Abstract: An integrated planar waveguide system including at least two primary waveguides for light propagation and coupling, and two or more mirror-imaged symmetrization structures in close proximity to the primary waveguides in order to provide micro-process-equalization during etch, growth, annealing and reflow processes. The primary waveguides are designed to carry light signals. The symmetrization waveguide structures are designed so that all the trenches between primary waveguides are identical to the desired degree. At the same time, the symmetrization structures are designed to have minimal detrimental impact on the optical performance of the coupler.

Abstract: A waveguide and resonator are formed on a lower cladding of a thermo optic device, each having a formation height that is substantially equal. Thereafter, the formation height of the waveguide is attenuated. In this manner, the aspect ratio as between the waveguide and resonator in an area where the waveguide and resonator front or face one another decreases (in comparison to the prior art) thereby restoring the synchronicity between the waveguide and the grating and allowing higher bandwidth configurations to be used. The waveguide attenuation is achieved by photomasking and etching the waveguide after the resonator and waveguide are formed. In one embodiment the photomasking and etching is performed after deposition of the upper cladding. In another, it is performed before the deposition. Thermo optic devices, thermo optic packages and fiber optic systems having these waveguides are also taught.