Polarization & Phase Control

Fiber Polarization Controller Piezoelectric – 0.5dB, 100kHz

The Piezoelectric Polarization Controller (PIPC) uses up to four piezoelectric fiber-squeezing elements spaced 45° apart to induce controlled birefringence and phase retardation in an optical fiber. Each actuator applies variable pressure to the fiber, creating stress-induced birefringence via the photoelastic effect, where the refractive index becomes polarization-dependent. This controlled anisotropy produces a differential phase shift between orthogonal polarization modes, enabling precise polarization rotation and full coverage of the Poincaré sphere. The device is built from a single continuous strand of polyimide-coated fiber, ensuring minimal insertion loss, high reliability, and broadband operation, although the birefringence magnitude has some wavelength sensitivity.