prEN IEC 62127-3:2022
(Main)Ultrasonics - Hydrophones - Part 3: Properties of hydrophones for ultrasonic fields
Ultrasonics - Hydrophones - Part 3: Properties of hydrophones for ultrasonic fields
Ultraschall - Hydrophone - Teil 3: Eigenschaften von Hydrophonen zur Verwendung in Ultraschallfeldern
Ultrasons - Hydrophones - Partie 3: Propriétés des hydrophones pour les champs ultrasoniques
Ultrazvok - Hidrofoni - 3. del: Lastnosti hidrofonov za ultrazvočna polja
General Information
RELATIONS
Standards Content (sample)
SLOVENSKI STANDARD
oSIST prEN IEC 62127-3:2022
01-maj-2022
Ultrazvok - Hidrofoni - 3. del: Lastnosti hidrofonov za ultrazvočna polja
Ultrasonics - Hydrophones - Part 3: Properties of hydrophones for ultrasonic fields
Ultraschall - Hydrophone - Teil 3: Eigenschaften von Hydrophonen zur Verwendung in
UltraschallfeldernUltrasons - Hydrophoes - Partie 3: Propriétés des hydrophones pour les champs
ultrasoniques jusqu'à 40 MHz
Ta slovenski standard je istoveten z: prEN IEC 62127-3:2022
ICS:
11.040.01 Medicinska oprema na Medical equipment in general
splošno
17.140.50 Elektroakustika Electroacoustics
oSIST prEN IEC 62127-3:2022 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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oSIST prEN IEC 62127-3:2022
87/786/CDV
COMMITTEE DRAFT FOR VOTE (CDV)
PROJECT NUMBER:
IEC 62127-3 ED2
DATE OF CIRCULATION: CLOSING DATE FOR VOTING:
2022-02-25 2022-05-20
SUPERSEDES DOCUMENTS:
87/751/CD, 87/782/CC
IEC TC 87 : ULTRASONICS
SECRETARIAT: SECRETARY:
United Kingdom Mr Petar Luzajic
OF INTEREST TO THE FOLLOWING COMMITTEES: PROPOSED HORIZONTAL STANDARD:
Other TC/SCs are requested to indicate their interest, if any, in
this CDV to the secretary.
FUNCTIONS CONCERNED:
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SUBMITTED FOR CENELEC PARALLEL VOTING NOT SUBMITTED FOR CENELEC PARALLEL VOTING
Attention IEC-CENELEC parallel votingThe attention of IEC National Committees, members of
CENELEC, is drawn to the fact that this Committee Draft
for Vote (CDV) is submitted for parallel voting.
The CENELEC members are invited to vote through the
CENELEC online voting system.
This document is still under study and subject to change. It should not be used for reference purposes.
Recipients of this document are invited to submit, with their comments, notification of any relevant patent rights of which they
are aware and to provide supporting documentation.TITLE:
Ultrasonics - Hydrophones - Part 3: Properties of hydrophones for ultrasonic fields
PROPOSED STABILITY DATE: 2025NOTE FROM TC/SC OFFICERS:
Copyright © 2022 International Electrotechnical Commission, IEC. All rights reserved. It is permitted to download this
electronic file, to make a copy and to print out the content for the sole purpose of preparing National Committee positions.
