Electromagnetic Modeling for Symmetrical 2x2 Fused Fiber-Optic Couplers

• Main Authors: Szu-Wen Yang, 楊思文
• Other Authors: Hung-chun Chang
• Format: Others
• Language: en_US
• Published: 1996
• Online Access: http://ndltd.ncl.edu.tw/handle/03419125090168423267

碩士 === 國立臺灣大學 === 電機工程研究所 === 84 === The propagation characteristics of symmetrical 2x2 fused fiber- optic couplers made of two identical fibers are theoretically investigated using the surface integral equation method (SIEM) in this research. By nonuniformly dividing the boundary contour of the dumbbell-shaped cross-section of the coupler, the accurate coupling characteristics, including the coupling coefficients of x and y polarization states and the form birefringence, have been calculated. For the more strongly fused couplers, an improved model of the coupler's cross- section, which is no longer dumbbell-shaped, has been adopted. A three-dimensional electromagnetic model for the fused tapered couplers has been developed by combining the SIEM and the step- like approximation method for the tapered structure. The simulation results agree well with the measured coupling behaviors of the practical fused couplers fabricated in our group. The characteristics of the couplers with different structure parameters are analysed in detail. Using the 3-D modeling, the fused couplers with various functions can be designed.