An optical coupling structure is provided, an exemplary structure has a single-mode polymer waveguide terminated with a lens-shaped coupling structure on each end between an edge emitting laser chip and a single mode fiber. The edge emitting laser is assembled on the lower cladding layer of the waveguide front end with a gap filled with index matching structure, with multiple layers of different index materials for better matching efficiency. Another exemplary structure is a multiple channel polymer waveguide, developed for transmitting optical signals from edge emitting laser arrays to fiber arrays as well as to receive optical signals from fiber array to photodiode arrays. The multiple channel polymer waveguides are assembled with multiple channel connector to link to fiber cable. Multiple channel polymer waveguide cores are made to form angles with waveguide axial direction to compensate for the pitch difference between edge emitting laser channels and the single mode fibers in the fiber cable.