EN IEC 61280-1-3:2021

Fibre optic communication subsystem test procedures - Part 1-3: General communication subsystems - Measurement of central wavelength, spectral width and additional spectral characteristics

This part of IEC 61280 provides definitions and measurement procedures for several wavelength and spectral width properties of an optical spectrum associated with a fibre optic communication subsystem, an optical transmitter, or other light sources used in the operation or test of communication subsystems. This document also provides definitions and measurement procedures for side mode suppression ratio and signal to source spontaneous emission ratio. The measurement is done for the purpose of system construction and/or maintenance. In the case of communication subsystem signals, the optical transmitter is typically under modulation. NOTE Different properties may be appropriate to different spectral types, such as continuous spectra characteristic of light-emitting diodes (LEDs), and multilongitudinal-mode (MLM), multitransverse-mode (MTM) and single-longitudinal mode (SLM) spectra, characteristic of laser diodes (LDs).

Prüfverfahren für Lichtwellenleiter-Kommunikationsuntersysteme - Teil 1-3: Allgemeine Kommunikationsuntersysteme - Messung von Mittenwellenlänge, Spektralbreite und weiteren Spektralkennwerten

Procédures d’essai des sous-systèmes de télécommunication à fibres optiques - Partie 1-3: Sous-systèmes généraux de télécommunication - Mesure de la longueur d'onde centrale, de la largeur spectrale et des caractéristiques spectrales supplémentaires

IEC 61280-1-3:2021 est disponible sous forme de IEC 61280-1-3:2021 RLV qui contient la Norme internationale et sa version Redline, illustrant les modifications du contenu technique depuis l'édition précédente.

Postopki preskušanja optičnega komunikacijskega podsistema - 1-3. del: Splošni komunikacijski podsistemi - Merjenje osrednje valovne dolžine, spektralne širine in dodatnih spektralnih značilnosti (IEC 61280-1-3:2021)

General Information

• Status: Published
• Publication Date: 26-Aug-2021
• ICS: 33.180.01 - Fibre optic systems in general
• Technical Committee: CLC/SR 86C - Fibre optic systems and active devices
• Drafting Committee: IEC/SC 86C - IEC_SC_86C
• Current Stage: 6060 - Document made available - Publishing
• Start Date: 27-Aug-2021
• Completion Date: 27-Aug-2021
• Ref Project: SIST EN IEC 61280-1-3:2021 - Fibre optic communication subsystem test procedures - Part 1-3: General communication subsystems - Measurement of central wavelength, spectral width and additional spectral characteristics (IEC 61280-1-3:2021)

Relations

• Replaces: EN 61280-1-3:2010 - Fibre optic communication subsystem test procedures - Part 1-3: General communication subsystems - Central wavelength and spectral width measurement
• Effective Date: 31-Aug-2021

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN IEC 61280-1-3:2021
01-november-2021
Nadomešča:
SIST EN 61280-1-3:2010
Postopki preskušanja optičnega komunikacijskega podsistema - 1-3. del: Splošni
komunikacijski podsistemi - Merjenje osrednje valovne dolžine, spektralne širine
in dodatnih spektralnih značilnosti (IEC 61280-1-3:2021)
Fibre optic communication subsystem test procedures - Part 1-3: General
communication subsystems - Measurement of central wavelength, spectral width and
additional spectral characteristics (IEC 61280-1-3:2021)

Lichtwellenleiter-Kommunikationsuntersysteme - Grundlegende Prüfverfahren - Teil 1-3:

Prüfverfahren für allgemeine Kommunikationsuntersysteme - Messung von
Mittelwellenlänge und Spektralbreite (IEC 61280-1-3:2021)

Procédures d’essai des sous-systèmes de télécommunication à fibres optiques - Partie 1

-3: Sous-systèmes généraux de télécommunication - Mesure de la longueur d'onde

centrale, de la largeur spectrale et des caractéristiques spectrales supplémentaires (IEC