You may not copy or "mirror" the file or printed version of the document, or any part of it, for any other purpose without
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1 CONTENTS
2 1 Scope ............................................................................................................................... 7
3 2 Normative references ....................................................................................................... 7
4 3 Terms, definitions and symbols ........................................................................................ 7
5 4 List of symbols ............................................................................................................... 10
6 5 Hydrophone characteristics ............................................................................................ 11
7 5.1 General ................................................................................................................. 11
8 5.2 Basic information ................................................................................................... 11
9 5.3 Sensitivity ............................................................................................................. 11
10 5.4 Frequency response .............................................................................................. 12
11 5.4.1 Stated frequency band ............................................................................... 12
12 5.4.2 Frequency dependence ............................................................................. 12
13 5.5 Directional response .............................................................................................. 13
14 5.5.1 General ..................................................................................................... 13
15 5.5.2 Determination of the direction response ..................................................... 13
16 5.5.3 Symmetry of directional response .............................................................. 14
17 5.6 Effective hydrophone size ..................................................................................... 14
18 5.6.1 General ..................................................................................................... 14
19 5.6.2 Model of directional response .................................................................... 14
20 5.6.3 Fitting of experimental response to theoretical predictions ......................... 15
21 5.7 Dynamic range, linearity and electromagnetic interference .................................... 16
22 5.8 Electric output characteristics ................................................................................ 16
23 5.8.1 Hydrophone without pre-amplifier .............................................................. 16
24 5.8.2 Hydrophone assembly ............................................................................... 17
25 5.8.3 Output lead configuration .......................................................................... 17
26 5.9 Environmental aspects .......................................................................................... 17
27 5.9.1 Temperature range .................................................................................... 17
28 5.9.2 Water tightness ......................................................................................... 17
29 5.9.3 Water properties and incompatible materials ............................................. 17
30 5.9.4 Exposed material ....................................................................................... 18
31 5.10 Guidance manual .................................................................................................. 18
32 5.11 List of hydrophone characteristics ......................................................................... 18
33 Annex A (informative) Examples of information on hydrophone properties ........................... 19
34 A.1 General ................................................................................................................. 19
35 A.2 Basic information ................................................................................................... 19
36 A.3 Sensitivity and frequency response ....................................................................... 19
37 A.4 Directional response .............................................................................................. 22
38 A.5 Effective dimension ............................................................................................... 23
39 A.6 Dynamic range, linearity and electromagnetic interference .................................... 24
40 A.6.1 Lower dynamic limit ................................................................................... 24
41 A.6.2 Upper dynamic limit ................................................................................... 24
42 A.7 Electric output characteristics ................................................................................ 24
43 A.8 Environmental aspects .......................................................................................... 24
44 Annex B (informative) Rationale........................................................................................... 26
45 B.1 General ................................................................................................................. 26
46 B.2 Changes to the determination of directional response ........................................... 26
47 B.3 Changes to the determination of effective radius ................................................... 26
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48 Annex C (informative) Membrane hydrophone directivity model ........................................... 28
49 C.1 General ................................................................................................................. 28
50 C.2 Details of model .................................................................................................... 28
52 Figure A.1 – Frequency response of 0,2 mm needle hydrophone .......................................... 20
53 Figure A.2 – Directional response of 0,2 mm needle hydrophone .......................................... 22
55 Table A.1 – Example of basic information for 0,2 mm needle hydrophone assembly ............. 19
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58 INTERNATIONAL ELECTROTECHNICAL COMMISSION
59 ____________
61 ULTRASONICS – HYDROPHONES –
63 Part 3: Properties of hydrophones for ultrasonic fields
65 FOREWORD
66 1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
67 all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
68 international co-operation on all questions concerning standardization in the electrical and electronic fields. To
69 this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
70 Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
71 Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
72 in the subject dealt with may participate in this preparatory work. International, governmental and non-
73 governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely
74 with the International Organization for Standardization (ISO) in accordance with conditions determined by
75 agreement between the two organizations.76 2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
77 consensus of opinion on the relevant subjects since each technical committee has representation from all
78 interested IEC National Committees.79 3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
80 Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
81 Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
82 misinterpretation by any end user.83 4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
84 transparently to the maximum extent possible in their national and regional publications. Any divergence
85 between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
86 the latter.87 5) IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
88 equipment declared to be in conformity with an IEC Publication.89 6) All users should ensure that they have the latest edition of this publication.
90 7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
91 members of its technical committees and IEC National Committees for any personal injury, property damage or
92 other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
93 expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
94 Publications.95 8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
96 indispensable for the correct application of this publication.97 9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
98 patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
99 This second edition cancels and replaces the first edition published in 2007-08 and its
100 amendment 1 (2013-05). This edition constitutes a technical revision.101 This edition includes the following significant technical changes with respect to the previous
102 edition:103 a) The upper frequency limit of 40 MHz has been removed;
104 b) Hydrophone sensitivity definitions have been changed to recognize sensitivities as
105 complex-valued quantities;106 c) Procedures to determine the effective hydrophone size have been changed according to
107 the rationale outlined in Annex B;108 d) Requirements on the frequencies for which the effective hydrophone size shall be
109 provided have been changed to achieve practicality for increased frequency bands;
110 e) The new Annexes B and C have been added;111 f) Annex A has been updated to reflect the changes of the normative parts.
