| Popis: |
Why not silica? Over the past three decades, optical fibres based on high-purity silica, have established themselves as perhaps the ultimate communications material. These global cobwebs of glass have revolutionized telecommunications, reaching virtually every populated region on earth and providing enormous bandwidth, the full extent of which has yet to be exploited. Passive waveguides are today being spliced together with lengths of fibre doped with the rare-earth ion erbium, providing optical fibre amplifiers which can boost a fading signal by three orders of magnitude. This combination of active and passive waveguides, has made possible all optical networks, with no electrical/optical interfaces except at the signal source and receiver, and paved the way for global optical fibre telecommunications. |
