EN IEC 60793-1-34:2021

Optical fibres - Part 1-34: Measurement methods and test procedures - Fibre curl

IEC 60793-1-34:2021 is available as IEC 60793-1-34:2021 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.IEC 60793-1-34:2021 establishes uniform requirements for the mechanical characteristic: fibre curl or latent curvature in uncoated optical fibres, i.e. a specified length of the fibre has been stripped from coating. Fibre curl has been identified as an important parameter for minimizing the splice loss of optical fibres when using passive alignment fusion splicers or active alignment mass fusion splicers.Two methods are recognized for the measurement of fibre curl, in uncoated optical fibres: - method A: side view microscopy; - method B: laser beam scattering. Both methods measure the radius of curvature of an uncoated fibre by determining the amount of deflection that occurs as an unsupported fibre end is rotated about the fibre's axis. Method A uses visual or digital video methods to determine the deflection of the fibre while method B uses a line sensor to measure the maximum deflection of one laser beam relative to a reference laser beam. By measuring the deflection behaviour of the fibre as it is rotated about its axis and understanding the geometry of the measuring device, the fibre's radius of curvature can be calculated from simple circular models, the derivation of which are given in Annex C. Both methods are applicable to type B optical fibres as described in IEC 60793 (all parts). Method A is the reference test method, used to resolve disputes. This third edition cancels and replaces the second edition published in 2006. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition: - modification of several derivation equations for laser scattering; - change of angular increment from 10° to 30° to 10° to 45°; - change of Annex B from informative to normative.

Lichtwellenleiter - Teil 1-34: Messmethoden und Prüfverfahren - Faserringeln

Fibres optiques - Partie 1-34: Méthodes de mesure et procédures d'essai - Ondulation de la fibre

IEC 60793-1-34:2021 est disponible sous forme de IEC 60793-1-34:2021 RLV qui contient la Norme internationale et sa version Redline, illustrant les modifications du contenu technique depuis l'édition précédente.L'IEC 60793-1-34:2021 établit des exigences uniformes pour les caractéristiques mécaniques: ondulation de fibre ou courbure latente des fibres optiques sans revêtement, c'est-à-dire qu'une longueur spécifiée de la fibre a été dénudée. L'ondulation de fibre a été définie comme étant un paramètre important de réduction des pertes d'épissure des fibres optiques lors de l'utilisation de soudeuses par fusion avec alignement passif ou de soudeuses par fusion de masse avec alignement actif. Deux méthodes sont reconnues pour la mesure de l'ondulation de fibre, pour les fibres optiques sans revêtement: - méthode A: par microscopie latérale; - méthode B: par diffusion d'un faisceau laser. Les deux méthodes mesurent le rayon de courbure d'une fibre sans revêtement en déterminant la valeur de la flèche d'une extrémité de fibre non soutenue soumise à une rotation autour de son axe. La méthode A utilise des méthodes visuelles ou vidéo numériques pour déterminer la flèche de la fibre tandis que la méthode B utilise un capteur de ligne pour mesurer la flèche maximale d’un faisceau laser par rapport à un faisceau laser de référence. En mesurant le comportement de la flèche de la fibre pendant qu’elle est soumise à une rotation autour de son axe et d’après la configuration du dispositif de mesure, le rayon de courbure de la fibre peut être calculé à partir de modèles circulaires simples, déterminés à l’Annexe C. Ces deux méthodes sont applicables aux fibres optiques du type B telles que décrites dans la série IEC 60793 (toutes les parties). La méthode A est la méthode d'essai de référence, utilisée en cas de litige. Cette troisième édition annule et remplace la deuxième édition parue en 2006. Cette édition constitue une révision technique. Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente: - modification de plusieurs équations de détermination pour la diffusion laser; - modification de l'incrément angulaire qui passe de 10° à 30° à 10° à 45°; - changement de statut de l'Annexe B qui devient normative.