112
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113 International Standard IEC 62127-3 has been prepared by IEC technical committee 87:
114 Ultrasonics.115 This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
116 A list of all parts of IEC 62127 series, published under the general title Ultrasonics –
117 Hydrophones, can be found on the IEC website.118 NOTE Words in bold in the text are defined in Clause 3.
119 The committee has decided that the contents of the base publication and its amendment will
120 remain unchanged until the maintenance result date indicated on the IEC website under
121 "http://webstore.iec.ch" in the data related to the specific publication. At this date, the
122 publication will be123 • reconfirmed,
124 • withdrawn,
125 • replaced by a revised edition, or
126 • amended.
127
IMPORTANT – The “colour inside” logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct understanding
of its contents. Users should therefore print this publication using a colour printer.
128129
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130 INTRODUCTION
131 The spatial and temporal distribution of acoustic pressure in an ultrasonic field in a liquid
132 medium is commonly determined using miniature ultrasonic hydrophones. The properties of
133 these hydrophones have been dealt with in a number of IEC standards in various aspects.
134 The purpose of this part of IEC 62127 is to bring together all these specifications and to
135 establish a common standard on the properties of ultrasonic hydrophones. The main
136 hydrophone application in this context is the measurement of ultrasonic fields emitted by
137 medical diagnostic equipment in water. Other medical applications are field measurements for
138 therapy equipment such as that used in lithotripsy, high-intensity focused ultrasound (HIFU)
139 and physiotherapy. Hydrophones are also used extensively in non-medical applications for
140 both product development and quality control including:141 – mapping of the ultrasound field within ultrasonic cleaning baths;
142 – characterization of acoustic fields used in transmission measurement systems (e.g.
143 ultrasonic spectrometers, ultrasonic attenuation meters and velocimeters);144 – characterization of acoustic fields used in reflection measurement systems (e.g. Doppler
145 flowmeters).146 While the term "hydrophone" can be used in a wider sense, it is understood here as referring
147 to miniature piezoelectric hydrophones. It is this instrument type that is used today in various
148 areas of ultrasonics and, in particular, to quantitatively characterize the field structure of
149 medical diagnostic instruments. With regard to other pressure sensor types, such as those
150 based on fibre optics, some of the requirements of this standard are applicable to these as
151 well but others are not. If in the future these other "hydrophone" types gain more importance
152 in field measurement practice, their properties will have to be dealt with in a revised version of
153 this document or in a separate one.154 Underwater hydrophones as covered by IEC 60500, IEC 60565-1, and IEC 60565-2 are not
155 included in this document, although there is an overlap in the frequency ranges. Underwater
156 hydrophones are used in natural waters, even in the ocean, and this leads to different
157 technical concepts and requirements. In addition, the main direction of acoustic incidence in
158 underwater applications is at various angles and often at right angles to the hydrophone
159 axis, whereas this standard it is assumed that the main direction of acoustic incidence is in
160 the direction of the hydrophone axis.161 Historically, ultrasonic hydrophones were used almost exclusively as amplitude sensors.
162 However, the complex-valued nature of a hydrophone’s system response function is well
163 understood and IEC 62127-1 Ed 2 makes use of this within the deconvolution procedures it
164 contains. In this document, requirements are specified for the amplitude aspect of the
165 hydrophone sensitivity and recommendations are provided for the phase aspect which can
166 be derived either via calibration, or via calculation methods that are discussed in IEC 62127-1
167 Ed 2.168
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169 ULTRASONICS – HYDROPHONES –
170
171 Part 3: Properties of hydrophones for ultrasonic fields
172
173 1 Scope
174 This part of IEC 62127 specifies relevant hydrophone characteristics.
175 This standard is applicable to:
176 – hydrophones employing piezoelectric sensor elements, designed to measure the pulsed
177 and continuous wave ultrasonic fields generated by ultrasonic equipment;178 – hydrophones used for measurements made in water;
179 – hydrophones with or without an associated pre-amplifier.
