4. Research areas and long-term trends

A number of technological challenges need to be overcome to lower costs and increase the viability of optical interconnections. Higher transmission rates require integrated and/or wavelength-multiplexed transmitters and receivers. Increased link parallelism leads to the development of VCSEL arrays and smart pixels (combining transmitter and receiver on the same chip), and the use of fiber bundles or free-space interconnects. The need for integrated communication modules calls for the new alignment, assembly, encapsulation and heterogeneous integration techniques developed below.

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