Zero-birefringence photosensitive polyimides for optical waveguides

Zero-birefringence (delta n < 1 x 10(-6)) photosensitive fluorinated polyimides are synthesized for use in polymer optical waveguides. To obtain zero birefringence, the UV exposure time and copolymer content of photosensitive polyimides are controlled. Zero birefringence combined with photoprocessing of the material has excellent potential for applications in high-performance wavelength division multiplexing components such as polarization-independent arrayed waveguide gratings and Bragg wavelength filters.