City of Light: The Story of Fiber Optics

14
Three Generations in Five Years
(1975–1983)
Optical communications, for all its glamour, has already
passed most of the hard tests of practical application. We
know how to draw fibers of the unprecedented degree of
transparency required. We know how to combine those
fibers into cable. We know how to splice the cable. We
have designed and built devices to generate and modulate
optical signals. And we have designed and built repeaters
to regenerate these signals. In short, we have designed
and built a completely integrated optical transmission system.
—John D. deButts, chairman, AT&T, October 17, 1975 1
It is now clear that optical fiber systems will win in the
competition for performance and economy. ...Thefuture
will always be constrained by the physical properties of
materials and by the technological skills developed to overcome
or make use of them. A step-wise move toward wavelengths
of about 1.2 micrometers can be foreseen, limited
largely by the development of efficient and reliable enough
optical sending and receiving elements. The splicing problem
may remain a significant barrier to the wide use of
monomode fiber systems, but other barriers may be set by
the terminal costs and overall network reliability costs as-
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