TAPERED WAVEGUIDE FOR OPTICAL DISPERSION COMPENSATION

摘要

An optical device for creating chromatic dispersion which comprises an input receiving an optic communications signal, a first waveguide, a second waveguide and an output for outputting the optic communications signal with modified chromatic dispersio n characteristics. The first waveguide has a first index of refraction and a lateral coupling surface and is able to guide a mode of light. It has a substantially uniform thickness. The second waveguide has a second index of refraction significantly different fr om the first index of refraction and a corresponding lateral coupling surface coupled to the lateral surface of the first waveguide. It also has a variable thickness selected to allow a predetermined wavelength to couple massively from the first to the second waveguide at a predetermined distance along the coupling surface in the direction of propagation of the mode of light, the thickness varying gradually in the direction of propagati on of light so as to allow neighboring wavelength components of an optical signal to undergo chromatic dispersion by coupling from the first waveguide to the second waveguide at different positions.