61280-1-3:2021)
Ta slovenski standard je istoveten z: EN IEC 61280-1-3:2021
ICS:
33.180.01 Sistemi z optičnimi vlakni na Fibre optic systems in
splošno general
SIST EN IEC 61280-1-3:2021 en

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

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SIST EN IEC 61280-1-3:2021
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SIST EN IEC 61280-1-3:2021
EUROPEAN STANDARD EN IEC 61280-1-3
NORME EUROPÉENNE
EUROPÄISCHE NORM
August 2021
ICS 33.180.01 Supersedes EN 61280-1-3:2010 and all of its
amendments and corrigenda (if any)
English Version
Fibre optic communication subsystem test procedures - Part 1-3:
General communication subsystems - Measurement of central
wavelength, spectral width and additional spectral characteristics
(IEC 61280-1-3:2021)

Procédures d'essai des sous-systèmes de Lichtwellenleiter-Kommunikationsuntersysteme -

télécommunication à fibres optiques - Partie 1-3: Sous- Grundlegende Prüfverfahren - Teil 1-3: Prüfverfahren für

systèmes généraux de télécommunication - Mesure de la allgemeine Kommunikationsuntersysteme - Messung von

longueur d'onde centrale, de la largeur spectrale et des Mittelwellenlänge und Spektralbreite

caractéristiques spectrales supplémentaires (IEC 61280-1-3:2021)
(IEC 61280-1-3:2021)

This European Standard was approved by CENELEC on 2021-08-09. 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 61280-1-3:2021 E
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SIST EN IEC 61280-1-3:2021
EN IEC 61280-1-3:2021 (E)
European foreword

The text of document 86C/1701/CDV, future edition 3 of IEC 61280-1-3, prepared by SC 86C “Fibre

optic systems and active devices” of IEC/TC 86 “Fibre optics” was submitted to the IEC-CENELEC

parallel vote and approved by CENELEC as EN IEC 61280-1-3:2021.
The following dates are fixed:

• latest date by which the document has to be implemented at national (dop) 2022–05–09

level by publication of an identical national standard or by endorsement

• latest date by which the national standards conflicting with the (dow) 2024–08–09

document have to be withdrawn

This document supersedes EN 61280-1-3:2010 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.

Any feedback and questions on this document should be directed to the users’ national committee. A

complete listing of these bodies can be found on the CENELEC website.
Endorsement notice

The text of the International Standard IEC 61280-1-3:2021 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 62522 NOTE Harmonized as EN 62522
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SIST EN IEC 61280-1-3:2021
EN IEC 61280-1-3:2021 (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 60825-1 - Safety of laser products - Part 1: EN 60825-1 -
Equipment classification and requirements
IEC 62129-1 - Calibration of wavelength/optical frequency EN 62129-1 -
measurement instruments - Part 1: Optical
spectrum analyzers
IEC 62129-2 - Calibration of wavelength/optical frequency EN 62129-2 -
measurement instruments - Part 2:
Michelson interferometer single
wavelength meters
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SIST EN IEC 61280-1-3:2021
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SIST EN IEC 61280-1-3:2021
IEC 61280-1-3
Edition 3.0 2021-07
INTERNATIONAL
STANDARD
colour
inside
Fibre optic communication subsystem test procedures –
Part 1-3: General communication subsystems – Measurement of central
wavelength, spectral width and additional spectral characteristics
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 33.180.01 ISBN 978-2-8322-9954-8

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

® Registered trademark of the International Electrotechnical Commission
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SIST EN IEC 61280-1-3:2021
– 2 – IEC 61280-1-3:2021 © IEC 2021
CONTENTS

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

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

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

3 Terms, definitions and abbreviated terms ........................................................................ 6

3.1 Wavelength ............................................................................................................. 6

3.2 Spectral width ......................................................................................................... 7

3.3 Additional spectral characteristics ........................................................................... 7

3.4 Abbreviated terms ................................................................................................... 8

4 Apparatus ........................................................................................................................ 8

