Photonic crystal fibers (PCFs) have attracted the interest of many researchers in recent years due to their unusual optical properties. PCFs can be endlessly single mode over a wide wavelength range, and can be tailored to achieve nearly zero and flat dispersion over a wide range of wavelengths. Recently, some attention has been devoted to the possibility of infiltration of the air holes with different materials such as polymer, oil, or liquid crystal (LC). However, PCF structure infiltrated with a LC has unique and uncommon propagation and polarization properties. In this talk, novel designs of high birefringence LC PCF infiltrated with a nematic liquid crystal (NLC-PCF) are presented and analyzed. In addition, due to their different uses in communication systems, the performance of novel designs of high tunable polarization rotator, directional coupler, polarization splitter, and multiplexer-demultiplexer based on the NLC-PCF will be introduced. Moreover, LC Photonic crystal based optical router and image encryption will be presented. The simulation results are obtained using full vectorial finite difference method, and full vectorial finite difference beam propagation method, finite difference time domain method (FDTD) with nonuniform meshing capabilities and perfect matched layer boundary conditions.