IEC 63267-3-81:2025

Fibre optic interconnecting devices and passive components - Connector optical interfaces for enhanced macro bend multimode fibre - Part 3-81: Connector parameters of physically contacting 50 μm core diameter fibres - Non-angled polyphenylene sulphide rectangular ferrules with a single row of 12, 8, 4, or 2 fibres for reference connector applications

IEC 63267-3-81: 2025 defines the dimensional limits of an optical interface for reference connectors with rectangular ferrules necessary to meet specific requirements for fibre-to-fibre interconnection of non-angled polished multimode reference connectors with rectangular ferrules intended to be used for attenuation measurements as defined in IEC 63267‑2‑2. Ferrule dimensions and features are contained in the IEC 61754 series of fibre optic interface standards.One grade of reference connector is defined in this document. The reference connector is terminated to restricted IEC 60793-2-10 A1-OM2b to A1-OM5b fibre at 850 nm band only. The geometrical dimensions and tolerances of the specified reference connector have been developed primarily to limit the variation in measured attenuation between multiple sets of two reference connectors, and therefore to limit the variation in measured attenuation between randomly chosen reference connectors when mated with connectors in the field or factory.

Dispositifs d’interconnexion et composants passifs fibroniques - Interfaces optiques des connecteurs pour fibres multimodales améliorées en macrocourbures - Partie 3-81: Paramètres de connexion des fibres d’un diamètre de coeur de 50 μm en contact physique - Ferrules rectangulaires non inclinées en polysulfure de phénylène avec une seule rangée de 12, 8, 4 ou 2 fibres, pour les applications de connecteurs de reference

IEC 63267-3-81: définit les limites dimensionnelles d’une interface optique pour les connecteurs de référence à ferrule rectangulaire, qui sont nécessaires pour satisfaire aux exigences particulières des interconnexions fibre à fibre des connecteurs de référence multimodaux polis non inclinés à ferrule rectangulaire, destinés à être utilisés pour les mesures d’affaiblissement telles qu’elles sont définies dans l’IEC 63267-2-2. Les dimensions et les caractéristiques des ferrules sont spécifiées dans les normes d’interfaces fibroniques de la série IEC 61754. Le présent document définit une classe de connecteur de référence. Le connecteur de référence est raccordé à une sélection de fibres conformes à l’IEC 60793-2-10, soit les fibres des sous-catégories A1-OM2b à A1-OM5b, et uniquement dans la bande de 850 nm. Les dimensions géométriques et les tolérances du connecteur de référence spécifié ont été développées principalement pour limiter les écarts au niveau de l’affaiblissement mesuré entre les différentes paires de connecteurs de référence, et donc pour limiter les écarts au niveau de l’affaiblissement mesuré entre des connecteurs de référence choisis de manière aléatoire, lorsqu’ils sont accouplés à des connecteurs sur le terrain ou en usine.

General Information

• Status: Published
• Publication Date: 24-Jun-2025
• ICS: 33.180.20 - Fibre optic interconnecting devices
• Technical Committee: SC 86B - Fibre optic interconnecting devices and passive components
• Current Stage: PPUB - Publication issued
• Start Date: 25-Jun-2025
• Completion Date: 04-Jul-2025

Overview

IEC 63267-3-81:2025 is an international standard published by the International Electrotechnical Commission (IEC) that defines the dimensional limits and connector parameters for fibre optic interconnecting devices and passive components. Specifically, it covers connector optical interfaces for enhanced macro bend multimode fibres with a 50 μm core diameter. This part of the IEC 63267 series focuses on non-angled polyphenylene sulphide rectangular ferrules housing a single row of fibres, available with 2, 4, 8, or 12 fibres, intended for reference connector applications such as attenuation measurements.

This standard establishes requirements necessary for fibre-to-fibre interconnection of non-angled polished multimode reference connectors terminated on restricted multimode fibre types (IEC 60793-2-10 A1-OM2b to A1-OM5b) operating in the 850 nm wavelength band. The goal is to ensure consistent, repeatable attenuation measurements by limiting geometrical variation between reference connectors, thereby reducing variability in field or factory connector performance testing.

