Optics vs. copper — From the perspective of Thunderbolt 3 interconnect technology

"Thunderbolt 3" has adopt both copper and optical interconnect technologies, depends on the cable length used. Single cable can now support 2×20Gb/s of data throughput driven by the 4K video which quickly becomes the mainstream. Future 8K video only pushes the bandwidth requirement even higher. Both copper and optical interconnect technologies are compared on the basis of cost, power, form factor, and scalability. New technologies developed to enable this high data rate for consumer electronics are also discussed, such as robust copper and optical cables, miniature optical engine, and low power integrated circuits for VCSEL and photodetector.