Characteristics of S-bend optical waveguides based on back-to-back and sinusoidal structures

Bending waveguide is used to connect two separated optical waveguides. But the bend will produce a huge loss. The bending loss can be reduced by designing effective refractive index for the core and cladding, the radiator curvature bend, and S-shaped bend design. In this paper, we will compute radiation loss between two geometrics structure waveguide bend, a back-to-back and sinusoidal on symmetrical slab waveguide. From the simulation result, we can obtain the radiation loss depends on Δn in slab waveguide. Radiation loss will decrease when Δn and length of the waveguide increase. Then we obtain the comparison characteristics of radius curvature and radiation loss of S-bend optical waveguides bend based on back-to-back and sinusoidal.