Key Topics

• Rectangular Ferrule Specifications: Details ferrule dimensions and physical contact parameters for variants with 2, 4, 8, or 12 fibres aligned in a single row with a nominal 0.25 mm fibre pitch.
• Reference Connector Interface Variants: Defines four primary variants (R₂, R₄, R₈, R₁₂) each specifying exact ferrule cross-sections and fibre counts.
• Dimensional Limits and Tolerances: Provides precise interface geometry requirements to ensure consistent fibre alignment, lateral and angular offset limits, and physical contact endface geometries.
• Attenuation Measurement Consistency: Specifies attenuation grades and performance requirements to minimize variability in optical loss measurements when mating connectors.
• Normative References: Cites related standards such as IEC 61754 series for ferrule dimensions and IEC 60793-2-10 for multimode fibre specifications.
• Fibre Numbering and Alignment Conventions: Illustrates fibre numbering system and ferrule cross-sectional layout to standardize connector manufacturing and testing processes.

Applications

IEC 63267-3-81:2025 is critical for:

• Fibre Optic Reference Connectors: Used in factory and field environments for calibration and attenuation measurement of multimode fibre optic links.
• Telecommunications and Data Centers: Ensures reliable and repeatable interconnection performance for multimode fibre networks operating at 850 nm wavelengths.
• Quality Assurance and Testing Laboratories: Provides standardized connector interfaces that limit measurement differences between equipment sets and operators.
• Multimode Fibre Component Manufacturers: Guides design and manufacturing of rectangular ferrule connectors with strict dimensional controls for enhanced macro bend fibres.
• Passive Optical Network Deployments: Supports the deployment of bend-insensitive multimode fibre connectors with improved measurement accuracy.

By adhering to this standard, manufacturers and network operators can achieve interoperability, optimize performance testing, and maintain high-quality fibre optic connections essential for modern high-speed networks.

Related Standards

To fully implement IEC 63267-3-81:2025, the following related IEC standards are essential references:

• IEC 63267-2-2: Defines attenuation measurement methods for fibre optic reference connectors.
• IEC 61754 Series: Covers detailed ferrule dimensions and connector interface specifications for fibre optic connectors including rectangular ferrules.
• IEC 60793-2-10: Product specifications for multimode optical fibres, including bend-insensitive fibre grades covered in this standard.
• IEC 61300 Series: Provides basic test and measurement procedures, including attenuation, hole location, and endface geometry measurements for fibre optic connectors.
• IEC 63267-1: Gives general guidance on enhanced macro bend loss multimode 50 μm core diameter fibres and connector optical interfaces.

Together, these standards form a comprehensive framework for designing, manufacturing, testing, and applying multimode fibre optic connectors with enhanced reliability, precision, and performance.

---

Keywords: IEC 63267-3-81:2025, fibre optic connectors, multimode fibre, enhanced macro bend fibre, rectangular ferrules, physical contact connector, optical interface, fibre optic standards, attenuation measurement, IEC fibre connectors, 50 μm core optical fibre, reference connectors, fibre optic interconnection.

Standards Content (Sample)

IEC 63267-3-81 ®
Edition 1.0 2025-06
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Fibre optic interconnecting devices and passive components - Connector optical
interfaces for enhanced Macro bend multimode fibre -
Part 3-81: Connector parameters of physically contacting 50 μm core diameter
fibres - Non-angled polyphenylene sulphide rectangular ferrules with a single
row of 12, 8, 4, or 2 fibres for reference connector applications

Dispositifs d’interconnexion et composants passifs fibroniques - Interfaces
optiques des connecteurs pour fibres multimodales améliorées en
macrocourbures -
Partie 3-81: Paramètres de connexion des fibres d’un diamètre de cœur de 50
µm en contact physique - Ferrules rectangulaires non inclinées en polysulfure
de phénylène avec une seule rangée de 12, 8, 4 ou 2 fibres, pour les applications
de connecteurs de référence
ICS 33.180.20  ISBN 978-2-8327-0504-9

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CONTENTS
FOREWORD . 2
1 Scope . 4
2 Normative references . 4
3 Terms and definitions . 5
4 Reference grade variants and fibre numbering conventions . 5
5 Attenuation grade . 6
6 Description . 6
7 Reference interface parameters . 7
7.1 Geometry of reference plug after termination . 7
7.2 Use of selected fibre in multimode reference-grade connectors . 14
Annex A (informative) Attenuation test limit of reference connectors mated to grade
B connectors . 15
m
A.1 General . 15
A.2 Performance grade B test limit against reference connectors . 15
m
A.3 Attenuation grade of reference connectors . 15
Bibliography . 17

