Fabrication of test structures for 4×4 InP/InGaAsP integrated optical matrix

A novel optical switching matrix measuring 1×2 mm2 in size is fabricated. The switching matrix is composed of waveguides, four 1×4 multimode interference (MMI) splitters, 32 total internal refraction mirrors and four 4×1 MMI combiners with the extremely compact size of 1×2 mm2. This integrated device are assessed and loss contribution measured from test structure is presented.

High bandwidth optical links over multimode fibre

A Fabry-Perot laser source operating at 1300 nm was modulated at 2.5 Gb/s with a 27-1 pseudo-random bit sequence. Three techniques were examined for increasing the bandwidth of optical links using multimode fiber (MMF). With an offset launch of 14 μm, the eye remained open after the 2 km link of 50 μm core MMF containing seven connectors and three splices. An approximate four-fold bandwidth improvement was obtained using the offset launch with a bandwidth-length product of 7.5 Gb/s.km and a bit error rate below 10-10. The bandwidth enhancement was stable against environmental influences on the fiber link, such as mechanical agitation. Detailed simulations demonstrated that the technique allows enhanced operating bandwidths in over 99% of existing link.