Overview
IEC 60793-1-45:2024 - "Optical fibres - Part 1-45: Measurement methods and test procedures - Mode field diameter" is the third edition (Edition 3.0, 2024). It defines uniform requirements and standardized measurement methods for determining the mode field diameter (MFD) of single-mode optical fibre. The standard supports consistent inspection and commercial acceptance testing of fibres and cables by specifying test procedures, apparatus, sampling and calculation methods.
This edition is a technical revision of the 2017 version and includes two notable updates:
- Modification of the minimum distance between the fibre end and detector for the direct far-field scan (Annex A).
- Generalization of the minimum dynamic range requirement for all fibre types (Annex A).
Key topics and technical requirements
The standard provides normative requirements and guidance on:
- Reference test methods and four specific measurement techniques:
- Method A - Direct far-field scan
- Method B - Variable aperture in the far field
- Method C - Near-field scan
- Method D - Optical Time Domain Reflectometer (OTDR) based method
- Apparatus specifications including light sources, input/output optics, detectors, positioners, cladding mode strippers and high-order mode filters.
- Sampling and sample preparation (sample length, end-face quality).
- Detailed procedures for measurement, data folding/centroid calculations, integration and conversion relationships between methods.
- Calculation formulas, required integrals and data processing steps to report MFD.
- Result reporting and specification information required for commercial documentation.
- Normative annexes with method-specific requirements and sample data sets.
Keywords: Mode Field Diameter, MFD measurement, single-mode fibre, far-field scan, near-field scan, OTDR, IEC 60793-1-45, optical fibre testing.
Practical applications and who uses this standard
IEC 60793-1-45:2024 is intended for:
- Optical fibre manufacturers - to characterize and certify MFD for product specifications and quality control.
- Test laboratories and inspection services - to perform accredited, repeatable MFD measurements for acceptance testing.
- Cable and component manufacturers - to ensure compatibility of fibres, connectors and splices.
- Network operators and system integrators - for link design, splice-loss estimation and component matching.
- Equipment suppliers - to design MFD-capable measurement instruments and calibration references.
Practical benefits include consistent MFD data for commercial contracts, improved splice/connector performance prediction, and harmonized test reporting across the industry.
Related standards
- Other parts of the IEC 60793 series covering optical fibre definitions and characteristics.
- Complementary optical fibre and cable test standards (e.g., IEC 60794 family) for cable-level testing and installation acceptance.