Fibre optic interconnecting devices and passive components - Basic test and measurement procedures - Part 3-53: Examinations and Measurements - Encircled angular flux (EAF) measurement method based on two-dimensional far field data from multimode waveguide (including fibre) (IEC 61300-3-53:2020)

This part of IEC 61300 defines the encircled angular flux measurement of multimode waveguide light sources, in which most of the transverse modes are excited. The term "waveguide" is understood to include both channel waveguides and optical fibres but not slab waveguides. The applicable fibre types are the followings: - A1 specified in IEC 60793-2-10; - A3 specified in IEC 60793-2-30; - A4 specified in IEC 60793-2-40.

Lichtwellenleiter - Verbindungselemente und passive Bauteile - Grundlegende Prüf- und Messverfahren - Teil 3-53: Untersuchungen und Messungen - Verfahren zur Messung des winkelabhängigen begrenzten Lichtstroms (EAF) basierend auf den zweidimensionalen Fernfelddaten eines Mehrmoden-Wellenleiters (einschließlich -Faser) (IEC 61300-3-53:2020)

Dispositifs d'interconnexion et composants passifs fibroniques - Procédures fondamentales d'essais et de mesures - Partie 3-53: Examens et mesures - Méthode de mesure du flux angulaire inscrit (EAF) fondée sur les données bidimensionnelles de champ lointain d’un guide d’ondes multimodal (fibre incluse) (IEC 61300-3-53:2020)

IEC 61300-3-53:2020 est disponible sous forme de IEC 61300-3-53:2020 RLV qui contient la Norme internationale et sa version Redline, illustrant les modifications du contenu technique depuis l'�dition pr�c�dente.L'IEC 61300-3-53:2020 définit la mesure du flux angulaire inscrit de sources de rayonnement lumineux dotées d’un guide d’ondes multimodal, pour lequel la plupart des modes transversaux sont excités. On considère que le terme "guide d’ondes" inclut à la fois des guides d’ondes de canal et des fibres optiques, mais pas des guides d’ondes rectangulaires rigides. Les types de fibres applicables sont les suivants: - A1 spécifié dans l’IEC 60793-2-10; - A3 spécifié dans l’IEC 60793-2-30; - A4 spécifié dans l’IEC 60793-2-40. Cette deuxième édition annule et remplace la première édition parue en 2015. Cette édition constitue une révision technique. Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente: - la portée des guides d’ondes applicables, ainsi que la fibre et le guide d’ondes optiques multimodaux à gradient d’indice ont été inclus; - restructuration de 5.3; - ajout de l'Annexe C et de l'Annexe D.

Optični spojni elementi in pasivne komponente - Osnovni preskusni in merilni postopki - 3-53. del: Preiskave in meritve - Merilna metoda obdanega koničastega pretoka (EAF), osnovana na dvodimenzionalnih podatkih daljnega polja iz mnogorodovnega valovoda (vključno z optičnim vlaknom) (IEC 61300-3-53:2020)

General Information

Status
Published
Publication Date
15-Feb-2021
Technical Committee
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
12-Feb-2021
Due Date
19-Apr-2021
Completion Date
16-Feb-2021

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SLOVENSKI STANDARD
SIST EN IEC 61300-3-53:2021
01-april-2021
Nadomešča:
SIST EN 61300-3-53:2015
Optični spojni elementi in pasivne komponente - Osnovni preskusni in merilni
postopki - 3-53. del: Preiskave in meritve - Merilna metoda obdanega koničastega
pretoka (EAF), osnovana na dvodimenzionalnih podatkih daljnega polja iz
mnogorodovnega valovoda (vključno z optičnim vlaknom) (IEC 61300-3-53:2020)
Fibre optic interconnecting devices and passive components - Basic test and
measurement procedures - Part 3-53: Examinations and Measurements - Encircled

angular flux (EAF) measurement method based on two-dimensional far field data from

multimode waveguide (including fibre) (IEC 61300-3-53:2020)

Lichtwellenleiter - Verbindungselemente und passive Bauteile - Grundlegende Prüf- und