180 2 Normative references
181 The following referenced documents are indispensable for the application of this document.
182 For dated references, only the edition cited applies. For undated references, the latest edition
183 of the referenced document (including any amendments) applies.184 IEC 62127-1, Ultrasonics – Hydrophones – Part 1: Measurement and characterization of
185 medical ultrasonic fields up to 40 MHz186 IEC 62127-2, Ultrasonics – Hydrophones – Part 2: Calibration for ultrasonic fields up to
187 40 MHz188 3 Terms, definitions and symbols
189 For the purposes of this document, the terms and definitions given in IEC 62127-1,
190 IEC 62127-2 and the following apply.191 ISO and IEC maintain terminological databases for use in standardization at the following
192 addresses:193 • IEC Electropedia: available at http://www.electropedia.org/
194 • ISO Online browsing platform: available at http://www.iso.org/obp
195 3.1
196 acoustic pulse waveform
197 temporal waveform of the instantaneous acoustic pressure at a specified position in an
198 acoustic field and displayed over a period sufficiently long to include all significant acoustic
199 information in a single pulse or tone-burst, or one or more cycles in a continuous wave
200 Note 1 to entry: Temporal waveform is a representation (e.g. oscilloscope presentation or formula) of the
201 instantaneous acoustic pressure.202 [SOURCE: IEC 62127-1:2007 and Amendment 1:2013, definition 3.1]
203 3.2
204 directional response
205 description of the response of a hydrophone, as a function of direction of propagation of the
206 incident plane sound wave, in a specified plane through the reference centre and at a
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208 NOTE 1 Definition adopted from IEC 60565:2006.
209 NOTE 2 Whilst directional response is a complex-valued function, it is generally the magnitude of directional
210 response that is of most interest and this commonly presented graphically.211 3.3
212 effective hydrophone size
213 a
214 size of a theoretical receiver hydrophone that has a predicted directional response function
215 with an angular width equal to the observed angular width216 NOTE 1 The size is usually the function of frequency. For representative experimental data, see [1].
217 NOTE 2 The effective hydrophone size is expressed in metres (m).218 NOTE 3 For hydrophones with a circular geometry, the effective hydrophone size is a radius.
219 NOTE 4 For hydrophones with a rectangular geometry, the effective hydrophone size is the half the greatest
220 value of the length or width.221 3.4
222 electric load impedance
223 Z
224 complex electric input impedance (consisting of a real and an imaginary part) to wh ich the
225 hydrophone or hydrophone assembly output is connected or is to be connected226 NOTE The electric load impedance is expressed in ohms ().
227 3.5
228 end-of-cable
229 specification that relates to the end of the integral output cable if the hydrophone or
230 hydrophone assembly is provided with such a cable and if the hydrophone or hydrophone
231 assembly is not provided with an integral output cable, the specification relates to the output
232 connector firmly connected with the hydrophone or hydrophone assembly, not to an extra
233 cable234 3.6
235 end-of-cable loaded sensitivity
236 M (f)
237 quotient of the Fourier transformed
238 hydrophone voltage-time signal (u (t)) at the end of any integral cable or output connector
239 of a hydrophone or hydrophone-assembly, when connected to a specified electric load
240 impedance, to the Fourier transformed acoustic pulse waveform (p(t)) in the undisturbed
241 free field of a plane wave in the position of the reference centre of the hydrophone if the
242 hydrophone were removed( ( ))
243 Mf = (1)
( )
( ( ))
244 Note 1 to entry: The end-of-cable loaded sensitivity is a complex-valued parameter. Its modulus is expressed
245 in units of volt per pascal (V/Pa), its phase angle is expressed in degrees, and represents the phase difference
246 between the electrical voltage and the sound pressure.247 3.7
248 end-of-cable open-circuit sensitivity
249 M (f)
250 quotient of the Fourier transformed hydrophone open-circuit voltage-
251 time signal (u (t)) at the end of any integral cable or output connector of a hydrophone to
252 the Fourier transformed acoustic pulse waveform (p(t)) in the undisturbed free field of a
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253 plane wave in the position of the reference centre of the hydrophone if the hydrophone
254 were removed( ( ))
255 Mf( )= (2)
( ( ))
256 Note 1 to entry: The end-of-cable open-circuit sensitivity is a complex-valued parameter. Its modulus is
257 expressed in units of volt per pascal (V/Pa), its phase angle is expressed in degrees, and represents the phase
258 difference between the electrical voltage and the sound pressure.259 3.8
260 end-of-cable loaded sensitivity level
( )
261
262 twenty times the logarithm to the base 10 of
263 the quotient of the modulus of the end-of-cable loaded sensitivity |M (f)| to a reference
264 sensitivity Mref
( )
265 Lf( )= 20log dB (3)
M 10
ref
266 Note 1 to entry: Commonly used values of the reference sensitivity M are 1V/µPa or 1V/Pa.
ref267 Note 2 to entry: The end-of-cable loaded sensitivity level is expressed in decibels (dB).
268 3.9269 free field
270 sound field in a homogeneous and isotropic medium in which the effects of boundaries are
271 negligible272 Note 1 to entry: Definition adopted from IEC 60565:2006, 3.13.
