SIST EN 60793-1-20:2015

Optical fibres -- Part 1-20: Measurement methods and test procedures - Fibre geometry (IEC 60793-1-20:2014)

This part of IEC 60793 establishes uniform requirements for measuring the geometrical
characteristics of uncoated optical fibres.
The geometry of uncoated optical fibres directly affect splicing, connectorization and cabling
and so are fundamental parameters requiring careful specification, quality control, and thus
measurement.

Lichtwellenleiter - Teil 1-20: Messmethoden und Prüfverfahren - Fasergeometrie (IEC 60793-1-20:2014)

Fibres optiques -- Partie 1-20: Méthodes de mesure et procédures d'essai - Géométrie de la fibre (IEC 60793-1-20:2014)

L'IEC 60793-1-20:2014 établit des exigences uniformes pour mesurer les caractéristiques géométriques des fibres optiques nues. La géométrie des fibres optiques nues affecte directement l'épissurage, le montage des connecteurs (connectorisation) et le câblage et est donc un paramètre fondamental nécessitant une spécification minutieuse, un contrôle qualité et par la même, des mesures. Cette deuxième édition annule et remplace la première édition, publiée en 2001, dont elle constitue une révision technique. Cette édition contient les modifications techniques principales suivantes par rapport à l'édition précédente:
- la méthode d'essai de référence pour tous les types de fibres est modifiée de la méthode du champ proche réfracté à la méthode du champ proche transmis sur vidéo en niveaux de gris;
- les longueurs d'essai de tous les types de fibres doivent désormais être spécifiées dans la spécification particulière de la fibre;
- bien que des valeurs par défaut soient données, la longueur d'onde d'illumination du coeur pour tous les types de fibres multimodales peut désormais être spécifiée dans la spécification particulière de la fibre;
- le facteur k appliqué sur le coeur (niveau de décision) doit maintenant être spécifié dans la spécification particulière pour tous les types de fibres multimodales;
- la présente édition décrit le mesurage de manière bien plus spécifique;
- la réduction et la transformation des données sont décrites de manière exhaustive;
- la méthodologie de réduction des données pour la méthode du champ proche réfracté et pour la méthode du champ proche transmis est maintenant unifiée et cohérente.
Mots clés: mesurer les caractéristiques géométriques des fibres optiques nues

Optična vlakna - 1-20. del: Metode merjenja in preskusni postopki - Geometrija vlakna (IEC 60793-1-20:2014)

Ta del standarda IEC 60793 uvaja enotne zahteve za merjenje geometrijskih lastnosti neprevlečenih optičnih vlaken.
Geometrija neprevlečenih optičnih vlaken neposredno vpliva na spajanje, konektorizacijo in okablenje; gre za temeljne parametre, ki zahtevajo natančno določitev, nadzor kakovosti in merjenje.

General Information

• Status: Published
• Publication Date: 10-Jun-2015
• ICS: 33.180.10 - Fibres and cables
• Technical Committee: MOC - Mobile Communications
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 08-Dec-2014
• Due Date: 12-Feb-2015
• Completion Date: 11-Jun-2015
• Ref Project: EN 60793-1-20:2014 - Optical fibres - Part 1-20: Measurement methods and test procedures - Fibre geometry

Relations

• Replaces: SIST EN 60793-1-20:2004 - Optical fibres -- Part 1-20: Measurement methods and test procedures - Fibre geometry
• Effective Date: 28-Jan-2023
• Corrected By: SIST EN 60793-1-20:2015/AC:2016 - Optical fibres - Part 1-20: Measurement methods and test procedures - Fibre geometry
• Effective Date: 15-Mar-2016

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN 60793-1-20:2015
01-julij-2015
1DGRPHãþD
SIST EN 60793-1-20:2004
2SWLþQDYODNQDGHO0HWRGHPHUMHQMDLQSUHVNXVQLSRVWRSNL*HRPHWULMD
YODNQD,(&
Optical fibres -- Part 1-20: Measurement methods and test procedures - Fibre geometry
(IEC 60793-1-20:2014)
Lichtwellenleiter - Teil 1-20: Messmethoden und Prüfverfahren - Fasergeometrie (IEC
60793-1-20:2014)
Fibres optiques -- Partie 1-20: Méthodes de mesure et procédures d'essai - Géométrie
de la fibre (IEC 60793-1-20:2014)
Ta slovenski standard je istoveten z: EN 60793-1-20:2014
ICS:
33.180.10 2SWLþQDYODNQDLQNDEOL Fibres and cables
SIST EN 60793-1-20:2015 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN 60793-1-20:2015

