Fibre optic sensor technology: An engineering reality or a scientific opportunity?

Optical fibre sensors have been established now for approaching half a century during which time they have stimulated a great deal of research and some useful practical engineering outcomes. Over the same period we have seen in parallel considerable changes in the photonic tool box of technologies and concepts. The aims of this paper are to take a critical look at the engineering development which we have seen, to assess their contribution and potential for the future, and to speculate on the possibilities which the emerging photonics took box enable for future research and applications. We shall see that whilst the current engineering systems are based upon well established optical principles, both the scientific and technical prospects currently emerging offer significant interest for future research, development and application.