Figure 1 – Fibre numbering conventions . 5
Figure 2 – Interface dimensions related to lateral and angular offset . 8
Figure 3 – Alignment pin . 8
Figure 4 – Interface dimensions related to longitudinal offset (physical contact) . 10
Figure A.1 – Calculated attenuation of random mated Grade R reference
m12
connectors . 16

Table 1 – Reference connector optical interface variant information . 5
Table 2 – Multimode reference attenuation grade at 850 nm . 6
Table 3 – Optical interface dimensions related to lateral and angular offset for optical
interface variant R . 9
m2
Table 4 – Optical interface dimensions related to lateral and angular offset for optical
interface variants R , R , and R . 9
m12 m8 m4
Table 5 – Optical interface end face geometry dimensions related to physical contact
for optical interface variant R . 11
m2
Table 6 – Optical interface end face geometry dimensions related to physical contact
for optical interface variant R . 12
m4
Table 7 – Optical interface end face geometry dimensions related to physical contact
for optical interface variant R . 13
m8
Table 8 – Optical interface end face geometry dimensions related to physical contact
for optical interface variant R . 14
m12
Table A.1 – Performance grade test limits at 850 nm . 15

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
Fibre optic interconnecting devices and passive components - Connector
optical interfaces for enhanced macro bend multimode fibre -
Part 3-81: Connector parameters of physically contacting 50 μm core
diameter fibres - Non-angled polyphenylene sulphide rectangular ferrules
with a single row of 12, 8, 4, or 2 fibres for reference connector
applications
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
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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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9) IEC draws attention to the possibility that the implementation of this document may involve the use of (a)
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the latest information, which may be obtained from the patent database available at https://patents.iec.ch. IEC
shall not be held responsible for identifying any or all such patent rights.
IEC 63267-3-81 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.
The text of this International Standard is based on the following documents:
Draft Report on voting
86B/5037/FDIS 86B/5076/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 series, published under the general title Fibre optic
interconnecting devices and passive components – Connector optical interfaces for enhanced
macro bend multimode fibre, can be found on the IEC website.
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/publications.
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, or
• revised.
1 Scope
This part of the IEC 63267 series defines the dimensional limits of an optical interface for
reference connectors with rectangular ferrules necessary to meet specific requirements for
fibre-to-fibre interconnection of non-angled polished multimode reference connectors with
rectangular ferrules intended to be used for attenuation measurements as defined in
IEC 63267-2-2.
Ferrule dimensions and features are contained in the IEC 61754 series of fibre optic interface
standards.
One grade of reference connector is defined in this document. The reference connector is
terminated to restricted IEC 60793-2-10 A1-OM2b to A1-OM5b fibre at 850 nm band only.
The geometrical dimensions and tolerances of the specified reference connector have been
developed primarily to limit the variation in measured attenuation between multiple sets of two
reference connectors, and therefore to limit the variation in measured attenuation between
randomly chosen reference connectors when mated with connectors in the field or factory.
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 60793-2-10, Optical fibres – Part 2-10: Product specifications – Sectional specification for
category A1 multimode fibres
IEC 61300-3-4, Fibre optic interconnecting devices and passive components – Basic test and
measurement procedures – Part 3-4: Examinations and measurements – Attenuation
IEC 61300-3-27, Fibre optic interconnecting devices and passive components – Basic test and
measurement procedures – Part 3-27: Examinations and measurements –Measurement method
for the hole location of a multiway connector plug
IEC 61300-3-30, Fibre optic interconnecting devices and passive components – Basic test and
measurement procedures – Part 3-30: Examinations and measurements – Endface geometry
of rectangular ferrule
IEC 61754-5:2005, Fibre optic connector interfaces – Part 5: Type MT connector family
IEC 61754-7-1:2014, Fibre optic interconnecting devices and passive components – Fibre optic
connector interfaces – Part 7-1: Type MPO connector family – One fibre row
IEC 61754-18:2001, Fibre optic connector interfaces – Part 18: Type MT-RJ connector family
IEC 63267-1, Fibre optic interconnecting devices and passive components – Fibre optic
connector optical interfaces – Part 1: Enhanced macro bend loss multimode 50 µm core
diameter fibres – General and guidance
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 63267-1 apply.
ISO and IEC maintain terminology databases for use in standardization at the following
addresses:
• IEC Electropedia: available at https://www.electropedia.org/
• ISO Online browsing platform: available at https://www.iso.org/obp
4 Reference grade variants and fibre numbering conventions
This document defines the dimensional limits of physical contact non-angled (PC) rectangular
ferrules with a single row up to twelve fibres. The fibre centres are spaced with a nominal
alignment pitch of 0,25 mm. Interface variants, which identify nominal ferrule cross-sections
and applicable fibre counts are given in Table 1. The fibre numbering conventions are illustrated
in Figure 1.
Table 1 – Reference connector optical interface variant information
a
Reference connector variant Number of fibres
Nominal ferrule cross section
(mm × mm)
R
2,45 × 4,4 2
m2
R
2,45 × 6,4 4
m4
R
2,45 × 6,4 8
m8
R
2,45 × 6,4 12
m12
a
Refer to the applicable IEC 61754 series fibre optic connector interface standard for dimensional requirements.

