IEC 61280-1-3:2010

IEC 61280-1-3 ®
Edition 2.0 2010-03
INTERNATIONAL
STANDARD
Fibre optic communication subsystem test procedures –
Part 1-3: General communication subsystems – Central wavelength and spectral
width measurement
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IEC 61280-1-3 ®
Edition 2.0 2010-03
INTERNATIONAL
STANDARD
Fibre optic communication subsystem test procedures –
Part 1-3: General communication subsystems – Central wavelength and spectral
width measurement
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
Q
ICS 33.180.01 ISBN 978-2-88910-472-7
– 2 – 61280-1-3 © IEC:2010(E)
CONTENTS
FOREWORD.3

1 Scope.5

2 Normative references .5

3 Terms and definitions .5

3.1 Wavelength .5

3.2 Spectral width .6

3.3 Additional spectral characteristics .6

4 Apparatus.6
4.1 Calibrated optical spectrum analyzer .6
4.2 Power supplies.7
4.3 Input signal source or modulator .7
4.4 Test cord.7
5 Test sample.7
6 Procedure (Method A) .7
6.1 General .7
6.2 Setup .7
6.3 Adjustment of spectrum analyzer controls .8
7 Procedure (Method B) .8
7.1 Setup .8
7.2 Adjustment of spectrum analyzer controls .9
7.3 Continuous LED and SLM spectra .9
7.4 Discrete MLM spectra.9
7.5 Continuous SLM spectra .10
8 Calculation .10
8.1 General .10
8.2 Centre wavelength .10
8.3 Centroidal wavelength .10
8.4 Peak wavelength .11
8.5 RMS spectral width (Δλ ) .11
rms
8.6 n-dB spectral width (Δλ ) .11
n-dB
8.7 Full-width half-maximum spectral width (Δλ ).11
fwhm
8.8 Side-mode suppression ratio (SMSR) .12

9 Test results .12
9.1 Required information .12
9.2 Information to be available on request.12
10 Example results.12
Figure 1 – Example of a LED optical spectrum.13
Figure 2 – Typical spectrum analyzer output for an MLM laser.15
Figure 3 – Δλ spectral width measurement for MLM laser .16
fwhm
Figure 4 – Δλ spectral width calculation for MLM laser.16
fwhm
Figure 5 – Peak emission wavelength and Δλ measurement for SLM laser.17
30–dB
Table 1 – Measurement points for LED spectrum from Figure 1 .13
Table 2 – RMS spectral characterization.14

61280-1-3 © IEC:2010(E) – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION

___________
FIBRE OPTIC COMMUNICATION
SUBSYSTEM TEST PROCEDURES –
Part 1-3: General communication subsystems –

Central wavelength and spectral width measurement

FOREWORD
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
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patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 61280-1-3 has been prepared by subcommittee 86C: Fibre optic
systems and active devices, of IEC technical committee 86.
This second edition cancels and replaces the first edition published in 1998. This edition
constitutes a technical revision with changes reflecting new laser technology and includes a
second method modified for state of the art instrumentation.
The text of this standard is based on the following documents:
CDV Report on voting
86C/ 887/CDV 86C/ 937/RVC
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.

– 4 – 61280-1-3 © IEC:2010(E)
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.

A list of all parts of the IEC 61280 series can be found, under the general title Fibre optic

communication subsystem test procedures, on the IEC website.

The committee has decided that the contents of this amendment and the base publication will

remain unchanged until the stability date indicated on the IEC web site under

"http://webstore.iec.ch" in the data related to the specific publication. At this date, the

publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
A bilingual version of this publication may be issued at a later date.

61280-1-3 © IEC:2010(E) – 5 –
FIBRE OPTIC COMMUNICATION
SUBSYSTEM TEST PROCEDURES –
Part 1-3: General communication subsystems –

Central wavelength and spectral width measurement

1 Scope
This part of IEC 61280 provides definitions and measure 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.
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).
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 60825-1, Safety of laser products – Part 1: Equipment classification and requirements
IEC 62129, Calibration of optical spectrum analyzers
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply
...