SIST EN 60793-1-60:2017

Optical fibres - Part 1-60: Measurement methods and test procedures - Beat length (IEC 60793-1-60:2017)

This part of IEC 60793 defines test methods for both the phase beat length, and the group
beat length. These two parameters are defined differently, and will give different results
depending on the type of polarization-maintaining (PM) fibre.
The phase beat length is the relevant parameter for the fibres ability to maintain a high
extinction ratio. This is described in more details in Annexes A and B.

Lichtwellenleiter - Teil 1-60: Messmethoden und Prüfverfahren - Schwebungslänge

Lichtwellenleiter - Teil 1-60: Messmethoden und Prüfverfahren - Schwebungslänge

Fibres optiques - Partie 1-60: Méthodes de mesure et procédures d’essai - Longueur de battement

IEC 60793-1-60:2017 définit des méthodes d’essai tant pour la longueur de battement de phase que pour la longueur de battement de groupe. Ces deux paramètres sont définis de manière différente et produisent des résultats différents selon le type de fibre à maintien de polarisation (PM – polarization-maintaining). La longueur de battement de phase est le paramètre approprié de la capacité des fibres à maintenir un rapport d’extinction élevé. Les Annexes A et B décrivent ces éléments de manière plus détaillée.

Optična vlakna - 1-60. del: Metode merjenja in preskusni postopki - Dolžina udarca (IEC 60793-1-60:2017)

Ta del standarda IEC 60793 opredeljuje preskusne metode za fazno in skupinsko dolžino udarca. Ta dva parametra sta opredeljena različno in bosta podala različne rezultate glede na vrsto vlakna, ki ohranja polarizacijo (PM).
Fazna dolžina udarca je pomemben parameter zmogljivosti vlaken za ohranjanje visoke hitrosti ugašanja. To je podrobneje opisano v dodatkih A in B.

General Information

• Status: Published
• Publication Date: 01-Jun-2017
• ICS: 33.180.10 - Fibres and cables
• Technical Committee: MOC - Mobile Communications
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 24-May-2017
• Due Date: 29-Jul-2017
• Completion Date: 02-Jun-2017
• Ref Project: EN 60793-1-60:2017 - Optical fibres - Part 1-60: Measurement methods and test procedures - Beat length

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN 60793-1-60:2017
01-julij-2017
2SWLþQDYODNQDGHO0HWRGHPHUMHQMDLQSUHVNXVQLSRVWRSNL'ROåLQDXGDUFD
,(&
Optical fibres - Part 1-60: Measurement methods and test procedures - Beat length (IEC
60793-1-60:2017)
Ta slovenski standard je istoveten z: EN 60793-1-60:2017
ICS:
33.180.10 2SWLþQDYODNQDLQNDEOL Fibres and cables
SIST EN 60793-1-60:2017 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN 60793-1-60:2017

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SIST EN 60793-1-60:2017


EUROPEAN STANDARD EN 60793-1-60

NORME EUROPÉENNE

EUROPÄISCHE NORM
May 2017
ICS 33.180.10

English Version
Optical fibres - Part 1-60: Measurement methods and test
procedures - Beat length
(IEC 60793-1-60:2017)
Fibres optiques - Partie 1-60: Méthodes de mesure et Lichtwellenleiter - Teil 1-60: Messmethoden und
procédures d'essai - Longueur de battement Prüfverfahren - Schwebungslänge
(IEC 60793-1-60:2017) (IEC 60793-1-60:2017)
This European Standard was approved by CENELEC on 2017-03-14. 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 CEN-CENELEC
Management Centre 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 CEN-CENELEC Management Centre has the
same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden,
Switzerland, Turkey and the United Kingdom.