Figure 1 – Fibre numbering conventions
5 Attenuation grade
The performance grade for PC polished reference connectors detailed in this document is
shown in Table 2.
The specified attenuation for the grade is obtained when the reference plug (e.g. pinned) is
connected to other rectangular reference plugs (unpinned) using the specified geometrical
tolerances in Clause 7, and the attenuation is measured in accordance with IEC 61300-3-4
(insertion method B).
Table 2 – Multimode reference attenuation grade at 850 nm
Reference grade Attenuation Contribution to
a
measurement uncertainty
(dB)
(dB)
R
m2
R
m4
≤ 0,15 ± 0,071
R
m8
R
m12
NOTE The maximum attenuation of reference grade connections mated to standard
grade connections is described in Annex A.
a
As described in IEC 63267-2-2, related to the measurement of the attenuation
between any connector according the IEC optical interface standards and a
population of reference connectors

This document currently only specifies one attenuation grade, however, the construction of the
document allows inclusion for other grades in the future, if necessary.
6 Description
Optical reference connectors are connectors manufactured with restricted tolerances on
dimensions that contribute to lateral and angular offset of such optical connections. These
connectors are mainly used for attenuation measurement purposes and shall be considered as
part of the measurement setup. The goal is to strongly reduce the measurement uncertainty.
The attenuation uncertainties due to the reference connectors are defined in IEC 63267-2-2.
The performance of a multimode optical interface is not only determined by the alignment
accuracy of the optical datum targets of two mating fibres, but also by any fibre parameter
mismatches. There are three conditions affecting the alignment of two optical datum targets:
lateral offset, angular offset and longitudinal offset.
Parameters influencing the lateral and angular offset of the optical fibre axes in rectangular
ferrules include:
• guide pin hole diameter;
• guide pin diameter;
• pitch dimension of guide pin holes;
• fibre hole true position (TP);
• fibre hole angle relative to reference plane through the guide pins;
• fibre cladding diameter to fibre hole inner diameter;
• fibre core true position relative to the fibre cladding diameter.
Parameters influencing the fibre-to-fibre intrinsic attenuation include:
• core diameter (CD) mismatch;
• numerical aperture (NA) mismatch;
• core non-circularity;
• alpha profile mismatch;
• refractive index mismatch.
The core non-circularity, alpha profile mismatch and refractive index mismatch parameters are
not considered in the development of this document.
Parameters that govern and control the physical contact of two mated connectors include:
• fibre height;
• ferrule X angle;
• ferrule Y angle;
• minus coplanarity;
• fibre tip radius / core dip;
• axial force on ferrule end face;
• ferrule and fibre material physical constraints.
7 Reference interface parameters
7.1 Geometry of reference plug after termination
Optical interface dimensions related to lateral and angular offset are defined in Figure 2 and
the alignment pin geometry is shown in Figure 3. The end face geometry parameters that
influence longitudinal offset are outlined in Figure 4. The parameter values related to lateral
and angular offset are given in Table 3 and Table 4. End face geometry limits associated with
longitudinal offset are specified in Table 5 to Table 8. All multimode reference connectors shall
be terminated on restricted multimode (MM) A1-OM2b to A1-OM5b, as specified in
IEC 60793-2-10 and Subclause 7.2.
Key
A Fibre core positional tolerance (TP) that applies to all fibres
B Guide pin hole pitch
C Tilt angle of fibre axis
D Guide pin hole diameter
E Parallelism tolerance of guide pin hole two (V) with respect to guide pin hole one (U)
U Datum axis established by guide pin hole one
V Datum axis established by guide pin hole two
X Axis established by a line passing through two guide pin hole centres
Y Axis established by a line orthogonal to the X-axis and passing through the midpoint of the line connecting the
two guide pin hole centres
Z Axis established as the average of the two guide pin hole axes (based on a hole depth of 3,3 mm) and orthogonal
to the X-axis and Y-axis.
NOTE 1 For simplification of the drawing, only a four-position version is shown.
NOTE 2 The basic X-location, X , for each fibre core centre is define as:
i
X = (2i – n – 1) 0,125
i
th
Where, i corresponds to the i fibre per the numbering convention outlined in Figure 1 and n is the total number of
fibres in the array.
Figure 2 – Interface dimensions related to lateral and angular offset