4.1 Calibrated optical spectrum analyzer (OSA) ............................................................ 8

4.2 Calibrated optical wavelength meter (OWM) ........................................................... 8

4.3 Power supplies ....................................................................................................... 9

4.4 Input signal source or modulator ............................................................................. 9

4.5 Test cord ................................................................................................................ 9

5 Test sample ..................................................................................................................... 9

6 Procedure (method A) ..................................................................................................... 9

6.1 General ................................................................................................................... 9

6.2 Setup .................................................................................................................... 10

6.3 Adjustment of spectrum analyzer controls ............................................................. 10

6.4 Setting of optical wavelength meter....................................................................... 11

7 Procedure (method B) ................................................................................................... 11

7.1 Setup .................................................................................................................... 11

7.2 Adjustment of spectrum analyzer controls ............................................................. 11

7.3 Setting of optical wavelength meter....................................................................... 11

7.4 Continuous LED and SLM spectra ......................................................................... 12

7.5 Discrete MLM spectra ........................................................................................... 12

7.6 SLM spectra.......................................................................................................... 12

8 Calculation .................................................................................................................... 13

8.1 General ................................................................................................................. 13

8.2 Centre wavelength ................................................................................................ 13

8.2.1 Continuous LED spectra ................................................................................ 13

8.2.2 Discrete MLM spectra .................................................................................... 13

8.3 Centroidal wavelength .......................................................................................... 13

8.4 Peak wavelength ................................................................................................... 14

8.4.1 Continuous LED and SLM spectra ................................................................. 14

8.4.2 Discrete MLM spectra .................................................................................... 14

8.5 RMS spectral width (Δλ ) .................................................................................. 14

rms

8.6 n-dB-down spectral width (Δλ ) ........................................................................ 14

n-dB

8.7 Full-width at half-maximum spectral width (Δλ ) .............................................. 14

fwhm

8.7.1 Continuous LED spectra ................................................................................ 14

8.7.2 Discrete MLM spectra .................................................................................... 15

8.8 Side-mode suppression ratio (SMSR) ................................................................... 15

8.9 Signal-to-source spontaneous emission ratio (SSER) ........................................... 15

9 Test results ................................................................................................................... 15

9.1 Required information ............................................................................................. 15

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9.2 Information to be available on request .................................................................. 16

10 Examples of results ....................................................................................................... 16

Bibliography .......................................................................................................................... 21

Figure 1 – Example of a LED optical spectrum ...................................................................... 16

Figure 2 – Typical spectrum analyzer output for MLM laser ................................................... 18

Figure 3 – Δλ spectral width measurement for MLM laser.............................................. 18

fwhm

Figure 4 – Δλ spectral width calculation for MLM laser .................................................. 19

fwhm

Figure 5 – Peak emission wavelength and Δλ measurement for SLM laser ................... 19

30-dB

Figure 6 – Resolution bandwidth (RBW) dependence of SMSR for SLM laser ....................... 20

Figure 7 – Signal-to-source spontaneous emission ratio measurement for SLM laser ............ 20

Table 1 – Measurement points for LED spectrum from Figure 1 ............................................ 17

Table 2 – RMS spectral characterization ............................................................................... 17

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SIST EN IEC 61280-1-3:2021
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INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
FIBRE OPTIC COMMUNICATION SUBSYSTEM TEST PROCEDURES –
Part 1-3: General communication subsystems – Measurement of central
wavelength, spectral width and additional spectral characteristics
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.

IEC 61280-1-3 has been prepared by subcommittee 86C: Fibre optic systems and active

devices, of IEC technical committee 86: Fibre optics. It is an International Standard.

This third edition cancels and replaces the second edition published in 2010. This edition

constitutes a technical revision.

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

edition:

a) addition of measurement of signal-to-source spontaneous emission ratio in 8.9;

b) change of document title to reflect the additional measurement;

c) additional information on the resolution bandwidth used in the measurement of the side-

mode suppression ratio in 8.8;

d) use of a calibrated optical wavelength meter for accurate wavelength measurements of

single-longitudinal mode lasers.
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SIST EN IEC 61280-1-3:2021
IEC 61280-1-3:2021 © IEC 2021 – 5 –
The text of this International Standard is based on the following documents:
Draft Report on voting
86C/1701/CDV 86C/1717/RVC

Full information on the voting for its approval can be found in the report on voting indicated in

the above table.
The language used for the development of this International Standard is English.

