Possibilities of application of the side-hole circular core fibre in monitoring of high pressures

The common side-hole (SPI) fibres have high pressure sensitivity K/sub p/. Yet, their temperature sensitivity K/sub T/ is also relatively high. In this article the class of certain structure SH fibres of various core ellipticity was analysed. It was theoretically and experimentally proved that fibres of low core ellipticity have very advantageous K/sub p//K/sub T/ ratio, what permits the construction of pressure sensors which do not require temperature compensation. However, this type of fibres can only be used for the high pressure (above 3 MPa) sensors construction because for lower pressures the beat length is too long.