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SIST EN 60793-1-20:2015


EUROPEAN STANDARD EN 60793-1-20

NORME EUROPÉENNE

EUROPÄISCHE NORM
November 2014
ICS 33.180.10 Supersedes EN 60793-1-20:2002
English Version
Optical fibres - Part 1-20: Measurement methods and test
procedures - Fibre geometry
(IEC 60793-1-20:2014)
Fibres optiques - Partie 1-20: Méthodes de mesure et Lichtwellenleiter - Teil 1-20: Messmethoden und
procédures d'essai - Géométrie de la fibre Prüfverfahren - Fasergeometrie
(CEI 60793-1-20:2014) (IEC 60793-1-20:2014)
This European Standard was approved by CENELEC on 2014-11-14. 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, 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
© 2014 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
 Ref. No. EN 60793-1-20:2014 E

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SIST EN 60793-1-20:2015
EN 60793-1-20:2014 - 2 -
Foreword
The text of document 86A/1562/CDV, future edition 1 of IEC 60793-1-20, 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 60793-1-20:2014.
The following dates are fixed:
(dop) 2015-08-14
• latest date by which the document has to be implemented at
national level by publication of an identical national
standard or by endorsement
(dow) 2017-11-14
• latest date by which the national standards conflicting with
the document have to be withdrawn

This document supersedes EN 60793-1-20:2002.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC [and/or CEN] shall not be held responsible for identifying any or all such
patent rights.
Endorsement notice
The text of the International Standard IEC 60793-1-20:2014 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 60793-1-45 NOTE Harmonized as EN 60793-1-45.

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SIST EN 60793-1-20:2015
- 3 - EN 60793-1-20:2014
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 60793-2-10 -  Optical fibres - EN 60793-2-10 -
Part 2-10: Product specifications -
Sectional specification for category A1
multimode fibres
IEC 60793-2-20 -  Optical fibres - EN 60793-2-20 -
Part 2-20: Product specifications -
Sectional specification for category A2
multimode fibres
IEC 60793-2-30 -  Optical fibres - EN 60793-2-30 -
Part 2-30: Product specifications -
Sectional specification for category A3
multimode fibres
IEC 60793-2-40 -  Optical fibres - EN 60793-2-40 -
Part 2-40: Product specifications -
Sectional specification for category A4
multimode fibres
IEC 60793-2-50 -  Optical fibres - EN 60793-2-50 -
Part 2-50: Product specifications -
Sectional specification for class B single-
mode fibres
IEC 60793-2-60 -  Optical fibres - EN 60793-2-60 -
Part 2-60: Product specifications -
Sectional specification for category C
single-mode intraconnection fibres
IEC 61745 -  End-face image analysis procedure for the - -
calibration of optical fibre geometry test
sets

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SIST EN 60793-1-20:2015

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SIST EN 60793-1-20:2015




IEC 60793-1-20

®


Edition 2.0 2014-10




INTERNATIONAL



STANDARD




NORME



INTERNATIONALE
colour

inside










Optical fibres –

Part 1-20: Measurement methods and test procedures – Fibre geometry




Fibres optiques –

Partie 1-20: Méthodes de mesure et procédures d'essai – Géométrie de la fibre
















INTERNATIONAL

ELECTROTECHNICAL

COMMISSION


COMMISSION

ELECTROTECHNIQUE

PRICE CODE
INTERNATIONALE

CODE PRIX X


ICS 33.180.10 ISBN 978-2-8322-1884-6



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

Attention! Veuillez vous assurer que vous avez obtenu cette publication via un distributeur agréé.

® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale

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SIST EN 60793-1-20:2015
– 2 – IEC 60793-1-20:2014 © IEC 2014
CONTENTS
FOREWORD . 5
INTRODUCTION . 7
1 Scope . 8
2 Normative references . 8
3 Terms, definitions and symbols. 8
4 Overview of method . 10
4.1 General . 10
4.2 Scanning methods . 10
4.2.1 General . 10
4.2.2 One-dimensional scan sources of error . 11
4.2.3 Multidimensional scanning . 12
4.3 Data reduction . 13
4.3.1 Simple combination of few-angle scan sets . 13
4.3.2 Ellipse fitting of several-angle or raster data sets . 13
5 Reference test method . 13
6 Apparatus . 13
7 Sampling and specimens . 13
7.1 Specimen length . 13
7.2 Specimen end face . 13
8 Procedure . 13
9 Calculations . 14
10 Results . 14
11 Specification information . 14
Annex A (normative) Requirements specific to Method A – Refracted near-field. 15
A.1 Introductory remarks . 15
A.2 Apparatus . 15
A.2.1 Typical arrangement . 15
A.2.2 Source . 15
A.2.3 Launch optics . 15
A.2.4 XYZ positioner (scanning stage) . 16
A.2.5 Blocking disc . 16
A.2.6 Collection optics and detector . 17
A.2.7 Computer system . 17
A.2.8 Immersion cell . 17
A.3 Sampling and specimens . 17
A.4 Procedure . 17
A.4.1 Load and centre the fibre . 17
A.4.2 Line scan . 18
A.4.3 Raster scan . 18
A.4.4 Calibration . 18
A.5 Index of refraction calculation . 18
A.6 Calculations . 20
A.7 Results . 20
Annex B (normative) Requirements specific to Method B – Transmitted near-field . 21
B.1 Introductory remarks . 21

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SIST EN 60793-1-20:2015
IEC 60793-1-20:2014 © IEC 2014 – 3 –
B.2 Apparatus . 21
B.2.1 Typical arrangement . 21
B.2.2 Light sources . 22
B.2.3 Fibre support and positioning apparatus . 23
B.2.4 Cladding mode stripper . 23
B.2.5 Detection . 23
B.2.6 Magnifying optics . 24
B.2.7 Video image monitor (video grey-scale technique) . 25
B.2.8 Computer. 25
B.3 Sampling and specimens . 25
B.4 Procedure . 25
B.4.1 Equipment calibration . 25
B.4.2 Measurement . 25
B.5 Calculations . 27
B.6 Results . 27
Annex C (normative) Edge detection and edge table construction . 28
C.1 Introductory remarks . 28
C.2 Boundary detection by decision level . 28
C.2.1 General approach . 28
C.2.2 Class A multimode fibre core reference level and k factor . 29
C.2.3 Class B and C single-mode fibres . 30
C.2.4 Direct geometry computation of one-dimensional data . 30
C.3 Assembling edge tables from raw data . 31
C.3.1 General . 31
C.3.2 Edge tables from raster data . 31
C.3.3 Edge tables from multi-angular one-dimensional scans . 32
Annex D (normative) Edge table ellipse fitting and filtering. 33
D.1 Introductory remarks . 33
D.2 General mathematical expressions for ellipse fitting . 33
D.3 Edge table filtering . 34
D.4 Geometric parameter extraction . 35
Annex E (informative) Fitting category A1 core near-field data to a power law model . 36
E.1 Introductory remarks . 36
E.2 Preconditioning data for fitting . 36
E.2.1 Motivation . 36
E.2.2 Transformation of a two-dimensional image to one-dimensional radial
near-field . 36
E.2.3 Pre-processing of one-dimensional near-field data . 39
E.2.4 Baseline subtraction . 41
E.3 Fitting a power-law function to an category A1 fibre near-field profile . 41
Annex F (informative) Mapping class A core diameter measurements . 43
F.1 Introductory remarks . 43
F.2 Mapping function . 43
Bibliography . 44

Figure 1 – Sampling on a chord . 11
Figure 2 – Scan of a non-circular body . 12
Figure A.1 – Refracted near-field method – Cell . 16

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SIST EN 60793-1-20:2015
– 4 – IEC 60793-1-20:2014 © IEC 2014
Figure A.2 – Typical instrument arrangement . 16
Figure A.3– Typical index profile line scan of a category A1 fibre . 19
Figure A.4 – Typical raster index profile on a category A1 fibre . 19
Figure B.1 – Typical arrangement, grey scale technique . 21
Figure B.2 – Typical arrangement, mechanical scanning technique . 22
Figure B.3 – Typical 1-D near-field scan, category A1 core . 26
Figure B.4 − Typical raster near-field data, category A1 fibre . 27
Figure C.1 – Typical one-dimensional data set, cladding only . 29
Figure C.2 – Typical graded index core profile . 30
Figure C.3 – Raster data, cladding only . 31
Figure E.1 – Filtering concept . 38
Figure E.2 – Illustration of 1-D near-field preconditioning, typical video line . 40

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SIST EN 60793-1-20:2015
IEC 60793-1-20:2014 © IEC 2014 – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
______________