Messverfahren - Teil 3-53: Untersuchungen und Messungen - Verfahren zur Messung
des winkelabhängigen begrenzten Lichtstroms (EAF) basierend auf den

zweidimensionalen Fernfelddaten eines Mehrmoden-Wellenleiters (einschließlich -Faser)

(IEC 61300-3-53:2020)
Dispositifs d'interconnexion et composants passifs fibroniques - Procédures

fondamentales d'essais et de mesures - Partie 3-53: Examens et mesures - Méthode de

mesure du flux angulaire inscrit (EAF) fondée sur les données bidimensionnelles de

champ lointain d’un guide d’ondes multimodal (fibre incluse) (IEC 61300-3-53:2020)

Ta slovenski standard je istoveten z: EN IEC 61300-3-53:2021
ICS:
33.180.20 Povezovalne naprave za Fibre optic interconnecting
optična vlakna devices
SIST EN IEC 61300-3-53:2021 en

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN IEC 61300-3-53:2021
---------------------- Page: 2 ----------------------
SIST EN IEC 61300-3-53:2021
EUROPEAN STANDARD EN IEC 61300-3-53
NORME EUROPÉENNE
EUROPÄISCHE NORM
February 2021
ICS 33.180.20 Supersedes EN 61300-3-53:2015 and all of its
amendments and corrigenda (if any)
English Version
Fibre optic interconnecting devices and passive components -
Basic test and measurement procedures - Part 3-53:
Examinations and measurements - Encircled angular flux (EAF)
measurement method based on two-dimensional far field data
from multimode waveguide (including fibre)
(IEC 61300-3-53:2020)

Dispositifs d'interconnexion et composants passifs Lichtwellenleiter - Verbindungselemente und passive

fibroniques - Procédures fondamentales d'essais et de Bauteile - Grundlegende Prüf- und Messverfahren - Teil 3-

mesures - Partie 3-53: Examens et mesures - Méthode de 53: Untersuchungen und Messungen - Verfahren zur

mesure du flux angulaire inscrit (EAF) fondée sur les Messung des winkelabhängigen begrenzten Lichtstroms

données bidimensionnelles de champ lointain d'un guide (EAF) basierend auf den zweidimensionalen Fernfelddaten

d'ondes multimodal (fibre incluse) eines Mehrmoden-Wellenleiters (einschließlich -Faser)

(IEC 61300-3-53:2020) (IEC 61300-3-53:2020)

This European Standard was approved by CENELEC on 2021-01-19. 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 61300-3-53:2021 E
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SIST EN IEC 61300-3-53:2021
EN IEC 61300-3-53:2021 (E)
European foreword

The text of document 86B/4343/FDIS, future edition 2 of IEC 61300-3-53, prepared by SC 86B "Fibre

optic interconnecting devices and passive components" of IEC/TC 86 "Fibre optics" was submitted to

the IEC-CENELEC parallel vote and approved by CENELEC as EN IEC 61300-3-53:2021.
The following dates are fixed:

• latest date by which the document has to be implemented at national (dop) 2021-10-19

level by publication of an identical national standard or by endorsement

• latest date by which the national standards conflicting with the (dow) 2024-01-19