Key
G Surface roughness over length, L.
J Guide pin diameter
K Cylindricity
Figure 3 – Alignment pin
The parameter values given in Table 3 and Table 4 shall be met by an individual reference
interface after termination to ensure that the specified random attenuation performance grade
with other reference plugs will be met. The specified maximum random performance is based
on a uniform distribution of the restricted core diameter and numerical aperture.
Table 3 – Optical interface dimensions related to lateral
and angular offset for optical interface variant R
m2
Parameter values
Reference Unit Remarks
Minimum Maximum
a
0 0,001 6 mm
A
B 2,598 2,602 mm Guide pin hole pitch
C - 0,2 Fibre angle error
°
b
D 0,699 0 0,699 6 mm Diameter
c
- 0,012 mm Hole parallelism
E
G - 200 nm RMS roughness
J 0,698 4 0,698 6 mm Diameter
K - 0,000 5 mm Cylindricity
a
True position of multimode core measured according to IEC 61300-3-27. The core location (A) values specified
are met under all
in this document have been calculated to ensure that the attenuation values for Grade R
m2
circumstances. It is assumed that fibre angle (C) is less or equal than 0,2 degree.
b
Each guide-hole shall accept a gauge pin as shown in Figure 1c of IEC 61754-18:2001 to a depth of 5,5 mm
with a maximum force of 1,7 N. In addition, two guide-holes shall accept a gauge as shown in Figure 1d of
IEC 61754-18:2001 to a depth of 5,5 mm with a maximum force of 3,4 N.
c
Parallelism tolerance applies over a hole depth of 3,3 mm. Refer to IEC 61300-3-30.

Table 4 – Optical interface dimensions related to lateral and
angular offset for optical interface variants R , R , and R
m12 m8 m4
Parameter values
Reference Unit Remarks
Minimum Maximum
a
0 0,001 6 mm
A
B 4,598 4,602 mm Guide pin hole pitch
C - 0,2 ° Fibre angle error
b
0,699 0 0,699 6 mm Diameter
D
c
- 0,012 mm Hole parallelism
E
G - 200 nm RMS roughness
J 0,698 4 0,698 6 mm Diameter
K - 0,000 5 mm Cylindricity
a
True position of multimode core measured according to IEC 61300-3-27. The core location (A) values specified
in this document have been calculated to ensure that the attenuation values for Grades R , R , and R
m12 m8 m4
are met under all circumstances. It is assumed that fibre angle (C) is less or equal than 0,2 degree.
b
Each guide-hole shall accept a gauge pin as shown in Figure 2 of IEC 61754-5:2005 and Figure 5 of
IEC 61754-7-1:2014 to a depth of 5,5 mm with a maximum force of 1,7 N. In addition, two guide-holes shall
accept a gauge for plug as shown in Figure 6 of IEC 61754-5:2005 and Figure 6 of IEC 61754-7-1:2014 to a
depth of 5,5 mm with a maximum force of 3,4 N.
c
Parallelism tolerance applies over a hole depth of 3,3 mm. Refer to IEC 61300-3-30.