Optična vlakna - 1-34. del: Merilne metode in postopki preskušanja - Zvijanje vlaken (IEC 60793-1-34:2021)

General Information

• Status: Published
• Publication Date: 18-Mar-2021
• ICS: 33.180.10 - Fibres and cables
• Technical Committee: CLC/TC 86A - Optical fibres and optical fibre cables
• Drafting Committee: IEC/SC 86A - IEC_SC_86A
• Current Stage: 6060 - Document made available - Publishing
• Start Date: 19-Mar-2021
• Completion Date: 19-Mar-2021
• Ref Project: SIST EN IEC 60793-1-34:2021 - Optical fibres - Part 1-34: Measurement methods and test procedures - Fibre curl (IEC 60793-1-34:2021)

Relations

• Replaces: EN 60793-1-34:2006 - Optical fibres - Part 1-34: Measurement methods and test procedures - Fibre curl
• Effective Date: 11-Jun-2019

Overview

EN IEC 60793-1-34:2021 (IEC 60793-1-34:2021) defines standardized measurement methods and test procedures for fibre curl (latent curvature) in uncoated optical fibres. Published as part of the IEC 60793 series and adopted by CLC/CENELEC, this third edition (2021) replaces the 2006 version and provides uniform requirements for quantifying fibre curl - a mechanical characteristic that affects splice loss when using passive or active alignment fusion splicers.

Key topics and requirements

• Scope: Measurement of fibre curl (radius of curvature) on uncoated optical fibres (specified stripped length).
• Two accepted measurement methods:
  • Method A - Side view microscopy: Visual or digital video imaging records deflection as the unsupported fibre end is rotated about its axis. This is the reference test method used to resolve disputes.
  • Method B - Laser beam scattering: A laser source and line sensor measure the maximum deflection of a probe beam relative to a reference beam while the fibre is rotated.
• Measurement principle: Both methods determine radius of curvature from the angular deflection of the rotating fibre and the geometry of the measuring device; circular-model derivations are provided (Annex C).
• Test details and procedures: Apparatus, sample preparation, mounting, rotation increments, calculation and reporting rules are specified. Annex A (normative) details side view microscopy; Annex B (now normative) covers laser scattering.
• 2021 technical changes: Modifications to laser-scattering derivation equations, change in angular increment range (from 10°–30° to 10°–45°), and Annex B elevated to normative status.

Practical applications

• Ensures consistent, repeatable fibre curl measurement for quality control and acceptance testing.
• Helps manufacturers and test laboratories minimize splice loss by characterizing latent curvature before connectorization or mass fusion splicing.
• Supports equipment manufacturers (fusion splicers, inspection systems) in aligning product specifications and test methods.
• Useful for R&D when evaluating new fibre coatings, draw processes, or mechanical handling that influence curl.

Who should use this standard

• Optical fibre manufacturers and suppliers
• Independent testing and certification laboratories
• Fusion splicer and fibre-handling equipment designers
• Network operators and installers concerned with splicing yield and reliability
• Standards and quality managers in optical component supply chains

Related standards

• IEC 60793 series - Optical fibres: this part (1-34) is a component of the broader IEC 60793 family and references the generic specification and type definitions in other parts of the series.

Keywords: optical fibres, fibre curl, IEC 60793-1-34, measurement methods, side view microscopy, laser beam scattering, splice loss, fusion splicer, radius of curvature, test procedures.

Standards Content (Sample)

SLOVENSKI STANDARD
01-junij-2021
Nadomešča:
SIST EN 60793-1-34:2006
Optična vlakna - 1-34. del: Merilne metode in postopki preskušanja - Zvijanje
vlaken (IEC 60793-1-34:2021)
Optical fibres - Part 1-34: Measurement methods and test procedures - Fibre curl (IEC
60793-1-34:2021)
Lichtwellenleiter - Teil 1-34: Messmethoden und Prüfverfahren - Faserringeln (IEC 60793
-1-34:2021)
Fibres optiques - Partie 1-34: Méthodes de mesure et procédures d'essai - Ondulation
de la fibre (IEC 60793-1-34:2021)
Ta slovenski standard je istoveten z: EN IEC 60793-1-34:2021
ICS:
33.180.10 (Optična) vlakna in kabli Fibres and cables
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD EN IEC 60793-1-34

NORME EUROPÉENNE
EUROPÄISCHE NORM
March 2021
ICS 33.180.10 Supersedes EN 60793-1-34:2006 and all of its
amendments and corrigenda (if any)
English Version
Optical fibres - Part 1-34: Measurement methods and test
procedures - Fibre curl
(IEC 60793-1-34:2021)
Fibres optiques - Partie 1-34: Méthodes de mesure et Lichtwellenleiter - Teil 1-34: Messmethoden und
procédures d'essai - Ondulation de la fibre Prüfverfahren - Faserringeln
(IEC 60793-1-34:2021) (IEC 60793-1-34:2021)
This European Standard was approved by CENELEC on 2021-03-17. 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, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the
Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, 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: Rue de la Science 23, B-1040 Brussels
© 2021 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN IEC 60793-1-34:2021 E