European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2017 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
 Ref. No. EN 60793-1-60:2017 E

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SIST EN 60793-1-60:2017
EN 60793-1-60:2017
European foreword
The text of document 86A/1737/CDV, future edition 1 of IEC 60793-1-60, prepared by SC 86A "Fibres
and cables" of IEC/TC 86 "Fibre optics" was submitted to the IEC-CENELEC parallel vote and
approved by CENELEC as EN 60793-1-60:2017.
The following dates are fixed:
• latest date by which the document has to be implemented at (dop) 2017-12-14
national level by publication of an identical national
standard or by endorsement
• latest date by which the national standards conflicting with (dow) 2020-03-14
the document have to be withdrawn

Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC shall not be held responsible for identifying any or all such patent rights.
Endorsement notice
The text of the International Standard IEC 60793-1-60:2017 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 60793-2 NOTE Harmonized as EN 60793-2.
2

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SIST EN 60793-1-60:2017
EN 60793-1-60:2017
Annex ZA
(normative)

Normative references to international publications
with their corresponding European publications
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.
NOTE 1 When an International Publication has been modified by common modifications, indicated by (mod),
the relevant EN/HD applies.
NOTE 2 Up-to-date information on the latest versions of the European Standards listed in this annex is
available here: www.cenelec.eu.

Publication Year Title EN/HD Year
IEC 60068-1 -  Environmental testing - Part 1: General EN 60068-1 -
and guidance
IEC 60793-1-1 -  Optical fibres - Part 1-1: Measurement EN 60793-1-1 -
methods and test procedures - General
and guidance
IEC 60793-1-48 -  Optical fibres - Part 1-48: Measurement EN 60793-1-48 -
methods and test procedures -
Polarization mode dispersion
IEC 60793-2-70 -  Optical fibres - Part 2-70: Product EN 60793-2-70 -
specifications - Sectional specification
for polarization-maintaining fibres

3

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SIST EN 60793-1-60:2017

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SIST EN 60793-1-60:2017




IEC 60793-1-60

®


Edition 1.0 2017-02




INTERNATIONAL



STANDARD








colour

inside










Optical fibres –

Part 1-60: Measurement methods and test procedures – Beat length



























INTERNATIONAL

ELECTROTECHNICAL


COMMISSION





ICS 33.180.10 ISBN 978-2-8322-3865-3



  Warning! Make sure that you obtained this publication from an authorized distributor.


® Registered trademark of the International Electrotechnical Commission

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SIST EN 60793-1-60:2017
– 2 – IEC 60793-1-60:2017 © IEC 2017
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 Testing conditions . 6
5 Reference test method . 6
6 Specimen . 6
7 Test methods . 6
7.1 Phase beat length measurement methods . 6
7.1.1 General . 6
7.1.2 Monitoring of output power using an electromagnet . 6
7.1.3 Monitoring of SOP using a lateral force . 8
7.2 Group beat length measurement method . 10
7.2.1 General . 10
7.2.2 Apparatus and procedure. 10
7.2.3 Calculation . 11
8 Results . 11
8.1 Information available with each measurement . 11
8.2 Information available upon request . 12
Annex A (informative) Difference of beat lengths by measurement method (phase
beat length and group beat length) . 13
A.1 Phase modal birefringence and phase beat length . 13
A.2 Group modal birefringence and group beat length . 13
Annex B (informative) Correlation between results obtained by the two methods
(phase beat length and group beat length) . 16
B.1 General . 16
B.2 Example of correlation between phase and group beat lengths in the case of
PANDA fibres . 16
B.3 Example of correlation between phase and group beat lengths in the case of
elliptical core fibres . 17
Annex C (informative) Electromagnet for Faraday rotation . 18
Bibliography . 19

Figure 1 – Apparatus of phase beat length measurement using an electromagnet . 6
Figure 2 – Example of measurement profile by electromagnet . 8
Figure 3 – Set-up for measuring L when monitoring SOP together with a
B(phase)
moving lateral force . 9
Figure 4 – SOP measured at different levels of lateral force . 10
Figure 5 – Example of SOP evolution and normalized Stokes vector components . 10
Figure B.1 – Wavelength dependence of B /B [3] . 16
group phase
Figure C.1 – Schematic of the electromagnet . 18

