To meet the ever increasing bandwidth demands, we need higher data rate, higher channel density and longer interconnect link length in telecom and datacom systems, while at the same time, reducing the power/bit required to transmit and receive signals. For conventional copper electronic interconnect, there are some fundamental obstacles (such as loss, crosstalk, reflection and parasitics) that prevent it from meeting the increasing bandwidth demands.
In the near future, the cost of conventional copper electronic interconnect will exceed the cost of optical interconnect, and optical interconnect will be the preferred solution for short-range interconnect (rack-to-rack, backplane, inter-board, and even inter-chip). Optical PCB technology has been researched for many years, and some groups have already built optical backplane prototypes. Optical backplanes will very likely be applied in high speed systems in the future 5~10 years.
