IEC 63267-3-61:2025

IEC 63267-3-61 ®
Edition 1.0 2025-06
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Fibre optic interconnecting devices and passive components - Fibre optic
connector optical interfaces for enhanced macrobend multimode fibres -
Part 3-61: Connector parameters of physically contacting 50 μm core diameter
fibres - Non-angled 2,5 mm and 1,25 mm diameter cylindrical full zirconia
ferrules for reference connection applications

Dispositifs d'interconnexion et composants passifs fibroniques - Interfaces
optiques des connecteurs fibroniques pour fibres multimodales améliorées en
macrocourbures -
Partie 3-61: Paramètres de connexion des fibres d’un diamètre de cœur de 50
μm en contact physique - Férules cylindriques non inclinées en zircone plein de
2,5 mm et 1,25 mm de diamètre, pour les applications de connexion de référence
ICS 33.180.20  ISBN 978-2-8327-0505-6

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CONTENTS
FOREWORD . 2
1 Scope . 4
2 Normative references . 4
3 Terms and definitions . 4
4 Attenuation grade . 5
5 Description . 5
6 Criteria for a fit within the reference performance grade . 6
6.1 Geometry of reference plug after termination . 6
6.2 Use of selected fibre in reference-grade connectors . 8
7 Reference adapter . 9
Annex A (informative) Attenuation test limits of reference grade R connectors to
m1
grade B connectors . 10
m
A.1 General . 10
A.2 Performance grade B test limit against R reference connector . 10
m m1
A.3 Calculated attenuation of random mated Grade R reference connections . 10
m1
Annex B (normative) Maximum allowed spherical fibre undercut . 12
Bibliography . 14

Figure 1 – Geometrical requirements for fibre core location after termination relative to
the ferrule axis and the connector plug key . 6
Figure 2 – Interface dimensions for PC ferrule . 7
Figure A.1 – Calculated attenuation of random mated Grade R reference connectors . 11
m1
Figure B.1 – Allowable undercut as a function of endface radius and apex offset –
4,9 N minimum contact force . 13
Figure B.2 – Allowable undercut as a function of end face radius and apex offset –
2,9 N minimum contact force . 13

Table 1 – Multimode attenuation grade at 850 nm . 5
Table 2 – Optical interface parameter values for 2,5 mm diameter PC ferrules for
multimode reference connectors grade R . 8
m1
Table 3 – Optical interface parameter values for 1,25 mm diameter PC ferrules for
multimode reference connectors grade R . 8
m1
Table A.1 – Performance grade test limits at 850 nm . 10

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
Fibre optic interconnecting devices and passive components - Fibre optic
connector optical interfaces for enhanced macrobend multimode fibres -
Part 3-61: Connector parameters of physically contacting 50 μm core
diameter fibres - Non-angled 2,5 mm and 1,25 mm diameter cylindrical
full zirconia ferrules for reference connection applications

FOREWORD
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IEC 63267-3-61 has been prepared by subcommittee 86B: Fibre optic interconnecting devices
and passive components, of IEC technical committee 86: Fibre optics. It is an International
Standard.
This first edition and the first edition of IEC 63267-2-2 cancel and replace the first edition of
IEC 61755-6-2 published in 2018. This edition constitutes a technical revision. The document
includes the following significant technical changes with respect to the previous edition:
a) Definition of a reference grade, R interface;
m1
b) Inclusion of A1-OM2b to A1-OM5b fibres;
c) Updates to normative references;
d) The addition of Annex A, which describes the attenuation test limits of reference grade R
m1
connectors to grade B connectors;
m
e) A new Annex B that describes the allowable fibre undercut.
The text of this International Standard is based on the following documents:
Draft Report on voting
86B/5030/FDIS 86B/5075/RVD
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.
A list of all parts in the IEC 63267-3-61 series, published under the general title Fibre optic
interconnecting devices and passive components – Fibre optic connector optical
...