IEC 61280-1-4-2023 PDF

Full title and description

Fibre optic communication subsystem test procedures - Part 1-4: General communication subsystems - Light source encircled flux measurement method. This international standard specifies the characterization and measurement procedure for the encircled flux (EF) of light sources intended for use with multimode optical fibre, including acquisition of near‑field greyscale images and reduction to radial encircled‑flux functions for evaluation and specification.

Abstract

IEC 61280-1-4:2023 (Edition 3.0) defines a standardized method to measure and report encircled flux from multimode light sources. The document describes required apparatus, geometric calibration, image acquisition (including dark‑image correction), optical‑centre determination, computation of encircled flux and related baseline/integration limits. The 2023 edition is a technical revision of the 2009 edition that improves calibration traceability, refines the fibre shaker requirements, adds guidance for pulsed light sources and removes a micro‑positioner based calibration method. It is intended to provide repeatable, comparable EF characterisation for test laboratories, manufacturers and equipment developers.

General information

• Status: Published — International Standard (current edition).
• Publication date: 19 January 2023.
• Publisher: International Electrotechnical Commission (IEC).
• ICS / categories: 33.180.01 (Fibre optic systems in general).
• Edition / version: Edition 3.0 (2023).
• Number of pages: 59 pages.

Scope

This part of IEC 61280 establishes the characterization and measurement procedure for the encircled flux measurement method applied to light sources for multimode fibre systems. It specifies the collection of two‑dimensional near‑field greyscale data and the reduction to one‑dimensional radial encircled‑flux functions (sampled parametric functions of radius from the optical centre). The standard does not aim to determine fibre core diameter; rather it defines repeatable conditions and processing for EF characterization of launch sources and measurement devices.

Key topics and requirements

• Definition and purpose of encircled flux (EF) for multimode light‑source characterization.
• Required apparatus: image digitizer, detector, magnifying optics, attenuator and recommended input port arrangements.
• Geometric calibration procedures and calibration traceability requirements.
• Image acquisition workflow: raw and dark images, corrected image computation and optical‑centre (centroid) determination.
• Data reduction: computation of radial data functions, integration limits, baseline determination and sampling of EF curves.
• Specific test fixturing and dynamic conditions: description and requirements for a fibre shaker to randomize modal distribution.
• Inclusion of pulsed light‑source measurement guidance and removal of a micro‑positioner calibration method from earlier editions.
• Reporting and specification information to ensure comparability between instruments and laboratories.

Typical use and users

Used by optical test laboratories, multimode transceiver and source manufacturers, component and test‑equipment vendors, R&D groups and standards conformity assessors to characterise and specify the modal launch condition provided by a light source or test launch. The standard supports reproducible testing for product development, product specifications, qualification and field test validation where controlled multimode launch conditions are important.

Related standards

IEC 61280 is a multipart series of fibre‑optic subsystem test procedures. Relevant related parts and documents include other general‑subsystem parts (for example IEC 61280‑1‑3 for spectral/central wavelength measurements) and installed‑plant measurement parts (for example IEC 61280‑4‑1 and its corrigenda) as well as newer parts covering digital‑system measurements (parts in the IEC 61280‑2 family). Users commonly apply IEC 61280‑1‑4 together with adjacent parts of the 61280 series for comprehensive subsystem testing.

Keywords

encircled flux, multimode fibre, near‑field measurement, image digitizer, geometric calibration, fibre shaker, pulsed light source, test procedure, IEC 61280, launch conditions, calibration traceability

FAQ

Q: What is this standard?

A: IEC 61280‑1‑4:2023 is the International Standard that specifies the measurement method and characterization procedures for the encircled flux of light sources used with multimode optical fibre.

Q: What does it cover?

A: It covers apparatus requirements, geometric calibration, image acquisition and processing, computation of encircled‑flux radial functions, test sample handling and reporting formats to ensure repeatable EF characterisation for multimode sources (including guidance for pulsed sources).

Q: Who typically uses it?

A: Test laboratories, fibre‑optic component and transceiver manufacturers, test‑equipment vendors, R&D teams and quality/conformity assessors who need standardized, repeatable characterization of multimode launch conditions.

Q: Is it current or superseded?

A: This is the current (third) edition, published 19 January 2023; it cancels and replaces the 2009 edition and is the operative version for encircled‑flux measurement procedures.

Q: Is it part of a series?

A: Yes — IEC 61280 is a multipart series of fibre‑optic communication subsystem test procedures. Part 1‑4 focuses on EF measurements; other parts in the series cover spectral measurements, digital‑system tests and installed‑plant attenuation/ORL measurements, among others.

Q: What are the key keywords?

A: Encircled flux, multimode, near‑field, launch conditions, calibration, fibre shaker, image acquisition, EF radial functions, IEC 61280.