Optical Techniques Take Over Telecommunications

Some 50 years ago it was clear that existing electrical communication systems were leading to a severe bottleneck in bandwidth due to the limited carrier frequencies available. Various optical techniques were examined with little success until the most unlikely one, glass fiber transmission lines, were taken up almost as a last resort. These have turned out to be remarkably successful by increasing transmission distance by a factor x10 and bandwidth by x10(6). The paper reviews progress in passive and active fiber techniques, concluding that fiber technology will produce many further major advances.