IEC 61280-1-4:2003

Fibre optic communication subsystem test procedures - Part 1-4: General communication subsystems - Collection and reduction of two-dimensional nearfield data for multimode fibre laser transmitters

Provides a procedure for the collection of two-dimensional fibre optic nearfield grayscale data and subsequent reduction to one-dimensional data expressed as a set of three sampled parametric functions of radius from the fibre's optical center. The object is to reduce measurement errors and inter-laboratory variation.

General Information

• Status: Published
• Publication Date: 22-Jan-2003
• ICS: 33.180.01 - Fibre optic systems in general
• Technical Committee: SC 86C - Fibre optic systems and active devices
• Drafting Committee: WG 1 - TC 86/SC 86C/WG 1
• Current Stage: DELPUB - Deleted Publication
• Completion Date: 20-Nov-2009

Relations

• Revised: IEC 61280-1-4:2009 - Fibre optic communication subsystem test procedures - Part 1-4: General communication subsystems - Light source encircled flux measurement method
• Effective Date: 05-Sep-2023

Standards Content (Sample)

INTERNATIONAL IEC
STANDARD
61280-1-4
First edition
2003-01
Fibre optic communication subsystem
test procedures –
Part 1-4:
General communication subsystems –
Collection and reduction of two-dimensional
nearfield data for multimode fibre laser
transmitters
Procédures d'essai des sous-systèmes
de télécommunication à fibres optiques –
Partie 1-4:
Procédures d'essai des sous-systèmes généraux
de télécommunication – Recueil et réduction de données
à deux dimensions de champs proches pour les
émetteurs de laser à fibres multimodales

Reference number
Publication numbering
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60000 series. For example, IEC 34-1 is now referred to as IEC 60034-1.

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edition numbers 1.0, 1.1 and 1.2 refer, respectively, to the base publication, the

base publication incorporating amendment 1 and the base publication incorporating

amendments 1 and 2.
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INTERNATIONAL IEC
STANDARD
61280-1-4
First edition
2003-01
Fibre optic communication subsystem
test procedures –
Part 1-4:
General communication subsystems –
Collection and reduction of two-dimensional
nearfield data for multimode fibre laser
transmitters
Procédures d'essai des sous-systèmes
de télécommunication à fibres optiques –
Partie 1-4:
Procédures d'essai des sous-systèmes généraux
de télécommunication – Recueil et réduction de données
à deux dimensions de champs proches pour les
émetteurs de laser à fibres multimodales

 IEC 2003  Copyright - all rights reserved
No part of this publication may be reproduced or utilized in any form or by any means, electronic or
mechanical, including photocopying and microfilm, without permission in writing from the publisher.
International Electrotechnical Commission, 3, rue de Varembé, PO Box 131, CH-1211 Geneva 20, Switzerland
Telephone: [phone] Telefax: [phone] E-mail: [e-mail]  Web: www.iec.ch
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R
International Electrotechnical Commission
Международная Электротехническая Комиссия
For price, see current catalogue

– 2 – 61280-1-4  IEC:2003(E)
CONTENTS
FOREWORD . 3

1 General . 4

1.1 Scope and object. 4

1.2 Assumptions . 4

2 Normative references. 5
3 Apparatus . 5
3.1 Sources . 5
3.1.1 Calibration source. 5
3.1.2 Laser under test. 5
3.2 Test jumper assembly. 6
3.3 Fibre shaker . 6
3.4 Micropositioner . 6
3.5 Microscope objective . 7
3.6 Detector. 7
4 Sampling and specimens . 7
5 Procedure. 7
5.1 Overview of the measurement procedure. 7
5.2 Camera calibration . 8
5.2.1 Camera geometric calibration . 8
5.2.2 Camera optical calibration. 9
5.3 Measuring 2D nearfield flux distributions . 9
5.4 Finding the optical center of the test jumper assembly. 9
5.5 Finding the nearfield distribution of a laser under test.10
6 Calculations or interpretation of results.10
6.1 Coordinate transforms .10
6.2 Centroid computation.11
6.3 Computation of radial data functions.12
7 Documentation.14
8 Specification information.15

