Abstract

A wide variety of optical fibre sensors employing different sensing configurations and signal processing techniques have been developed [1]. One sensor which has shown significant potential for practical sensing of parameters such as temperature and strain is the fibre Fabry-Perot sensor. These have been constructed using a variety of techniques including air-glass interfaces [2], semireflective splices [3,4] and in-fibre Bragg gratings (IFBG)[5]. Recently there has been considerable interest in using low coherence techniques to interrogate sensors as these are capable of making absolute measurements which do not suffer from loss of reference when measurements are interrupted. Of particular recent interest is the use of synthesised low- coherence sources using multiple optical wavelengths as these sources can give very short low-coherence fringe patterns in which the central fringe is much more easily identified.

© 1996 Optical Society of America