document have to be withdrawn

This document supersedes EN 61300-3-53:2015 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 61300-3-53:2020 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 61745 NOTE Harmonized as EN 61745
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SIST EN IEC 61300-3-53:2021
EN IEC 61300-3-53:2021 (E)
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 60793-2-10 - Optical fibres - Part 2-10: Product EN IEC 60793-2-10 -
specifications - Sectional specification for
category A1 multimode fibres
IEC 60793-2-30 - Optical fibres - Part 2-30: Product EN 60793-2-30 -
specifications - Sectional specification for
category A3 multimode fibres
IEC 60793-2-40 - Optical fibres - Part 2-40: Product EN 60793-2-40 -
specifications - Sectional specification for
category A4 multimode fibres
IEC 60825-1 - Safety of laser products - Part 1: EN 60825-1 -
Equipment classification and requirements
IEC 61300-1 2016 Fibre optic interconnecting devices and EN 61300-1 2016
passive components - Basic test and
measurement procedures - Part 1: General
and guidance
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SIST EN IEC 61300-3-53:2021
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SIST EN IEC 61300-3-53:2021
IEC 61300-3-53
Edition 2.0 2020-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Fibre optic interconnecting devices and passive components – Basic test and
measurement procedures
Part 3-53: Examinations and measurements – Encircled angular flux (EAF)
measurement method based on two-dimensional far field data from multimode
waveguide (including fibre)
Dispositifs d'interconnexion et composants passifs fibroniques – Procédures
fondamentales d'essais et de mesures –
Partie 3-53: Examens et mesures – Méthode de mesure du flux angulaire inscrit
(EAF) fondée sur les données bidimensionnelles de champ lointain d’un guide
d’ondes multimodal (fibre incluse)
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 33.180.20 ISBN 978-2-8322-9136-8

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
---------------------- Page: 7 ----------------------
SIST EN IEC 61300-3-53:2021
– 2 – IEC 61300-3-53:2020 © IEC 2020
CONTENTS

FOREWORD ........................................................................................................................... 4

1 Scope .............................................................................................................................. 6

2 Normative references ...................................................................................................... 6

3 Terms and definitions ...................................................................................................... 6

4 Measurement conditions .................................................................................................. 8

5 Apparatus ........................................................................................................................ 8

5.1 General ................................................................................................................... 8

5.2 Measurement method 1: fθ lens imaging ................................................................. 8

5.2.1 General ........................................................................................................... 8

5.2.2 Micro-positioner ............................................................................................... 8

5.2.3 FFP optical system .......................................................................................... 9

5.2.4 Imaging device ................................................................................................ 9

5.2.5 Computer (EAF analyser module) .................................................................... 9

5.3 Measurement method 2: direct imaging ................................................................... 9

5.3.1 General ........................................................................................................... 9

5.3.2 Micro-positioner ............................................................................................... 9

5.3.3 Imaging device .............................................................................................. 10

5.3.4 Computer, position controller and image acquisition ...................................... 10

6 Sampling and specimens ............................................................................................... 10

7 Geometric calibration ..................................................................................................... 10

7.1 General ................................................................................................................. 10

7.2 Light source .......................................................................................................... 11

7.3 Procedure ............................................................................................................. 11

8 Measurement procedure ................................................................................................ 11

8.1 Safety ................................................................................................................... 11

8.2 Far field image acquisition .................................................................................... 12

8.2.1 General ......................................................................................................... 12

8.2.2 Waveguide end-face alignment ...................................................................... 12

8.2.3 Light source image acquisition ....................................................................... 12

8.3 Removal of background noise ............................................................................... 13

8.4 Centre determination ............................................................................................ 13

8.4.1 General ......................................................................................................... 13

8.4.2 Method A: Optical centre determination ......................................................... 13

8.4.3 Method B: Mechanical centre determination ................................................... 14

8.5 Computation of encircled angular flux ................................................................... 15

9 Results .......................................................................................................................... 16

9.1 Information available with each measurement ....................................................... 16

9.2 Information available upon request ....................................................................... 17

10 Details to be specified ................................................................................................... 17

Annex A (informative) System recommendations – Measurement method 1: far field

optical system ....................................................................................................................... 18

A.1 General ................................................................................................................. 18

A.2 Recommendations ................................................................................................ 18

Annex B (informative) System recommendations – Measurement method 2: direct

imaging ................................................................................................................................. 19

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SIST EN IEC 61300-3-53:2021
IEC 61300-3-53:2020 © IEC 2020 – 3 –

B.1 General ................................................................................................................. 19

B.2 Recommendations ................................................................................................ 19

Annex C (informative) Shading effect of CCD devices: incident ray angular sensitivity ......... 20

C.1 General ................................................................................................................. 20

C.2 Scheme of shading and example of the characteristics ......................................... 20

Annex D (normative) Launch optics for the EAF template compliance test ........................... 22