Table B.1 – B /B of elliptical core fibres . 17
group phase

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SIST EN 60793-1-60:2017
IEC 60793-1-60:2017 © IEC 2017 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________

OPTICAL FIBRES –

Part 1-60: Measurement methods and test procedures –
Beat length

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 itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
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 60793-1-60 has been prepared by subcommittee 86A: Fibres and
cables, of IEC technical committee 86: Fibre optics.
The text of this International Standard is based on the following documents:
CDV Report on voting
86A/1737/CDV 86A/1782/RVC

Full information on the voting for the approval of this International Standard can be found in
the report on voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts in the IEC 60793 series, published under the general title Optical fibres, can
be found on the IEC website.

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SIST EN 60793-1-60:2017
– 4 – IEC 60793-1-60:2017 © IEC 2017
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
A bilingual version of this publication may be issued at a later date.

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 document using a
colour printer.

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SIST EN 60793-1-60:2017
IEC 60793-1-60:2017 © IEC 2017 – 5 –
OPTICAL FIBRES –

Part 1-60: Measurement methods and test procedures –
Beat length



1 Scope
This part of IEC 60793 defines test methods for both the phase beat length, and the group
beat length. These two parameters are defined differently, and will give different results
depending on the type of polarization-maintaining (PM) fibre.
The phase beat length is the relevant parameter for the fibres ability to maintain a high
extinction ratio. This is described in more details in Annexes A and B.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their
content constitutes requirements 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 60068-1, Environmental testing – Part 1: General and guidance
IEC 60793-1-1, Optical fibres – Part 1-1: Measurement methods and test procedures –
General and guidance
IEC 60793-1-48, Optical fibres – Part 1-48: Measurement methods and test procedures –
Polarization mode dispersion
1
IEC 60793-2-70 , Optical fibres – Part 2-70: Product specifications – Sectional specifications
for polarization-maintaining fibres
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60793-1-1 and the
following apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1
phase beat length
L
B(phase)
distance over which two orthogonal polarization modes are delayed by one cycle (2 )
p
3.2
group beat length
L
B(group)
distance over which the group delay difference is one cycle (2 )
p
Note 1 to entry A group delay is based on group refractive index.
___________
1
Under preparation. Stage at the time of publication: IEC CCDV 60793-2-70:2017.

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SIST EN 60793-1-60:2017
– 6 – IEC 60793-1-60:2017 © IEC 2017
4 Testing conditions
Unless otherwise specified, the test shall be conducted under the standard conditions
specified in IEC 60068-1. However, when it is difficult to make measurements in the standard
conditions, the test may be conducted in conditions other than the standard conditions
provided that no doubts will arise about judgments.
5 Reference test method
Since the phase beat length is the parameter specified in the product specification,
IEC 60793-2-70, both phase beat length test methods described in 7.1 are defined as the
reference test method (RTM). Test method for group beat length described in 7.2 can be used
as an alternative test method (ATM) when the correlation between phase and group beat
lengths is confirmed in advance (as shown in Annex B).
6 Specimen
A specimen length should be the minimum necessary to set up the test apparatus. If the
specimen is extra long, take care that no stresses will be induced in the specimen.
7 Test methods
7.1 Phase beat length measurement methods
7.1.1 General
The phase beat length measurement method is based on applying a point-like perturbation
along a short length of the fibre under test, and either monitor the changes in output power, or
monitor changes in output state of polarization (SOP) at one wavelength versus travel
distance.
The perturbation can either be a lateral force or an electromagnet.
In this document, the test methods where output power is monitored using an electromagnet,
and where SOP is monitored using a lateral force, are both described.
7.1.2 Monitoring of output power using an electromagnet
7.1.2.1 Apparatus
7.1.2.1.1 General apparatus
See Figure 1 for a diagram of the test set-up.
An ele
...