IEC 60793-1-44:2023

Overview

IEC 60793-1-44:2023 - "Optical fibres - Part 1-44: Measurement methods and test procedures - Cut-off wavelength" specifies standardized procedures for measuring the cut-off wavelength of single‑mode optical fibres. The standard establishes uniform requirements used for inspection and commercial acceptance of uncabled and cabled telecom fibres across category B and C fibre types. The third edition (2023) is a technical revision of the 2011 edition and adds clarifications (loop diameter deployment), Annex D on cut-off curve artifacts, and more figures to aid interpretation.

Keywords: IEC 60793-1-44:2023, cut-off wavelength, optical fibres, single-mode, measurement methods.

Key topics and technical requirements

• Scope and applicability
  • Procedures apply to uncabled and cabled single‑mode telecom fibres for categories B and C.
• Three deployment methods
  • Method A - cable cut-off using an uncabled fibre sample, 22 m (λcc).
  • Method B - cable cut-off using a cabled fibre sample, 22 m (λcc).
  • Method C - fibre cut-off using an uncabled fibre sample, 2 m (λc).
• Reference-scan techniques (required for all methods)
  • Bend-reference technique (mode filtering via controlled bends).
  • Multimode-reference technique using category A1 (OM1–OM5) multimode fibre.
• Apparatus and measurements
  • Requirements and guidance for light sources, modulation, launch optics, detection optics, detectors, cladding‑mode strippers, deployment mandrels and specimen end‑face preparation.
  • Detailed procedures for specimen positioning, output power measurement, calculations, mapping functions, and result reporting.
• Analysis and artifacts
  • Annex D describes cut‑off curve artifacts and a curve‑fitting technique to filter artifacts and compute the cut‑off wavelength reliably.
• Documentation
  • Normative references and cross‑references to the IEC 60793‑1 series (measurement methods and test procedures).

Practical applications and who uses this standard

• Manufacturers of single‑mode optical fibre and cabled products: to verify performance during production and for commercial acceptance testing.
• Qualification and testing laboratories: to perform repeatable, repeatable cut‑off measurements and provide test reports that align with international practice.
• Telecommunications procurement and quality assurance teams: to specify acceptance criteria and interpret supplier test data.
• Research and development groups working on fibre designs requiring validated mode‑field and cut‑off characterization.

Benefits include consistent test methods for vendor comparisons, traceable results for contract compliance, and guidance to mitigate measurement artifacts.

Related standards

• IEC 60793-1-1 (general measurement methods) and other parts of the IEC 60793-1 series for complementary measurement and terminology guidance.