EN 60336:2005

SLOVENSKI SIST EN 60336:2006
STANDARD
januar 2006
Medicinska električna oprema – Rentgenske naprave za medicinsko
diagnostiko – Značilnosti žariščnih točk (IEC 60336:2005)
(istoveten EN 60336:2005)
Medical electrical equipment - X-ray tube assemblies for medical diagnosis -
Characteristics of focal spots (IEC 60336:2005)
ICS 11.040.50; 11.040.55 Referenčna številka
©  Standard je založil in izdal Slovenski inštitut za standardizacijo. Razmnoževanje ali kopiranje celote ali delov tega dokumenta ni dovoljeno

EUROPEAN STANDARD EN 60336
NORME EUROPÉENNE
EUROPÄISCHE NORM July 2005
ICS 11.040.50 Supersedes EN 60336:1995

English version
Medical electrical equipment –
X-ray tube assemblies for medical diagnosis –
Characteristics of focal spots
(IEC 60336:2005)
Appareils électromédicaux –  Medizinische elektrische Geräte -
Gaines équipées pour diagnostic médical - Röntgenstrahler für medizinische
Caractéristiques des foyers Diagnostik –
(CEI 60336:2005) Kennwerte von Brennflecken
(IEC 60336:2005)
This European Standard was approved by CENELEC on 2005-06-01. 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, Cyprus, Czech
Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden,
Switzerland and 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

© 2005 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.

Ref. No. EN 60336:2005 E
Foreword
The text of document 62B/554/FDIS, future edition 4 of IEC 60336, 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 60336 on 2005-06-01.
This European Standard supersedes EN 60336:1995.
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) 2006-03-01
– latest date by which the national standards conflicting
with the EN have to be withdrawn (dow) 2008-06-01
Annex ZA has been added by CENELEC.
__________
Endorsement notice
The text of the International Standard IEC 60336:2005 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 60601-2-28 NOTE Harmonized as EN 60601-2-28:1993 (not modified).
__________
- 3 - EN 60336:2005
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 Where an international publication has been modified by common modifications, indicated by (mod), the relevant
EN/HD applies.
Publication Year Title EN/HD Year
IEC 60417 database Graphical symbols for use on - -
equipment
1) 2)
IEC 60613 - Electrical, thermal and loading EN 60613 1990
characteristics of rotating anode X-ray
tubes for medical diagnosis
IEC/TR 60788 2004 Medical electrical equipment - - -
Glossary of defined terms
1)
Undated reference.
2)
Valid edition at date of issue.

NORME CEI
INTERNATIONALE
IEC
INTERNATIONAL
Quatrième édition
STANDARD
Fourth edition
2005-04
Appareils électromédicaux –
Gaines équipées pour diagnostic médical –
Caractéristiques des foyers
Medical electrical equipment –
X-ray tube assemblies for medical diagnosis –
Characteristics of focal spots

 IEC 2005 Droits de reproduction réservés  Copyright - all rights reserved
Aucune partie de cette publication ne peut être reproduite ni No part of this publication may be reproduced or utilized in any
utilisée sous quelque forme que ce soit et par aucun procédé, form or by any means, electronic or mechanical, including
électronique ou mécanique, y compris la photocopie et les photocopying and microfilm, without permission in writing from
microfilms, sans l'accord écrit de l'éditeur. the publisher.
International Electrotechnical Commission, 3, rue de Varembé, PO Box 131, CH-1211 Geneva 20, Switzerland
Telephone: +41 22 919 02 11 Telefax: +41 22 919 03 00 E-mail: inmail@iec.ch Web: www.iec.ch
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International Electrotechnical Commission
МеждународнаяЭлектротехническаяКомиссия
Pour prix, voir catalogue en vigueur
For price, see current catalogue

