IEC/TR 61292-4 Ed. 4.0 en:2023

Optical amplifiers - Part 4: Maximum permissible optical power for the damage-free and safe use of optical amplifiers, including Raman amplifiers.

IEC TR 61292-4:2023 is available as IEC TR 61292-4:2023 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.

IEC TR 61292-4:2023, which is a Technical Report, applies to all commercially available optical amplifiers (OAs), including optical fibre amplifiers (OFAs) using active fibres as well as Raman amplifiers. Semiconductor optical amplifiers (SOAs) using semiconductor gain media are also included.

This document provides informative guidelines on the threshold of high optical power that can cause high-temperature damage of the fibre. Also discussed is optical safety for manufacturers and users of optical amplifiers by quoting parts of existing standards and agreements on eye and skin safety.

This document identifies the following values for maximum permissible optical power in the optical amplifier for damage-free and safe operation:

• the optical power limit that causes thermal damage to the fibre, such as fibre fuse and fibre-coat burning;
• the maximum permissible exposure (MPE) to which the eyes/skin can be exposed without consequent injury;
• the optical power limit in the fibre that causes MPE on the eyes/skin after free-space propagation from the fibre;
• the absolute allowable optical power level for damage-free and safe operation of the optical amplifier by comparing a) and c).

The objective of this document is to minimize potential confusion and misunderstanding in the industry that can cause unnecessary alarms and hinder the progress and acceptance of advancing optical amplifier technologies in the market. It is important that the reader always refers to the latest international standards and agreements, because the technologies concerned are rapidly evolving.

The present document will be frequently reviewed and updated in a timely manner by incorporating the results of various studies related to OAs and OA-supported optical systems. This fourth edition cancels and replaces the third edition published in 2014. This edition constitutes a technical revision.

This edition includes the following significant technical changes with respect to the previous edition:

• a) The technical information has been updated to reflect revisions of the relevant references.
• b) In particular, the descriptions provided in Clause 5 and Clause 6 have been modified significantly to reflect changes in the cited references. Unnecessary formulas and explanations that overlap with the references have been removed to simplify the document.
• c) New information has been added to Annex A on optical fibre burning when light enters an optical fibre with a bubble train formed by a fibre fuse.