D.1 General ................................................................................................................. 22

D.2 Setup .................................................................................................................... 22

Bibliography .......................................................................................................................... 23

Figure 1 – Apparatus configuration of measurement method 1: fθ lens imaging ....................... 8

Figure 2 – Far field optical system diagram ............................................................................. 9

Figure 3 – Apparatus configuration of measurement method 2: direct imaging ...................... 10

Figure 4 – Calibration apparatus example ............................................................................. 11

Figure 5 – Acquired far field image ....................................................................................... 12

Figure 6 – Acquired far field image with false colour ............................................................. 13

Figure 7 – Optical centre determination ................................................................................ 14

Figure 8 – Transformation of x-y to polar coordinates on the image sensor plane ................. 15

Figure 9 – Typical encircled angular flux chart ...................................................................... 16

Figure A.1 – An example of an optical system using an fθ lens ............................................. 18

Figure C.1 – Scheme of shading effect ................................................................................. 20

Figure C.2 – Example of shading characteristics ................................................................... 21

Figure D.1 – Schematic view of the setup for the EAF compliance test ................................. 22

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SIST EN IEC 61300-3-53:2021
– 4 – IEC 61300-3-53:2020 © IEC 2020
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
FIBRE OPTIC INTERCONNECTING
DEVICES AND PASSIVE COMPONENTS –
BASIC TEST AND MEASUREMENT PROCEDURES
Part 3-53: Examinations and measurements – Encircled angular
flux (EAF) measurement method based on two-dimensional
far field data from multimode waveguide (including fibre)
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 61300-3-53 has been prepared by subcommittee 86B: Fibre optic

interconnecting devices and passive components, of IEC technical committee 86:Fibre optics.

This second edition cancels and replaces the first edition in 2015. This edition constitutes a

technical revision.

This edition includes the following significant technical changes with respect to the previous

edition:

a) the scope of the applicable wave guides, and graded index multimode optical wave guide

and fibre have been included;
b) the structure of 5.3 has been rearranged;
c) Annex C and Annex D have been added.
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SIST EN IEC 61300-3-53:2021
IEC 61300-3-53:2020 © IEC 2020 – 5 –
The text of this International Standard is based on the following documents:
FDIS Report on voting
86B/4343/FDIS 86B/4373/RVD

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 61300, published under the general title Fibre optic interconnecting

devices and passive components – Basic test and measurement procedures, can be found on

the IEC website.

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.

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 IEC 61300-3-53:2021
– 6 – IEC 61300-3-53:2020 © IEC 2020
FIBRE OPTIC INTERCONNECTING
DEVICES AND PASSIVE COMPONENTS –
BASIC TEST AND MEASUREMENT PROCEDURES
Part 3-53: Examinations and measurements – Encircled angular
flux (EAF) measurement method based on two-dimensional
far field data from multimode waveguide (including fibre)
1 Scope

This part of IEC 61300 defines the encircled angular flux measurement of multimode waveguide

light sources, in which most of the transverse modes are excited. The term "waveguide" is

understood to include both channel waveguides and optical fibres but not slab waveguides.

The applicable fibre types are the followings:
• A1 specified in IEC 60793-2-10;
• A3 specified in IEC 60793-2-30;
• A4 specified in IEC 60793-2-40.
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 60793-2-10, Optical fibres – Part 2-10: Product specifications – Sectional specification for

category A1 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 – Sectional specification for

category A4 multimode fibres

IEC 60825-1, Safety of laser products – Part 1: Equipment classification and requirements

IEC 61300-1:2016, Fibre optic interconnecting devices and passive components – Basic test

and measurement procedures – Part 1: General and guidance
3 Terms and definitions
For the purposes of this document, the following terms and definitions 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
---------------------- Page: 12 ----------------------
SIST EN IEC 61300-3-53:2021
IEC 61300-3-53:2020 © IEC 2020 – 7 –
3.1
encircled angular flux
EAF

fraction of the total optical power radiating from a multimode waveguide’s core within a certain

solid angle
3.2
Fraunhofer far field
far field which occurs when
L ≫ D /λ
where
L is the distance of the detection plane from the waveguide end facet;

D is the diameter of the multimode waveguide core or strictly mode field diameter;

λ is the wavelength.
3.3
fθ lens

lens converting the angle of incidence of the input beam, θ, into the output beam height, h

Note 1 to entry: The relationship between them is h = fθ, where f is the focal length of the lens.