European foreword
The text of document 86A/1971/CDV, future edition 3 of IEC 60793-1-34, 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 IEC 60793-1-34:2021.
The following dates are fixed:
• latest date by which the document has to be implemented at national (dop) 2021-12-17
level by publication of an identical national standard or by endorsement
• latest date by which the national standards conflicting with the (dow) 2024-03-17
document have to be withdrawn
This document supersedes EN 60793-1-34:2006 and all of its amendments and corrigenda (if any).
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 60793-1-34:2021 was approved by CENELEC as a
European Standard without any modification.
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
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.
NOTE 1  Where 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 series Optical fibres - Part 1: Generic specification EN IEC 60793 series

IEC 60793-1-34 ®
Edition 3.0 2021-02
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Optical fibres –
Part 1-34: Measurement methods and test procedures – Fibre curl

Fibres optiques –
Partie 1-34: Méthodes de mesure et procédures d’essai – Ondulation de la fibre

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 33.180.10 ISBN 978-2-8322-9396-6

– 2 – IEC 60793-1-34:2021  IEC 2021
CONTENTS
FOREWORD . 4
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
4 Apparatus . 7
4.1 Principle . 7
4.2 Fibre holding fixture . 7
4.3 Fibre rotator . 7
4.4 Deflection measurement device . 7
4.5 Computer (optional) . 7
5 Sample preparation . 7
6 Procedure . 7
6.1 General . 7
6.2 Mounting of the fibre . 7
6.3 Rotation . 8
7 Calculation . 8
8 Result . 8
9 Specification information . 8
Annex A (normative) Fibre curl by side view microscopy . 9
A.1 Principle . 9
A.2 Apparatus . 10
A.2.1 Deflection measurement device . 10
A.2.2 Video camera and monitor . 11
A.2.3 Digital image analysis system (optional) . 11
A.3 Test procedure . 11
A.3.1 General . 11
A.3.2 Procedure for the extrema technique . 11
A.3.3 Procedure for the Fourier fitting technique . 11
A.4 Calculations . 11
A.4.1 Extrema technique calculation . 11
A.4.2 Fourier fitting technique calculation . 11
A.4.3 Computation of fibre curl. 12
Annex B (normative) Fibre curl by laser beam scattering . 13
B.1 Principle . 13
B.2 Apparatus . 13
B.2.1 Light source . 13
B.2.2 Detector . 13
B.3 Test procedure . 13
B.3.1 General . 13
B.3.2 Procedure for the extrema technique . 13
B.3.3 Procedure for the Fourier fitting technique . 13
B.4 Calculations . 13
B.4.1 Extrema technique calculation . 13
B.4.2 Fourier fitting technique calculation . 14
B.4.3 Computation of fibre curl. 14

IEC 60793-1-34:2021  IEC 2021 – 3 –
Annex C (informative) Derivation of the circular fibre curl model . 15
C.1 Derivation of equations for side view microscopy . 15
C.2 Derivation of equations for the laser scattering method . 16

Figure A.1 – Schematic diagram for apparatus to measure fibre curl using an optical
microscope . 9
Figure A.2 – Schematic diagram for apparatus to measure fibre curl using a laser
micrometer. 10
Figure A.3 – Schematic diagram for apparatus to measure fibre curl while securing the

sample in a ferrule . 10
Figure B.1 – Schematic diagram of optical curl by laser beam scattering . 14
Figure C.1 – Geometrical layout of side view microscopy fibre curl measurement . 15
Figure C.2 – Geometrical layout of laser scattering fibre curl measurement . 16

– 4 – IEC 60793-1-34:2021  IEC 2021
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
OPTICAL FIBRES –
Part 1-34: Measurement methods and test procedures – Fibre curl

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 60793-1-34 has been prepared by subcommittee 86A: Fibres and
cables, of IEC technical committee 86: Fibre optics.
This third edition cancels and replaces the second edition published in 2006. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) modification of several derivation equations for laser scattering;
b) change of angular increment from 10° to 30° to 10° to 45°;
c) change of Annex B from informative to normative.
The text of this International Standard is based on the following documents:
CDV Report on voting
86A/1971/CDV 86A/1994/RVC
IEC 60793-1-34:2021  IEC 2021 – 5 –

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.
The committee has decided that the contents of this document will remai
...