273 3.10
274 hydrophone geometrical size
275 geometrical size of a hydrophone active element
276 a
277 size defined by the lateral extents of the active element of a hydrophone
278 Note 1 to entry: The hydrophone geometrical size is expressed in metres (m).
279 Note 2 to entry: For hydrophones with a circular geometry, the hydrophone geometrical size is a radius.
280 Note 3 to entry: For hydrophones with a rectangular geometry, the hydrophone geometrical size is a half the
281 greatest value of the length or width.282 3.11
283 hydrophone
284 transducer that produces electric signals in response to waterborne acoustic signals
285 SOURCE: IEV 801-32-26286 3.12
287 hydrophone assembly
288 combination of hydrophone and hydrophone pre-amplifier
289 3.13
290 hydrophone axis
291 nominal symmetry axis of the hydrophone active element
292 Note 1 to entry: Unless stated otherwise (explicitly and quantitatively) by the manufacturer, it is understood for
293 the purposes of this standard that this is given by the apparent geometrical symmetry axis of the hydrophone.
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294 3.14
295 hydrophone pre-amplifier
296 active electronic device connected to, or to be connected to, a particular hydrophone and
297 reducing its output impedance298 Note 1 to entry: A hydrophone pre-amplifier requires a supply voltage (or supply voltages).
299 Note 2 to entry: The hydrophone pre-amplifier may have a forward voltage transmission factor of less than one,
300 i.e. it need not necessarily be a voltage amplifier in the strict sense.301 3.15
302 reference centre
303 point on or near a hydrophone about which its acoustic receiving sensitivity is defined
304 Note 1 to entry: Unless stated otherwise (explicitly and quantitatively) by the manufacturer, it is understood for
305 the purposes of this standard that this is given by the geometrical centre of the front surface of the hydrophone
306 active element.307 Note 2 to entry: Definition adopted from IEC 60565:2006, 3.25.
308 3.16
309 uncertainty
310 parameter, associated with the result of a measurement, that characterizes the dispersion of
311 the values that could reasonably be attributed to the measurand312 Note 1 to entry: See the ISO Guide to the Expression of Uncertainty in Measurement [2], 2.2.3
313 Note 2 to entry: Definition adopted from IEC 62127-1.314
315
316 4 List of symbols
317 a hydrophone geometrical size
318 a effective hydrophone size
319 c speed of sound in a medium
320 D model function used during the determination of effective hydrophone size from
321 a measured directional response of a hydrophone322 f frequency
323 k wavenumber = 2π / λ
( )
L end-of-cable loaded sensitivity level
324
325 M general symbol for the complex hydrophone sensitivity, M =M being its
326 modulus and arg(M) being its argument (= phase angle)
327 M end-of-cable open-circuit sensitivity
328 M end-of-cable loaded sensitivity
329 Z complex electric output impedance of a hydrophone or hydrophone assembly
330 Z electric load impedance
331 angle of incidence of an ultrasonic wave with respect to the hydrophone axis
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333 5 Hydrophone characteristics
334 5.1 General
335 For a full characterization of the hydrophone performance in the frequency range of this
336 standard, the following information is required. Examples of information on hydrophone
337 characteristics are provided in Annex A.338 NOTE Determination methods are covered in IEC 62127-2.
339 5.2 Basic information
340 The following shall be briefly stated:
341 – the basic physical principles of the transduction process, the type of sensor material
342 involved, the form and geometrical dimensions (diameter, thickness) of the hydrophone
343 active element and the needle diameter in case of a needle hydrophone;344 – the configuration and design of the hydrophone;
345 – whether or not a pre-amplifier is associated with the hydrophone; if the pre-amplifier can
346 be disconnected from the hydrophone, clear information shall be given as to which pre-
347 amplifier type belongs to which hydrophone type;348 – the nominal direction of ultrasonic incidence in relation to the hydrophone.
349 NOTE The last point is important, as it has been found in the literature [ 3] that even with membrane
350 hydrophones, the response might change upon reversal of the ultrasonic propagation direction in relation to the
351 hydrophone.352 The following should be briefly stated:
353 – the lateral and thickness dimensions of the hydrophone active element;
354 – the frequency of the fundamental thickness resonance of the hydrophone active element;
355 – the size and weight of the hydrophone;356 – the recommended directional response model (see clause 5.6.2) appropriate for the
357 hydrophone;358 – in the case of a membrane hy
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