Abstract

Low-loss waveguide bends are necessary for many proposed integrated optical circuits to improve the packing density, and for certain devices, e.g., directional couplers. Previous bend loss measurements have been reported for Ti: LiNbO₃ at λ = 0.633 μm and 1.06 μm, with losses as low as 0.3 ± 0.3 dB for an S-shaped transition between straights separated by 3 mm longitudinally with an lateral offset of 0.10 mm.¹ For comparable transition regions bend losses of 2-3 dB were measured using two constant curvature segments,² 4 dB using a straight-segment transition,³ and 1.8 dB using three straight segments with coherent coupling.⁴

© 1982 Optical Society of America