This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in

accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement,

available at www.iec.ch/members_experts/refdocs. The main document types developed by

IEC are described in greater detail at www.iec.ch/standardsdev/publications.

A list of all parts in the IEC 61280 series, published under the general title Fibre optic

communication subsystem test 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 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 document 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 61280-1-3:2021
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FIBRE OPTIC COMMUNICATION SUBSYSTEM TEST PROCEDURES –
Part 1-3: General communication subsystems – Measurement of central
wavelength, spectral width and additional spectral characteristics
1 Scope

This part of IEC 61280 provides definitions and measurement procedures for several

wavelength and spectral width properties of an optical spectrum associated with a fibre optic

communication subsystem, an optical transmitter, or other light sources used in the operation

or test of communication subsystems. This document also provides definitions and

measurement procedures for side-mode suppression ratio and signal-to-source spontaneous

emission ratio.

The measurement is done for the purpose of system construction and/or maintenance. In the

case of communication subsystem signals, the optical transmitter is typically under

modulation.

NOTE Different properties can be appropriate to different spectral types, such as continuous spectra

characteristics of light-emitting diodes (LEDs), as well as multilongitudinal-mode (MLM), multitransverse-mode

(MTM) and single-longitudinal mode (SLM) spectra, which are characteristic of laser diodes (LDs).

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

IEC 62129-1, Calibration of wavelength/optical frequency measurement instruments – Part 1:

Optical spectrum analyzers

IEC 62129-2, Calibration of wavelength/optical frequency measurement instruments – Part 2:

Michelson interferometer single wavelength meters
3 Terms, definitions and abbreviated terms

For the purposes of this document, the following terms, definitions and abbreviated terms

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
3.1 Wavelength

NOTE The following wavelength terms provide quantitative definitions for the description of the central

wavelength of a spectrum. In this document, "central wavelength" is a general category label for these terms.

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IEC 61280-1-3:2021 © IEC 2021 – 7 –
3.1.1
centre wavelength

mean of the closest spaced half-power wavelengths in an optical spectrum, one above and

one below the peak wavelength
Note 1 to entry: Centre wavelength is also called “half-power mid-point”.
3.1.2
half-power wavelength
3dB
wavelength corresponding to a half-peak power value of the optical spectrum
3.1.3
peak wavelength
wavelength corresponding to the maximum power value of the optical spectrum
3.1.4
centroidal wavelength
mean or average wavelength of an optical spectrum
3.2 Spectral width
3.2.1
RMS spectral width
rms

square root of the second moment of the power distribution about the centroidal wavelength

3.2.2
n-dB-down spectral width
n-dB

positive difference of the closest spaced wavelengths, one above and one below the peak

wavelength λ , at which the spectral power density determined in a specified resolution

bandwidth is n dB down from its peak value
3.2.3
full-width at half-maximum
fwhm

positive difference of the closest spaced wavelengths, one above and one below the peak

, at which the spectral power density determined in a specified resolution
wavelength λ
bandwidth is 3 dB down from its peak value
3.3 Additional spectral characteristics
3.3.1
side-mode suppression ratio
SMSR

ratio of the largest peak of the optical spectrum to the second largest peak under non-

modulated (continuous wave) operating condition, which is determined in a specified

wavelength resolution bandwidth (RBW), for a nominally single-longitudinal mode (SLM)

spectrum
Note 1 to entry: See 8.8.
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3.3.2
signal-to-source spontaneous emission ratio
SSER

ratio between the signal power and maximum source spontaneous emission (SSE) power

under the non-modulated (CW) condition which is determined in a specified bandwidth

