IEC 60793-1-43:2015

IEC 60793-1-43 ®
Edition 2.0 2015-03
INTERNATIONAL
STANDARD
colour
inside
Optical fibres –
Part 1–43: Measurement methods and test procedures– Numerical aperture
measurement
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IEC 60793-1-43 ®
Edition 2.0 2015-03
INTERNATIONAL
STANDARD
colour
inside
Optical fibres –
Part 1–43: Measurement methods and test procedures– Numerical aperture

measurement
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 33.180.10 ISBN 978-2-8322-2545-5

– 2 – IEC 60793-1-43:2015 © IEC 2015
CONTENTS
FOREWORD . 4
1 Scope . 6
2 Normative references. 6
3 Overview of method . 6
4 Reference test method . 7
5 Apparatus . 8
5.1 Input system . 8
5.1.1 Light source . 8
5.1.2 Input optics . 8
5.1.3 Fibre input end support and alignment . 8
5.1.4 Cladding mode stripper . 8
5.2 Output system and detection . 8
5.2.1 General . 8
5.2.2 Technique 1 – Angular scan (see Figure 2) . 9
5.2.3 Technique 2 – Angular scan (see Figure 3) . 10
5.2.4 Technique 3 – Scan of the spatial field pattern (see Figure 4) . 10
5.2.5 Technique 4 – Inverse far-field measurement (see Figure 5, applicable
to subcategory A4d fibres). 12
6 Sampling and specimens . 13
6.1 Specimen length . 13
6.2 Specimen endface . 13
7 Procedure . 13
8 Calculations . 13
8.1 Far-field versus maximum theoretical value . 13
8.2 Threshold intensity angle, θ . 14
k
8.3 Numerical aperture, NA . 14
ff
8.4 Calculating far-field intensity pattern when using Technique 3 . 15
8.5 Calculating NA when using Technique 4 . 15
9 Results . 15
9.1 Information available with each measurement . 15
9.2 Information available upon request . 16
10 Specification information . 16
Annex A (informative) Mapping NA measurement to alternative lengths . 17
A.1 Introductory remark . 17
A.2 Mapping long length NA measurement to short length NA measurement . 17
ff ff
Annex B (normative) Product specific default values for NA measurement . 18
B.1 Introductory remark . 18
B.2 Table of default values used in NA measurement for multimode products . 18

Figure 1 – Representative refractive index profile for a graded index multimode fibre . 7
Figure 2 – Technique 1 – Angular scan . 9
Figure 3 –Technique 2 – Angular scan . 10
Figure 4 – Technique 3 – Scan of the spatial field pattern . 11

Figure 5 – Technique 4 – Inverse far-field method . 13
Figure 6 – Example of a far-field NA measurement . 14
Figure 7 – Sample output of an A4d fibre measured using Technique 4 . 15

Table B.1 – Default values for parameters used in the far-field NA measurement of
multimode fibres . 18

– 4 – IEC 60793-1-43:2015 © IEC 2015
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
OPTICAL FIBRES –
Part 1–43: Measurement methods and test procedures–
Numerical aperture measurement

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
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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 60793-1-43 has been prepared by subcommittee 86A: Fibres and
cables, of IEC technical committee 86: Fibre optics.
This second edition cancels and replaces the first edition published in 2001, and constitutes a
technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
– expansion of the scope to include A1, A2, A3 and A4 multimode fibre categories;
– addition of measurement parameters of sample length and threshold values, product
specific to the variables that are now found in the product specifications;
– a new Annex B entitled "Product specific default values for NA measurement";
– addition of a new Technique 4 for measuring NA of A4d fibres;

– a new Annex A entitled "Mapping NA measurement to alternative lengths" that gives a
mapping function to correlate shorter sample length measurements to the length
suggested in the reference test method Na .
ff
This International Standard is to be used in conjunction with IEC 60793-1-1, IEC 60793-1-21
and IEC 60793-1-22.
The text of this standard is based on the following documents:
CDV Report on voting
86A/1566/CDV 86A/1622/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.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts in the IEC 60793 series, published under the general title Optical fibres, can
be found on the IEC website.
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC website 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.

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