60336  IEC:2005 – 3 –
CONTENTS
FOREWORD.7

1 Scope.11
2 Normative references .11
3 Terms and definitions .11
4 Determinations for the evaluation of the FOCAL SPOT characteristics.11
4.1 Statement of the FOCAL SPOT characteristics .11
4.2 Longitudinal axis of the X-RAY TUBE ASSEMBLY.11
4.3 REFERENCE AXIS of the X-RAY TUBE ASSEMBLY .13
4.4 Direction of evaluation for the FOCAL SPOT length.13
4.5 Direction of evaluation for the FOCAL SPOT width .13
5 FOCAL SPOT camera set-up .13
5.1 Overview .13
5.2 Test equipment .13
5.3 Test arrangement .17
5.4 Total uncertainty of the camera set-up .23
6 Production of RADIOGRAMS .23
6.1 Overview .23
6.2 Operating conditions .23
6.3 Production of FOCAL SPOT SLIT RADIOGRAMS or FOCAL SPOT PINHOLE
RADIOGRAMS.25
6.4 Statement of compliance .27
7 Determination of the LINE SPREAD FUNCTION.27
7.1 Overview .27
7.2 Measuring equipment and measuring arrangement.27
7.3 Measurement of the density distribution .29
7.4 Determination of the LINE SPREAD FUNCTION .29
7.5 Statement of compliance .29
8 Determination of FOCAL SPOT dimensions.31
8.1 Overview .31
8.2 Measurement and determination .31
8.3 Specified NOMINAL FOCAL SPOT VALUES .33
8.4 Statement of compliance .37
8.5 Marking of compliance.37
9 Determination of the MODULATION TRANSFER FUNCTION .37
9.1 Overview .37
9.2 Specified MODULATION TRANSFER FUNCTION.37
9.3 Calculation of the MODULATION TRANSFER FUNCTION .39
9.4 Evaluation of compliance of the MTF.41
9.5 Statement of compliance .41
10 FOCAL SPOT STAR RADIOGRAMS.41
10.1 Overview .41
10.2 Test equipment .43
11 STAR PATTERN RESOLUTION LIMIT .47
11.1 Overview .47

60336  IEC:2005 – 5 –
11.2 Specified STAR PATTERN RESOLUTION LIMIT .47
11.3 Measurement .49
11.4 Determination of the STAR PATTERN RESOLUTION LIMIT .49
11.5 Evaluation and statement of compliance.51
12 BLOOMING VALUE.53
12.1 Overview .53
12.2 Determination of the BLOOMING VALUE .53
12.3 Evaluation and statement of compliance.53
13 Alternate measurement methods .55

Annex A (informative) Alignment to the REFERENCE AXIS.57
Annex B (informative) Application of digital X-ray image detectors for determination of
the FOCAL SPOT characteristics .61
Annex C (informative) Historical background.63

Bibliography.73
Index of defined terms .75

Figure 1 – Essential dimensions of the slit diaphragm.15
Figure 2 – Essential dimensions of the pinhole diaphragm .17
Figure 3 − Position of the centre of the slit or pinhole diaphragm (marked as x in the
figure) with respect to the REFERENCE AXIS .19
Figure 4 – Reference dimensions and planes.21
Figure 5 − Alignment of the optical densitometer slit .29
Figure 6 – LINE SPREAD FUNCTION.31
Figure 7 – Essential dimensions of the star test pattern .43
Figure 8 – Essential dimensions of the star test pattern .45
Figure 9 – Illustration of the zones of minimum modulation .49
Figure A.1 – The REFERENCE AXIS and directions of evaluation .57
Figure A.2 – Projection of the ACTUAL FOCAL SPOT on the IMAGE RECEPTION PLANE.59
Figure C.1 – The LSFs for a typical X-RAY TUBE with small FOCAL SPOT (< 0,3 mm) .65
Figure C.2 – The LSFs for a typical X-RAY TUBE with large FOCAL SPOT (≥0,3 mm).65
Figure C.3 – The corresponding MTFs for the LSFs in Figure C.2 .67

Table 1 – Enlargement for FOCAL SPOT RADIOGRAMs .23
Table
...