Development of fiber optic liquid crystal sensor for pressure measurement

This paper presents a further development of a novel fiber optic low and high hydrostatic pressure sensing technique utilizing new classes of chiral nematic liquid crystals with a significantly reduced thermal sensitivity. The low-pressure sensor (up to 1 MPa) is based on polarization effects caused by strong rotatory power of chiral nematics and pressure-induced deformations of a twisted nematic cell. The high-pressure sensor (up to 60 MPa) is based on intensity phenomena occurring in novel classes of chiral nematics with induced smectic A/sub d/ phase. The latest results indicate that our method of hydrostatic pressure measurement offers high response to pressure with reduced temperature sensitivity.