COMPLETELY ADIABATIC S-SHAPED BENT TAPERS IN OPTICAL WAVE-GUIDES

A novel S-shaped bent taper comprised the functions of bent and tapere d structures is proposed to extend the applications of tapers with str aight axes. The optimal combination of taper shape and refractive-inde x distribution in such an ideal structure is obtained by applying the conformal mapping technique to transform a single-mode straight wavegu ide into an equivalent tapered configuration, Furthermore, the beam pr opagation method in conjunction with the conformal mapping technique i s used to analyze the optical propagation characteristics of ideal str uctures, Simulation results predict that a perfect mode-size conversio n and a lateral shift of optical propagation can be achieved adiabatic ally.