Pressure sensitivity of side-hole optical fiber sensors

The dependency of the pressure-induced birefringence of a side-hole fiber on its geometry has been numerically investigated using the finite element method. We demonstrate that the pressure sensitivity of such a fiber shows a linear dependence on /spl phi//sup 2/, where /spl phi/ is the angle between the side hole center and core center axis and the core center to side-hole tangent. Experimental data obtained with two different side-hole fiber sensors are shown to agree extremely well (to within 10%) with theoretical predictions.