Key
CDP Core dip
CF Minus coplanarity
H Fibre height
HA Adjacent fibre height differential
RF Fibre tip spherical radius (for the case of no core dip)
RX Ferrule surface x-radius
RY Ferrule surface y-radius
SX Ferrule surface x-angle
SY Ferrule surface y-angle
X Axis established by a line passing through two guide pin hole centres
Y Axis established by a line orthogonal to the X-axis and passing through the midpoint of the line connecting
the two guide pin hole centres
Z Axis established as the average of the two guide pin hole axes (based on a hole depth of 3,3 mm) and
orthogonal to the X-axis and Y-axis.
NOTE 1 For simplification of the drawing, only a four-position version is shown.
NOTE 2 All parameters are illustrated as positive values with respect to the defined coordinate system. Concave
ferrule radii are indicated by negative values.
Figure 4 – Interface dimensions related to longitudinal offset (physical contact)
Table 5 – Optical interface end face geometry dimensions
related to physical contact for optical interface variant R
m2
Parameter values
Reference Unit Remarks
Minimum Maximum
SX -0,15 0,15 ° Ferrule surface x-angle
SY -0,2 0,2 ° Ferrule surface y-angle
H 1 3,5 μm Fibre height
HA 0 0,3 μm Adjacent fibre height differential
RF 1 - mm Fibre tip spherical radius
2 000 (convex)
RX - mm Ferrule surface x-radius
-10 000 (concave)
RY 5 - mm Ferrule surface y-radius
CDP 120 nm Core dip
NOTE 1 End face parameter requirements apply to performance grade R .
m2
NOTE 2 Refer to Figure 4 for dimensional references.
NOTE 3 End face geometry to be measured in accordance with IEC 61300-3-30.
NOTE 4 The values in Table 5 are specified in the region of interest (ROI) of 0,900 × 0,675 mm (L × H) as defined
in IEC 61300-3-30 for variant number 1002.
NOTE 5 The values in Table 5 apply for polyphenylene sulphide (PPS) ferrules with a Young’s modulus of 15 GPa
to 20 GPa. Ferrule compression force: 7,8 N minimum and 11,8 N maximum.

Table 6 – Optical interface end face geometry dimensions related
to physical contact for optical interface variant R
m4
Parameter values
Reference Unit Remarks
Minimum Maximum
b
CF - Minus coplanarity
0,4 µm
SX -0,15 0,15 ° Ferrule surface x-angle
SY -0,2 0,2 ° Ferrule surface y-angle

