IEC 63267-2-1:2024 - Fibre optic interconnecting devices and passive components - Connector optical interfaces for enhanced macro bend multimode fibres - Part 2-1: Connection parameters of physically contacting 50 µm core diameter fibres

Standard No.: IEC 63267-2-1:2024
Release Date: 2024
Published By: International Electrotechnical Commission (IEC) IX / IEC
Latest: IEC 63267-2-1:2024

Introduction

Standard Overview and Technical Background

IEC 63267-2-1:2024 is the latest standard for fiber optic interconnection devices and passive components published by the International Electrotechnical Commission, specifically targeting the connector optical interface of enhanced macrobend multimode fiber. The first part of this standard was officially released in March 2024, marking a new stage in the development of multimode fiber connection technology.

With the continuous growth of bandwidth demand in data centers and high-speed networks, 50/125μm graded-index multimode fiber has been widely used in short-distance communications due to its excellent transmission performance and economy. However, traditional multimode fiber is susceptible to macrobend loss during installation and use, limiting its application in space-constrained environments. Enhanced macrobend multimode fiber significantly improves the bend resistance by optimizing the fiber design, but it also places higher requirements on the connector interface.

Core technical requirements and performance levels

This standard defines the performance levels of random pairing of physically contacted (PC) polished optical fibers based on parameters such as fiber core diameter offset, numerical aperture mismatch and core diameter variation at an operating wavelength of 850nm, using encircled flux (EF) launch conditions in accordance with IEC 61300-1.

Attenuation Performance Level

Performance Level	Average Attenuation (dB)	97% Probability Attenuation (dB)	Application Scenario
Bm Level	≤0.30	≤0.60	High-Performance Data Center
Cm Level	≤0.50	≤1.00	General Enterprise Network
Am Level	Reserved
Grade 1	≥45	Angled Physical Contact (APC) Fiber
Grade 2	≥20	Non-beveled physical contact (PC) optical fiber

Key technical parameters and test methods

Fiber characteristic requirements

The standard applies to IEC 60793-2-10 category A1-OMxb (x = 2, 3, 4, or 5) multimode optical fiber. The core parameter requirements are as follows:

Parameter	Minimum value	Maximum value	Unit
Fiber core diameter	47.5	52.5	μm
Numerical aperture	0.185	0.215	-
Effective group refractive index	1.4835		-

Test method specifications

The standard clearly specifies the test methods for various performances:

Attenuation test: Single-fiber connectors use IEC 61300-3-34, multi-fiber connectors use IEC 61300-3-45
Return loss test: Use the method specified in IEC 61300-3-6
End face inspection: Visual inspection in accordance with IEC 61300-3-35

Connection Parameter Statistical Model and Analysis

The standard uses advanced statistical models to predict performance during random mating. By establishing probability distribution models for lateral offset, numerical aperture mismatch, and core diameter variation, it can accurately predict the parameter limits within which 97% of connected pairs meet performance requirements.

Lateral Offset Limits

Based on the Rayleigh probability distribution model, the standard defines the maximum allowable lateral offset for different performance levels:

Bm Class: Maximum allowable offset is approximately 3μm
Cm Class: Maximum allowable offset is approximately 6μm

Response Surface Analysis

Appendix A of the standard provides a detailed response surface analysis. Using cubic polynomial fitting, it establishes a quantitative relationship between lateral offset, core diameter, and numerical aperture, providing a theoretical basis for connector design and manufacturing.

End-face quality requirements and inspection standards

For PC polished end-faces with return loss level 2 (RL ≥ 20 dB), the standard stipulates strict visual inspection requirements:

Core area (Zone A: 65μm diameter)

Defects: Diameter <2μm, no limit; 2-5μm, maximum 4; >5μm not allowed
Scratches: Width <3μm, no limit; 3-4μm, maximum 4; >4μm not allowed

Cladding area (Zone B: 65-110μm)

Defects: Diameter ≤25μm, no limit; >25μm not allowed
Scratches: No limit

Implementation Recommendations and Best Practices

Connector Selection and Installation

When selecting and installing fiber optic connectors, the following factors should be considered:

Select the appropriate performance grade (Bm or Cm) based on the application scenario
Ensure that the connector end face polish quality meets the standard requirements
Use correct cleaning and maintenance procedures
Perform performance testing and monitoring regularly

Testing and Verification

A comprehensive test and verification system should be established during implementation:

Establish benchmark test conditions to ensure that EF emission meets the requirements
Use statistical methods to evaluate the performance consistency of batch products
Establish a standard operating procedure for end face inspection
Regularly calibrate test equipment to ensure measurement accuracy

Quality Control

Manufacturers should establish a strict quality control system:

Control the tolerance range of key parameters
Implement statistical process control (SPC)
Establish traceable quality records
Perform regular third-party verification testing

Technology Evolution and Future Outlook

The release of the IEC 63267-2-1 standard marks a significant advancement in multimode fiber optic connectivity technology. With the development of 400G and higher speed networks, connector performance requirements will be further enhanced. Future technological development may focus on the following directions:

Higher performance levels: Developing more stringent performance standards such as Am-level
Multi-wavelength support: Expanding to other operating wavelengths such as 950nm
Intelligent monitoring: Integrating intelligent sensing functions to monitor connection status in real time
New material applications: Developing new materials to improve connector durability and performance

This standard provides a solid technical foundation for the application of enhanced macrobend multimode optical fiber, which will have a profound impact on application areas such as data centers, enterprise networks, and 5G fronthaul.

IEC 63267-2-1:2024 Referenced Document

IEC 61300-3-6 Fibre optic interconnecting devices and passive components - Basic test and measurement procedures - Part 3-6: Examinations and measurements - Return loss
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

IEC 63267-2-1:2024 history

2024 IEC 63267-2-1:2024 Fibre optic interconnecting devices and passive components - Connector optical interfaces for enhanced macro bend multimode fibres - Part 2-1: Connection parameters of physically contacting 50 µm core diameter fibres - Non-angled

Fibre optic interconnecting devices and passive components - Connector optical interfaces for enhanced macro bend multimode fibres - Part 2-1: Connection parameters of physically contacting 50 µm core diameter fibres - Non-angled

IEC 63267-2-1:2024Fibre optic interconnecting devices and passive components - Connector optical interfaces for enhanced macro bend multimode fibres - Part 2-1: Connection parameters of physically contacting 50 µm core diameter fibres - Non-angled