Optical Fiber with High Acceleration Sensitivity and Low Pressure Sensitivity for Use in Spatially Averaging Fiber Optic Accelerometer Sensors.

摘要

An optical fiber which includes a light transmitting center portion, a protecting layer and a stress preventing layer. The protecting layer concentrically surrounds the center portion, and reduces the effect of environmental factors on the center portion. The stress preventing layer concentrically surrounds the center portion and is positioned between the protecting layer and the center portion. The stress preventing layer has a Young's Modulus substantially lower than the Young's Modulus of the protecting layer, for preventing stress from being transferred from the protecting layer to the center portion. The optical fiber can be used in a sensor, wherein the sensor includes an encapsulant and the fiber is embedded in the encapsulant. The embedded fiber is arranged in a pancaked spiral configuration in the encapsulant. Alternatively, the embedded fiber can be arranged to form a plurality of sequential loops. The plurality of sequential loops are then arranged in the same plane as a spiral, where each of the plurality of sequential loops are perpendicular to the plane. A decoupler is also provided for attaching the sensor to a structure, to reduce stretching motion affecting the sensor. (MM).