Propagation characteristics of photonic bandgap fiber collimator with C-lens

A photonic bandgap fiber collimator with C-lens was proposed. The photonic crystal fiber end face does not have reflection, so the transform matrix will change. From the general model of Gaussian-beam imaging, using the theory of matrix optics, the matrix optics was calculated in meridian plane and sagittal plane respectively. Combined with practical applications in photonic bandgap fiber and C-lens related parameters, the influence of the distance between fiber tail and C-lens and the influence of the parameter of the C-lens on working distance and beam waist diameter of collimator were both stimulated and analyzed. The results of the analysis in new model show that the influence of the C-lens tile for meridian plane and sagittal plane was similar, and the Gaussian-beam ellipse was smaller compared with ordinary fiber. The result may direct the design of photonic bandgap fiber collimator and the design of optical device with photonic bandgap fiber collimator.