3.4
mode power distribution
MPD
relative mode power in each of the mode groups of a multimode fibre

[SOURCE: IEC 62614-2:2015, 3.5, modified – The words "often shown graphically" have been

deleted.]
3.5
numerical aperture

sine of the vertex half-angle of the largest cone of meridional rays that can enter or leave the

core of an optical waveguide, multiplied by the refractive index of the medium in which the cone

is located
3.6
far field pattern
FFP

angular distribution of light radiating from a waveguide’s core, which corresponds to the optical

power distribution on a plane normal to the waveguide axis some distance from its end facet

Note 1 to entry: The distance depends on the largest waveguide cross section, a, the wavelength, λ, and the angle,φ,

to the optical axis. In the far field region, the shape of the distribution does not change as the distance from the

waveguide end facet increases; the distribution only scales in size with distance, L.

2a cos φ
( )
L>>
3.7
far field image
far field pattern formed on an imaging device
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SIST EN IEC 61300-3-53:2021
– 8 – IEC 61300-3-53:2020 © IEC 2020
3.8
neutral density filter
ND filter
filter that attenuates light of all colours equally
4 Measurement conditions

Optical fibres which are applied to this measurement are specified in IEC 60793-2-10,

IEC 60793-2-30 and IEC 60793-2-40. The measurement ambient condition shall be the

standard atmospheric conditions specified in IEC 61300-1.
5 Apparatus
5.1 General

The optical source multimode waveguide shall be long enough to ensure that all cladding modes

are stripped by passage through the waveguide. Often, the fibre coating or tight buffer is

sufficient to perform this function. Alternatively, a cladding mode stripper shall be used in the

source launch multimode optical fibre. An example of a typical cladding mode stripper which

would be suitable for optical fibre is sufficient windings of the fibre around a mandrel of an

appropriate diameter. The windings also have a more important essential effect to fully fill the

transverse modes across the maximum mode field diameter. It should be checked that all of the

transverse modes of the fibre are sufficiently well excited. See Annex D. This can be done by

comparing the FFPs for different lengths of the launch fibre or different light sources. Once the

FFP no longer changes in form as the launch fibre length is increased, there is no need to

increase the length further.
5.2 Measurement method 1: fθ lens imaging
5.2.1 General

In theory, this measurement method, which is effectively a coherent optical method to Fourier

transform the near field to the far field using a lens, does not operate well using very wideband

optical sources. Experimentally, it has been shown to operate sufficiently well for sources up to

30 nm bandwidth, which are most commonly used.

Figure 1 below shows the apparatus configuration. The measurement system consists of a

micro-positioner, a far field broadband optical system, an imaging device (e.g. camera) and

computer (EAF analyser module). An appropriate type of camera (imaging device) shall be

chosen to suit the wavelength under test.
Figure 1 – Apparatus configuration of measurement method 1: fθ lens imaging
5.2.2 Micro-positioner

The micro-positioner shall hold the optical source (including the waveguide) and be able to

move in three directions (X, Y, Z). Angular movement for the optical system is recommended.

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SIST EN IEC 61300-3-53:2021
IEC 61300-3-53:2020 © IEC 2020 – 9 –
5.2.3 FFP optical system

As shown in Figure 2, an fθ lens can directly convert the light from the multimode waveguide to

a far field image; however, scaling the far field image in order to fit the image sensor in the

imaging device and adjustment of the light intensity in order to prevent saturation is required.

The FFP optical system is chosen to operate at the measurement wavelength across the

required measurement bandwidth to match that of the detection system. See Annex A for more

information.
Figure 2 – Far field optical system diagram
...

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