Paul E. Blaszyk

Polarization properties of birefringent fibers with stress rods in the cladding

The polarization properties of fibers with high-expansion aluminum-doped stress rods in the cladding are described. Polarization beat lengths and polarization-holding parameters comparable to those of state-of-the-art high-birefringence fibers are obtained. The diameter of the outer cladding is not sufficient to provide optimum constraint on the stress rods. Increasing the diameter of this region should significantly reduce both the beat length and the polarization-holding h - parameter. No anomalous behavior or thermal hysteresis is observed in the temperature dependence of the fiber birefringence below 600°C. Above 600°C, a permanent hysteresis which reduces the fiber birefringence is observed.

Polarization Retaining Single-Mode Fiber With Improved Coil Performance

High birefringence, polarization retaining single-mode optical waveguides have been developed for applications requiring stable performance when the fiber is coiled. Recent designs employing high-expansion aluminum-doped stress rods have demonstrated polarization holding parameters better than 6.0 x 10-6m-1 with little degradation of h-parameter or attenuation down to 2 cm diameter coil configurations.

Design and Characterization of Optical Waveguides for Gyro Applications

Polarization retaining single-mode fibers are being developed using the stress-rod approach. Design parameter values have been varied to optimize birefringence, polarization holding, and low attenuation rates. Test configurations have been developed to characterize the fibers under simulated deployment bending conditions. The results show that good polarization and attenuation properties can be maintained for long lengths of fibers wound into compact sensor configurations.