OPTICAL FIBRES –

Part 1-20: Measurement methods and test procedures –
Fibre geometry

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 60793-1-20 has been prepared by subcommittee SC86A: Fibre
and cables, of IEC technical committee TC86: Fibre optics.
This second edition cancels and replaces the first edition, published in 2001, and constitutes
a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
• the reference test method for all fibre types is changed to the video grey scale transmitted
near field method from the refracted near field method;
• the test lengths for all fibre types are now to be specified in the fibre’s detail specification;
• the core illumination wavelength for all multimode fibre types may now to be specified in
the fibre’s detail specification although defaults are given;

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SIST EN 60793-1-20:2015
– 6 – IEC 60793-1-20:2014 © IEC 2014
• the core k-factor (decision level) is now to be specified in the detail specification for all
multimode fibre types;
• this edition is substantially more specific in describing the measurement; data reduction
and transformation is fully described;
• the data reduction methodology for both refracted near-field and transmitted near-field
methods are now unified and consistent.
The text of this standard is based on the following documents:
CDV Report on voting
86A/1562/CDV 86A/1623/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.
This publication 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.
The committee has decided that the contents of this publication will remain unchanged until
the stability 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.

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 60793-1-20:2015
IEC 60793-1-20:2014 © IEC 2014 – 7 –
INTRODUCTION
This standard gives two methods for measuring fibre geometry characteristics:
– Method A: Refracted near-field, described in Annex A;
– Method B: Transmitted near-field, described in Annex B.
Methods A and B apply to the geometry measurement of all class A multimode fibres, class B
single-mode fibres and class C single-mode interconnection fibres. The fibre’s applicable
product specifications, IEC 60793-2-10, IEC 60793-2-20, IEC 60793-2-30, IEC 60793-2-40,
IEC 60793-2-50 and IEC 60793-2-60, provide relevant measurement details, including sample
lengths and k factors.
The geometric parameters measurable by the methods described in this standard are as
follows:
– cladding diameter;
– cladding non-circularity;
– core diameter (class A fibre only);
– core non-circularity (class A fibre only);
– core-cladding concentricity error.
NOTE 1 The core diameter of class B and class C fibres is not specified. The equivalent parameter is mode field
diameter, determined by IEC 60793-1-45.
NOTE 2 These methods specify both one-dimensional (1-D) and two-dimensional (2-D) data collection
techniques and data analyses. The 1-D methods by themselves cannot detemine non-circularity nor concentricity
error. When non-circular bodies are measured with 1-D methods, body diameters suffer additional uncertainties.
These limitations may be overcome by scanning and analysing multiple 1-D data sets. Clause 5 provides further
information.
Information common to both methods appears in Clauses 2 through 10, and information
pertaining to each individual method appears in Annexes A and B, respectively. Annex C
describes normative methods used to find the optical boundaries of the core and the cladding,
Annex D describes normative procedures to fit ellipses to sets of detected boundaries. Annex
E provides an informative fitting procedure of power-law models to graded-index core profiles.
Annex F describes an informative methodology relating to the transformation of core diameter
measurements determined with methods other than the reference method to approximate
reference method values.

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SIST EN 60793-1-20:2015
– 8 – IEC 60793-1-20:2014 © IEC 2014
OPTICAL FIBRES –

Part 1–20: Measurement methods and test procedures –
Fibre geometry



1 Scope
This part of IEC 60793 establishes uniform requirements for measuring the geometrical
characteristics of uncoated optical fibres.
The geometry of uncoated optical fibres directly affect splicing, connectorization and cabling
and so are fundamental parameters requiring careful specification, quality control, and thus
measurement.
2 Normative references
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.
IEC 60793-2-10, Optical fibres – Part 2-10: Product specifications – Sectional specification for
category A1 multimode fibres
IEC 60793-2-20, Optical fibres – Part 2-20: Product specifications – Sectional specification for
category A2 multimode fibres
IEC 60793-2-30, Optical fibres – Part 2-30: Product specifications – Sectional specification for
category A3 multimode fibres
IEC 60793-2-40, Optical fibres – Part 2-40: Product specifications – Specification for category
A4 multimode fibres
IEC 60793-2-50, Optical fibres – Part 2-50: Product specifications – Sectional specification for
class B single-mode fibres
IEC 60793-2-60, Optical fibres – Part 2-60: Product specifications – Sectional specification for
category C single-mode intraconnection fibres
IEC 61745, End-face image analysis procedure for the calibration of optical fibre geometry
test sets
3 Terms, definitions and symbols
3.1 Terms and definitions
For the purposes of this document, the following terms, definitions and symbols apply:
3.1.1
...