3.4 Abbreviated terms
CW continuous wave
DFB distributed feedback
ESD electrostatic discharge
InGaAsP indium gallium arsenide phosphide
LD laser diode
LED light-emitting diode
MLM multi-longitudinal mode
MTM multi-transverse mode
OSA optical spectrum analyzer
OWM optical wavelength meter
RBW resolution bandwidth
RMS root-mean-square
SLM single-longitudinal mode
SMSR side-mode suppression ratio
SSE source spontaneous emission
SSER signal-to-source spontaneous emission ratio
TLA tuneable laser assembly
VCSEL vertical cavity surface emitting lasers
WDM wavelength-division multiplexing
4 Apparatus
4.1 Calibrated optical spectrum analyzer (OSA)

This special-purpose test equipment uses a dispersive spectrophotometric method to resolve

and record the optical spectral distribution. The required wavelength resolution bandwidth and

range depend on the type and variety of signals to be measured. Generally, LED sources

have wide spectra with little structure, so a range of at least 200 nm and resolution bandwidth

of 1 nm or narrower are recommended. Laser sources have much narrower spectra and can

be used in wavelength-division multiplexing (WDM) applications, where more accurate

determination of the wavelength is required. A resolution bandwidth of 0,1 nm or narrower is

recommended, and the actual requirement is determined by the application. In any case, the

sensitivity and wavelength range of the spectrum analyzer shall be sufficient to measure all of

the spectrum within at least −20 dB from the peak power. For measurement of SMSR, a larger

dynamic range is typically required.

OSA equipment shall be calibrated for vacuum wavelengths in order to be consistent with the

calibration processes and results of IEC 62129-1. The equipment used shall have a valid

calibration certificate, in accordance with the applicable quality system for the period over

which the testing is done.
4.2 Calibrated optical wavelength meter (OWM)

For central wavelength measurements of SLM lasers, such as distributed feedback (DFB)

lasers or tuneable laser assemblies (TLAs) for dense WDM applications, sufficient

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IEC 61280-1-3:2021 © IEC 2021 – 9 –

measurement accuracy is required. In this case, an optical wavelength meter based on

interferometric spectroscopy can be used. The accuracy of the central wavelength

measurement is generally specified for non-modulated (CW) lasers. When the SLM laser is

modulated, the uncertainty of the central wavelength measurement increases with the

increasing modulation frequency or symbol rate.

OWM equipment shall be calibrated in accordance with IEC 62129-2. The equipment used

shall have a valid calibration certificate, in accordance with the applicable quality system for

the period over which the testing is done.
4.3 Power supplies
As required for the device under test.
4.4 Input signal source or modulator

The input signal source is a signal generator or modulator with the appropriate digital or

analogue signal of the system.
4.5 Test cord

Unless otherwise specified, the physical and optical properties of the test cords shall match

the cable plant with which the equipment is intended to operate. The cords shall be 2 m to

5 m long and shall contain fibres with coatings which remove cladding light. Appropriate

connectors shall be used. Single-mode cords shall be deployed with two 90 mm diameter

loops or otherwise assure rejection of cladding modes. If the equipment is intended for

multimode operation and the intended cable plant is unknown, the fibre size shall be

50/125 µm.
5 Test sample

The test sample shall be a specified fibre optic subsystem, transmitter, or light source. The

system inputs and outputs shall be those normally seen by the user. The spectral width

parameters are typically used for characterizing MLM and LED transmitters. The widths of

MTM and SLM lasers without modulation are normally too narrow to measure with the

dispersive spectral instruments used with this method. Modulated SLM transmitters have

broadened linewidths for high data rates (above about 2,5 Gb/s) caused by chirp that can be

measurable by this method.

Because of the potential for hazardous radiation, conditions of laser safety shall be

established and maintained. Refer to IEC 60825-1.
6 Procedure (method A)
6.1 General

Method A is designed for the use of typical commercial optical spectrum analyzer instruments

that allow quick measurement of spectra with 1 000 wavelength samples or more and allow

for the analysis of such spectra based on all of the samples, rather than selecting for example

only the samples
...