H 1 3,5 Fibre height
µm
HA 0 0,3 µm Adjacent fibre height differential
RF 1 - mm Fibre tip spherical radius
2 000 (convex)
RX - mm Ferrule surface x-radius
-10 000 (concave)
RY 5 - mm Ferrule surface y-radius
CDP - 120 nm Core dip
a
GL - 22,6
NOTE 1 End face parameter requirements apply to performance grade R .
m4
NOTE 2 Refer to Figure 4 for dimensional references.
NOTE 3 End face geometry to be measured in accordance with IEC 61300-3-30.
NOTE 4 The values in Table 6 are specified in the region of interest (ROI) of 2,900 × 0,675 mm (L × H) as defined
in IEC 61300-3-30 for variant number 1004.
NOTE 5 The values in Table 6 apply for polyphenylene sulphide (PPS) ferrules with a Young’s modulus of 15 GPa
to 20 GPa. Ferrule compression force: 7,8 N minimum and 11,8 N maximum.
a
See IEC 61300-3-30 for description and determination of GL. This parameter is only calculated when ≤ 50 % of
the fibres have core dip.
b
The maximum allowable minus coplanarity, CF, shall be reduced to 0,15 µm when ≥ 50 % of the fibres have core
dip.
Table 7 – Optical interface end face geometry dimensions
related to physical contact for optical interface variant R
m8
Parameter values
Reference Unit Remarks
Minimum Maximum
b
CF - μm Minus coplanarity
0,4
SX -0,15 0,15 ° Ferrule surface x-angle
SY -0,2 0,2 ° Ferrule surface y-angle
H 1 3,5 μm Fibre height
HA 0 0,3 μm Adjacent fibre height differential
RF 1 - mm Fibre tip spherical radius
2 000 (convex)
RX - mm Ferrule surface x-radius
-10 000 (concave)
RY 5 - mm Ferrule surface y-radius
CDP - 120 nm Core dip
a
- 17,9
GL
NOTE 1 End face parameter requirements apply to performance grade R .
m8
NOTE 2 Refer to Figure 4 for dimensional references.
NOTE 3 End face geometry to be measured in accordance with IEC 61300-3-30.
NOTE 4 The values in Table 7 are specified in the region of interest (ROI) of 2,900 × 0,675 mm (L × H) as defined
in IEC 61300-3-30 for variant number 1008.
NOTE 5 The values in Table 7 apply for polyphenylene sulphide (PPS) ferrules with a Young’s modulus of 15 GPa
to 20 GPa. Ferrule compression force: 7,8 N minimum and 11,8 N maximum.
a
See IEC 61300-3-30 for description and determination of GL. This parameter is only calculated when ≤ 50 % of
the fibres have core dip.
b
The maximum allowable minus coplanarity, CF, shall be reduced to 0,15 µm when ≥ 50 % of the fibres have core
dip.
Table 8 – Optical interface end face geometry dimensions
related to physical contact for optical interface variant R
m12
Parameter values
Reference Unit Remarks
Minimum Maximum
b
CF - μm Minus coplanarity
0,4
SX -0,15 0,15 ° Ferrule surface x-angle
SY -0,2 0,2 ° Ferrule surface y-angle

H 1 3,5 μm Fibre height
HA 0 0,3 μm Adjacent fibre height differential
RF 1 - mm Fibre tip spherical radius
2 000 (convex)
RX - mm Ferrule surface x-radius
-10 000 (concave)
RY 5 - mm Ferrule surface y-radius
CDP - 120 nm Core dip
a
- 17,4
GL
NOTE 1 End face parameter requirements apply to performance grade R .
m12
NOTE 2 Refer to Figure 4 for dimensional references.
NOTE 3 End face geometry to be measured in accordance with IEC 61300-3-30.
NOTE 4 The values in Table 8 are specified in the region of interest (ROI) of 2,900 × 0,675 mm (L × H) as defined
in IEC 61300-3-30 for variant number 1012.
NOTE 5 The values in Table 8 apply for polyphenylene sulphide (PPS) ferrules with a Young’s modulus of 15 GPa
to 20 GPa. Ferrule compression force: 7,8 N minimum and 11,8 N maximum.
a
See IEC 61300-3-30 for description and determination of GL. This parameter is only calculated when ≤ 50 % of
the fibres have core dip.
b
The maximum allowable minus coplanarity, CF, shall be reduced to 0,15 µm when ≥ 50 % of the fibres have core
dip.
7.2 Use of selected fibre in multimode reference-grade connectors
Restricted A1-OM2b to A1-OM5b 50 µm fibre shall be used with a core diameter of
50 μm ± 0,5 μm and a numerical aperture of 0,200 ± 0,002 to restrict the variability of
attenuation measurements using reference connectors.

