitions related to subjects in this document to be
used in particular medical ultrasound device standards.
3.1
acoustic pulse waveform
temporal waveform of the instantaneous acoustic pressure at a specified position in an
acoustic field and displayed over a period sufficiently long to include all significant acoustic
information in a single pulse or tone-burst, or one or more cycles in a continuous wave
NOTE 1 Temporal waveform is a representation (e.g oscilloscope presentation or equation) of the instantaneous
acoustic pressure.
NOTE 2 Definition adopted from IEC 60469-1.
3.2
acoustic repetition period
arp
pulse repetition period for non-automatic scanning systems and the scan repetition period
for automatic scanning systems, equal to the time interval between corresponding points of
consecutive cycles for continuous wave systems
NOTE The acoustic repetition period is expressed in seconds (s).
3.3
acoustic frequency
acoustic-working frequency
frequency of an acoustic signal based on the observation of the output of a hydrophone
placed in an acoustic field at the position corresponding to the spatial-peak temporal-peak
acoustic pressure
NOTE 1 The signal is analysed using either the zero-crossing acoustic-working frequency technique or a
spectrum analysis method. Acoustic-working frequencies are defined in 3.3.1 and 3.3.2.
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– 10 – 62127-1 © IEC:2007(E)
NOTE 2 In a number of cases the present definition is not very helpful or convenient, especially for broadband
transducers. In that case, a full description of the frequency spectrum should be given in order to enable any
frequency-dependent correction to the signal.
NOTE 3 Acoustic frequency is expressed in hertz (Hz).
3.3.1
zero-crossing acoustic-working frequency
f
awf
this is determined according to the procedure specified in IEC/TR 60854
NOTE This frequency is intended for continuous wave systems only.
3.3.2
arithmetic-mean acoustic-working frequency
f
awf
arithmetic mean of the most widely separated frequencies f and f , within the range of three
1 2
times f , at which the magnitude of the acoustic pressure spectrum is 3 dB below the peak
1
magnitude
NOTE 1 This frequency is intended for pulse-wave systems only.
NOTE 2 It is assumed that f < f .
1 2
3.3.3
peak pulse acoustic frequency
f .
p
arithmetic-mean acoustic-working frequency of the pulse with the largest peak negative
acoustic pressure measured at the point of max
...
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