The flexible polymer optical fiber is prepared with polydimethylsiloxane (PDMS). Femtosecond laser direct writing and slit beam shaping are used to form periodic grating structures in the fiber. This is achieved by creating a periodic variation in the refractive index of the fiber core, which generates a. Key Laboratory of Specialty Fiber Optics and Optical Access Networks, Joint International Research Laboratory of Specialty Fiber Optics and Advanced Communication, Shanghai University, Shanghai 200444, China DTU Electro, Department of Electrical and Photonics Engineering, Technical University of. ABSTRACT: Grating devices in polymer optical fiber (POFs) have attracted interest due to varies potential applications in recent years. This chapter presents the state of the art of the POFBG research, including its fabrication and properties and some typical applications. Two. This article reviews recent research progress on the annealing effects on polymer optical fibers (POFs), which are of great importance for inscription, stability and sensing applications of fiber Bragg gratings (FBGs) in POFs due to their unique properties related to polymer molecular chains.