Annex A (informative) Camera data reduction .16
Bibliography.20

61280-1-4  IEC:2003(E) – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION

____________
FIBRE OPTIC COMMUNICATION SUBSYSTEM TEST PROCEDURES –

Part 1-4: General communication subsystems –

Collection and reduction of two-dimensional nearfield data

for multimode fibre laser transmitters

FOREWORD
1) The IEC (International Electrotechnical Commission) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of the 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, the IEC publishes International Standards. 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. The IEC collaborates closely with the International
Organization for Standardization (ISO) in accordance with conditions determined by agreement between the
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from all interested National Committees.
3) The documents produced have the form of recommendations for international use and are published in the form
of standards, technical specifications, technical reports or guides and they are accepted by the National
Committees in that sense.
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divergence between the IEC Standard and the corresponding national or regional standard shall be clearly
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equipment declared to be in conformity with one of its standards.
6) Attention is drawn to the possibility that some of the elements of this International Standard may be the subject
of patent rights. The IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 61280-1-4 has been prepared by subcommittee 86C: Fibre optic
systems and active devices, of IEC technical committee 86: Fibre optics
The text of this standard is based on the following documents:
FDIS Report on voting
86C/465/FDIS 86C/494/RVD
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.
The committee has decided that the contents of this publication will remain unchanged until 2008.
At this date, the publication will be
• reconfirmed;
• withdrawn;
• replaced by a revised edition, or
• amended.
– 4 – 61280-1-4  IEC:2003(E)
FIBRE OPTIC COMMUNICATION SUBSYSTEM TEST PROCEDURES –

Part 1-4: General communication subsystems –

Collection and reduction of two-dimensional nearfield data

for multimode fibre laser transmitters

1 General
1.1 Scope and object
This part of IEC 61280 sets forth a standard procedure for the collection of two-dimensional
fibre optic nearfield grayscale data and subsequent reduction to one-dimensional data
expressed as a set of three sampled parametric functions of radius from the fibre’s optical
center. The object of this standard is to reduce measurement errors and inter-laboratory
variation, supporting accurate mathematical prediction of minimum guaranteed link length in
gigabit and ten gigabit fibre optic data communications systems.
These radial functions are intended to characterize fibre optic laser sources for use in
mathematical models predicting the minimum guaranteed length of a communications link.
Although available as a byproduct, estimation of the nearfield diameter is not an objective.
1.2 Assumptions
The 50-micron or 62,5-micron core near-parabolic graded-index multimode fibre used as the
“test jumper assembly” is treated as if it possessed perfect circular symmetry about its optical
center, as asymmetries in the launched optical flux distributions will dominate any
lopsidedness of the test jumper assembly. It is further assumed that all cladding modes will be
stripped by passage through the specified ten meters or more of fibre. The modes of a mode
group need not carry equal flux. (In fact, with such short fibres, one thousand meters or less,
unequal distribution of flux in the modes of a group is the norm, not the exception.)
The fibre micropositioner that moves the fibre in the receiving camera's field of view, being
used to calibrate the camera for geometric distortions, is used as a reference standard. The
microscope objective, used to project the magnified nearfield onto the CCD chip, is treated as
an optically perfect thick lens.
The flux detectors are required to be both linear and memoryless; this excludes for instance

lead sulphide vidicon detectors. Detectors shall meet the detector requirements of
IEC 60793-1-43. Absolute radiometric measurement of flux (optical power flow) is not
required. A computer is required to perform the needed computations, which are too extensive
to be performed manually. Although the present measurement method assumes a CCD
camera, mechanically-scanned “slitscan” and pinhole cameras may also be used.
Safety: all procedures in which an LED or laser source is used as the optical source shall be
carried out using safety precautions in accordance with IEC 60825-2.

61280-1-4  IEC:2003(E) – 5 –
2 Normative references
The following referenced documents are indispensable for the application of this document.

For dated references, only the edition cited applies. For undated references, the latest edition

of the referenced document (including any amendments) applies.

IEC 60793-1-20: Optical fibres – Part 1-20: Measurement methods and test procedures –

Fibre geometry
IEC 60793-1-41: Optical fibres – Part 1-41: Measurement methods and test procedures –

Bandwidth
IEC 60793-1-43: Optical fibres – Part 1-43: Measurement methods and test procedures –
Numerical aperture
IEC 60825-2: Safety of laser products – Part 2: Safety of optical fibre communication systems
3 Apparatus
As the objective of this international standard is to optically characterize laser sources, many
different laser sources will be used, while the rest of the apparatus is held constant. The
apparatus is calibrated using a broadband incoherent calibration source (such as a light-
emitting diode (LED) or a xenon arc lamp) in place of the lasers.
3.1 Sources
There are two kinds of sources used in the present measurement method: the incoherent
broadband overfilled source used for calibration, and the various laser sources
...