National foreword

This Published Document reproduces verbatim IEC TR 62284:2003.

The UK participation in its preparation was entrusted by Technical Committee GEL/86, Fibre optics, to Subcommittee GEL/86/1, Optical fibres and cables, which has the responsibility to:

aid enquirers to understand the text;
present to the responsible international/European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed;
monitor related international and European developments and promulgate them in the UK.

A list of organizations represented on this subcommittee can be obtained on request to its secretary.

Cross-references

The British Standards which implement international publications referred to in this document may be found in the BSI Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standards Online.

Summary of pages

This document comprises a front cover, an inside front cover, the IEC TR title page, pages 2 to 40, an inside back cover and a back cover.

The BSI copyright date displayed in this document indicates when the document was last issued.

This Published Document was published under the authority of the Standards Policy and Strategy Committee on 10 March 2003

FOREWORD

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 two organizations.
The formal decisions or agreements of the 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 National Committees.
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.
In order to promote international unification, IEC National Committees undertake to apply IEC International Standards transparently to the maximum extent possible in their national and regional standards. Any divergence between the IEC Standard and the corresponding national or regional standard shall be clearly indicated in the latter.
The IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any equipment declared to be in conformity with one of its standards.
Attention is drawn to the possibility that some of the elements of this technical report may be the subject of patent rights. The IEC shall not be held responsible for identifying any or all such patent rights.

The main task of IEC technical committees is to prepare International Standards. However, a technical committee may propose the publication of a technical report when it has collected data of a different kind from that which is normally published as an International Standard, for example "state of the art".

IEC 62284, which is a technical report, has been prepared by subcommittee 86A: Fibres and cables, of IEC technical committee 86: Fibre optics.

The text of this technical report is based on the following documents:

Full information on the voting for the approval of this technical report 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 2004. At this date, the publication will be

reconfirmed;
withdrawn;
replaced by a revised edition, or
amended.

1 Scope and object

This technical report applies to single-mode optical fibres. Its object is to document the methods for measuring the effective area (A_eff) of these fibres.

It defines three methods of measuring A_eff. Information common to all the methods is found in the body of this document. Information specific to each method is found in the annexes. The three methods are:

direct far-field (DFF)
variable aperture in the far-field (VAMFF)
near-field (NF)

The reference method, used to resolve disputes, is method A, direct far field.

Effective area is an optical attribute that is specified for single-mode fibres and used in system designs that may be affected by the non-linear refractive index coefficient, n₂. There is agreement in both national and international standards bodies concerning the definition used in this technical report. Methods A, B, and C have been recognised as providing equivalent results, provided that good engineering is used in implementation.

The direct far-field is the reference method because it is the most direct method and is named as the reference method for mode field diameter in the ITU.

A mapping function is a formula by which the measured results of one attribute are used to predict the value of another attribute on a given fibre. For a given fibre type and design, the mode field diameter (MFD) (IEC 60793‑1‑45) can be used to predict the effective area with a mapping function. A mapping function is specific to a particular fibre type and design. Mapping functions are generated by doing an experiment in which a sample of fibre is chosen to represent the spectrum of values of MFD and in which the fibres in the sample are measured for both MFD and A_eff. Linear regression can be used to determine the fitting coefficient, k, as defined by the following:

NOTE Other mathematical models may be used if they are generally more accurate.

2 Reference documents

3 Apparatus

3.1 Light source

3.2 Input optics

3.3 Cladding mode stripper

3.4 High-order mode filter

3.5 Computer

4 Sampling and specimens

4.1 Specimen length

4.2 Specimen end faces

5 Procedure

6 Calculation or interpretation of results

6.1 Near-field

6.2 Direct far-field

6.3 Variable aperture in the far-field

7 Documentation

7.1 Information to be reported with each measurement

7.2 Information that should be available upon request

References

PD IEC TR 62284:2003

Effective area measurements of single-mode optical fibres. Guidance

Published:

21 Jan 2003

Withdrawn:

9 Dec 2025