This part of IEC 61292, 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.<\/p>\n
This technical report provides a simple informative guideline on the threshold of high optical power that causes high-temperature damage of fibre. Also discussed is optical safety for manufacturers and users of optical amplifiers by reiterating substantial parts of existing standards and agreements on eye and skin safety.<\/p>\n
To identify the maximum permissible optical power in the optical amplifier from damage-free and safety viewpoints, this technical report identifies the following values:<\/p>\n
the optical power limit that causes thermal damage to the fibre, such as fibre fuse and fibre-coat burning;<\/p>\n<\/li>\n
the maximum permissible exposure (MPE) to which the eyes\/skin can be exposed without consequential injury;<\/p>\n<\/li>\n
the optical power limit in the fibre that causes MPE on the eyes\/skin after free-space propagation from the fibre;<\/p>\n<\/li>\n
the absolute allowable damage-free and safe level of optical power of the optical amplifier by comparing (a) and (c).<\/p>\n<\/li>\n<\/ul>\n
The objective of this technical report is to minimize potential confusion and misunderstanding in the industry that might cause unnecessary alarm and hinder the progress and acceptance of advancing optical amplifier technologies and markets.<\/p>\n
It is important to point out that the reader should always refer to the latest international standards and agreements because the technologies concerned are rapidly evolving.<\/p>\n
The present technical report will be frequently reviewed and will be updated by incorporating the results of various studies related to OAs and OA-supported optical systems in a timely manner.<\/p>\n
| PDF Pages<\/th>\n | PDF Title<\/th>\n<\/tr>\n | ||||||
|---|---|---|---|---|---|---|---|
| 4<\/td>\n | CONTENTS <\/td>\n<\/tr>\n | ||||||
| 6<\/td>\n | FOREWORD <\/td>\n<\/tr>\n | ||||||
| 8<\/td>\n | INTRODUCTION <\/td>\n<\/tr>\n | ||||||
| 9<\/td>\n | 1 Scope and object 2 Normative references <\/td>\n<\/tr>\n | ||||||
| 10<\/td>\n | 3 Abbreviated terms 4 Maximum transmissible optical power to keep fibres damage-free 4.1 General <\/td>\n<\/tr>\n | ||||||
| 11<\/td>\n | 4.2 Fibre fuse and its propagation Figures Figure 1 \u2013 Experimental set-up for fibre fuse propagation Tables Table 1 \u2013 Threshold power of fibre fuse propagation for various fibres <\/td>\n<\/tr>\n | ||||||
| 12<\/td>\n | 4.3 Loss-induced heating at connectors or splices Table 2 \u2013 Measurement conditions <\/td>\n<\/tr>\n | ||||||
| 13<\/td>\n | 4.4 Connector end-face damage induced by dust\/contamination Figure 2 \u2013 Connection loss versus temperature increase Figure 3 \u2013 Test set-up <\/td>\n<\/tr>\n | ||||||
| 14<\/td>\n | Figure 4 \u2013 Surface condition contaminated with metal filings, before the test <\/td>\n<\/tr>\n | ||||||
| 15<\/td>\n | 4.5 Fibre-coat burn\/melt induced by tight fibre bending Figure 5 \u2013 Variation of the power attenuation during the test at several power input values for plugs contaminated with metal filings Figure 6 \u2013 Polishing surface condition contaminated with metal filing, after the test <\/td>\n<\/tr>\n | ||||||
| 16<\/td>\n | 4.6 Summary of the fibre damage Figure 7 \u2013 Thermo-viewer image of tightly bent SMF with optical powerof 3 W at 1\u00a0480\u00a0nm Figure 8 \u2013 Temperature of the coating surface of SMFs against bending with optical power of 3 W at 1 480 nm <\/td>\n<\/tr>\n | ||||||
| 17<\/td>\n | 5 Maximum transmissible optical power to keep eyes and skin safe 5.1 Maximum transmissible exposure (MPE) on the surface of eye and skin 5.2 Maximum permissible optical power in the fibre for the safety of eye and skin 5.2.1 General <\/td>\n<\/tr>\n | ||||||
| 18<\/td>\n | Table 3 \u2013 Examples of power limits for optical fibre communication systems having automatic power reduction to reduce emissions to a lower hazard level <\/td>\n<\/tr>\n | ||||||
| 19<\/td>\n | 5.2.2 Need for APR 5.2.3 Wavelengths 5.2.4 Locations 5.2.5 Nominal ocular hazard distance (NOHD) 5.2.6 Power reduction times Table 4 \u2013 Location types within an optical fibre communication system and their typical installations <\/td>\n<\/tr>\n | ||||||
| 20<\/td>\n | 5.2.7 Medical aspects of the safety of eyes and skin in existing standards Figure 9 \u2013 Maximum permissible power in the fibre against APR power reduction time <\/td>\n<\/tr>\n | ||||||
| 21<\/td>\n | 6 Maximum optical power permissible for optical amplifiers from the viewpoint of fibre damage as well as eye and skin safety 7 Conclusion <\/td>\n<\/tr>\n | ||||||
| 22<\/td>\n | Annex A (informative) General information for optical fibre fuse A.1 Introductory remark A.2 Generating mechanism Figure A.1 \u2013 Front part of the fibre fuse damage generated in the optical fibre <\/td>\n<\/tr>\n | ||||||
| 24<\/td>\n | Figure A.2 \u2013 SiO absorption model <\/td>\n<\/tr>\n | ||||||
| 25<\/td>\n | A.3 Void formation mechanism Figure A.3 \u2013 Calculated fibre fuse propagation behaviour simulated with the SiO absorption model <\/td>\n<\/tr>\n | ||||||
| 26<\/td>\n | A.4 Propagation characteristic of a fibre fuse Figure A.4 \u2013 Series of optical micrographs showing damage generated by 9,0 W 1\u00a0480\u00a0nm laser light suggesting a mechanism of periodic void formation <\/td>\n<\/tr>\n | ||||||
| 27<\/td>\n | Figure A.5 \u2013 Images of fibre fuse ignition taken with an ultra-high speed camera and an optical micrograph of the damaged fibre Figure A.6\u2013 Power density dependence of the fibre-fuse propagation velocity <\/td>\n<\/tr>\n | ||||||
| 28<\/td>\n | A.5 Prevention and termination A.5.1 General A.5.2 Prevention methods A.5.3 Termination methods A.5.3.1 General A.5.3.2 Passive termination methods Figure A.7 \u2013 Optical micrographs showing front part of the fibre fuse damage generated in SMF-28 fibres with various laser intensities (1\u00a0480\u00a0nm) <\/td>\n<\/tr>\n | ||||||
| 29<\/td>\n | Figure A.8 \u2013 Principle of the optical fibre fuse passive termination method and photograph of the fibre fuse terminator which adopted TEC structure <\/td>\n<\/tr>\n | ||||||
| 30<\/td>\n | A.5.3.3 Active termination methods Figure A.9 \u2013 Photograph of hole-assistant fibre and fibre fuse termination usinga hole-assistant fibre <\/td>\n<\/tr>\n | ||||||
| 31<\/td>\n | A.6 Conclusion Figure A.10 \u2013 Example of fibre fuse active termination scheme Figure A.11\u2013 Transformation of electric signal by optical fibre fuse <\/td>\n<\/tr>\n | ||||||
| 32<\/td>\n | Bibliography <\/td>\n<\/tr>\n<\/table>\n","protected":false},"excerpt":{"rendered":" Optical amplifiers – Maximum permissible optical power for the damage-free and safe use of optical amplifiers, including Raman amplifiers<\/b><\/p>\n |