FIBER-EMBEDDED MANDREL-STIFFENED PLANAR ACOUSTIC SENSOR

A plastic mandrel-based, embedded planar fiber-optic acoustic sensor h as been developed by wrapping a single mode fiber around solid plastic mandrels which are embedded in an elastomeric encapsulant forming a p lanar device. The acoustic sensitivity of the sensor was found to be h igh and frequency independent. The high sensitivity is a result of the effective utilization of the low bulk modulus encapsulant (elastomer) , while the frequency-independent sensitivity is a result of the low a cceleration sensitivity of the sensor due to the out-of-plane fiber co il geometry and the presence of the mandrels. A comparison is made bet ween this sensor and other large area fiber-optic sensor designs. (C) 1995 Acoustical Society of America.