Annex A
(informative)
Attenuation test limit of reference connectors mated to grade B connectors
m
A.1 General
Reference connectors are specified with tight tolerances for the purpose of reducing
measurement uncertainty and are used mainly as a quality assurance screening tool in
production or in the field after installation. Use of these reference connectors is not normative;
however, when the reference connectors described in this document are used, the specified
connectors is normative.
test limit for grade B
m
NOTE This can be used to inspect for failure modes such as fractured fibres, mechanical stresses, microbending
or macrobending (assuring optical functionality).
A.2 Performance grade B test limit against reference connectors
m
The specified attenuation test limit for connector performance grade B against reference
m
connectors, measured in accordance with IEC 61300-3-4 (insertion method B), is given in
Table A.1.
Table A.1 – Performance grade test limits at 850 nm
Reference connector-to- grade B standard
m
connector attenuation test limit
Reference grade
(dB)
R
m2
R
m4
0,45
R
m8
R
m12
A.3 Attenuation grade of reference connectors
The attenuation of Grade R , R , R , and R reference connectors for rectangular PC
m12 m8 m4 m2
ferrules are expected to be lower than 0,15 dB, when measured against another randomly
chosen reference connector according to this document (see Figure A.1).
Limiting the fibre core/cladding eccentricity can be necessary to achieve the required true
position of the fibre core in the ferrule.
Figure A.1 – Calculated attenuation of random mated Grade R reference connectors
m12
Bibliography
IEC 61754-5, Fibre optic interconnecting devices and passive components – Fibre optic
connector interfaces – Part 5: Type MT connector family
IEC 61754-25, Fibre optic interconnecting devices and passive components – Fibre optic
connector interfaces – Part 25: Type RAO connector family
IEC TR 62627-04, Fibre optic interconnecting devices and passive components – Technical
report – Part 04: Example of uncertainty calculation: Measurement of the attenuation of an
optical connector
IEC 63267-2-2, Fibre optic interconnecting devices and passive components – connector
optical interfaces for enhanced macro bend multimode fibres – Part 2-2: Connection parameters
of physically contacting 50 µm core diameter fibres – Non-angled and angled for reference
connection applications
___________
SOMMAIRE
AVANT-PROPOS . 19
1 Domaine d’application . 21
2 Références normatives . 21
3 Termes et définitions. 22
4 Variantes de classe de référence et conventions de numérotation des fibres . 22
5 Classe d’affaiblissement . 23
6 Description . 23
7 Paramètres d’interface de référence . 24
7.1 Géométrie de la fiche de référence après raccordement . 24
7.2 Utilisation de la fibre choisie avec les connecteurs de la classe de référence
pour fibres multimodales . 32
Annexe A (informative) Limite de l’essai d’affaiblissement de connecteurs de
référence accouplés à des connecteurs de classe B . 33
m
A.1 Généralités . 33
A.2 Limite d’essai de la classe de performance B par rapport aux connecteurs
m
de référence. 33
A.3 Classe d’affaiblissement des connecteurs de référence . 33
Bibliographie . 35

Figure 1 – Conventions de numérotation des fibres . 22
Figure 2 – Dimensions de l’interface relatives au décalage latéral et au décalage
angulaire . 25
Figure 3 – Broche d’alignement. 25
Figure 4 – Dimensions de l’interface relatives au décalage longitudinal
(contact physique) . 28
Figure A.1 – Affaiblissement calculé dû à l’accouplement sans choix préalable de
connecteurs de référence de classe R . 34
m12
Tableau 1 – Informations sur les variantes d’interface optique de connecteur de
référence . 22
Tableau 2 – Classe d’affaiblissement de référence en multimodal à 850 nm . 23
Tableau 3 – Dimensions de l’interface optique relatives au décalage latéral et au
décalage angulaire pour la variante d’interface optique R . 26
m2
Tableau 4 – Dimensions de l’interface optique relatives au décalage latéral et au
décalage angulaire pour les variantes d’interface optique R , R et R . 27
m12 m8 m4
Tableau 5 – Dimensions de la géométrie d’extrémité de l’interface optique relatives au
contact physique pour la variante d’interface optique R . 29
m2
Tableau 6 – Dimensions de la géométrie d’extrémité de l’interface optique relatives au
contact physique pour la variante d’interface optique R . 30
m4
Tableau 7 – Dimensions de la géométrie d’extrémité de l’interface optique relatives au
contact physique pour la variante d’interface optique R . 31
m8
Tableau 8 – Dimensions de la géométrie d’extrémité de l’interface optique relatives au

contact physique pour la variante d’interface optique R . 32
m12
Tableau A.1 Limites d’essai de la classe de performance à 850 nm . 33

COMMISSION ÉLECTROTECHNIQUE INTERNATIONALE
____________
Dispositifs d’interconnexion et composants passifs fibroniques -
Interfaces optiques des connecteurs pour fibres
multimodales améliorées en macrocourbures -
Partie 3-81: Paramètres de connexion des fibres d’un diamètre de cœur
de 50 µm en contact physique - Ferrules rectangulaires non inclinées en
polysulfure de phénylène avec une seule rangée de 12, 8, 4 ou 2 fibres,
pour les applications de connecteurs de référence

AVANT-PROPOS
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...