City of Light: The Story of Fiber Optics

118 CITY OF LIGHT
devices making bulky vacuum tubes obsolete. He could envision optical fibers
as another technological revolution, doing the same thing to millimeter waveguides.
It was the chance of a lifetime. Ambitious young engineers dream not
just of making something work, but of making it work so well that it brings
them fame and fortune, putting them in the league of people like Reeves, or
perhaps even Thomas Edison and Alexander Graham Bell.
The dream is not easy to achieve. Kao could not be sure in 1966 that
glass could ever be as clear as he needed. Other engineers were skeptical.
‘‘We were talking about a system concept which required a light source which
at that time was working intermittently in liquid nitrogen, and an order of
magnitude improvement in fiber that was so far out that people could not
believe it was an attainable goal,’’ Kao told me on the phone. He had to sell
them on the dream. ‘‘I sometimes say I must be a very good salesman.’’ 2 His
words sped from Hong Kong to Boston through 8000 miles of fiber-optic cable
so clear I could catch the faint touch of China beneath his British-English
accent.
A Customer at the Post Office
The January 1966 talk in London opened Kao’s sales campaign. His dream
caught the imagination of a crucial member of the audience, Robert Williamson
White, head of a waveguide development section at the British Post Office
Research Station at Dollis Hill in London, the British counterpart of Bell Labs.
The Post Office had about a hundred people working on the millimeter waveguide,
3 but White was growing skeptical about its prospects and called it ‘‘the
pipe dream.’’ 4
What bothered White was the mundane matter of installation. Millimeter
waveguides had to be buried five to six feet underground and run in straight
lines. That was going to be expensive. The cost might be justifiable to provide
the very high transmission capacity needed for the ‘‘trunk’’ lines between
major cities, especially where they ran through open countryside. However,
the Post Office also wanted to improve the much larger ‘‘junction network’’
linking local telephone switching centers. Like local roads feeding into an
expressway, there are many miles of junction network for each mile of trunk.
Connections typically span only a few miles, but they thread through existing
cities and towns. Millimeter waveguides were as ill-matched to winding along
the tangled streets of London as rigid metal pipes were to looking down a
patient’s throat into his stomach. Post Office engineers wanted a cable they
could snake through utility ducts already buried underground. Thin and flexible,
optical fibers sounded worth investigating.
Technology led the way at Dollis Hill. Managers felt ‘‘if the technology can
deliver it, let’s do it and see how the customer reacts,’’ 5 says Jack Tillman, a
former deputy director for research. That attitude led the British lab to study
telephone access to remote computer systems as far back as 1960. 6 That
interest led to a commercial service called Prestel, which floundered in the