City of Light: The Story of Fiber Optics

A VISION OF THE FUTURE 77
reach from your desk to the wall jack for a telephone line. No one knew how
to make fibers carry light over the much greater distances needed for communication
lines.
A second problem was the tremendous success of radio and electronics
technology. Wires and radio links reached around the globe; satellites were
on the horizon. Optical communication through the air had been tried in the
nineteenth century but lost the race to the electrical telegraph and telephone.
Radio transmission was pushing to higher frequencies; semiconductors were
opening new possibilities in electronics. Optics seemed a backwater in comparison.
Moreover, communications engineers knew their task had become far
more complex than carrying voices from one room to the next, as Alexander
Graham Bell had done in 1876. Telephone signals traveled circuitous paths,
following wires from one home to a switching center, which routed them to
another switch, and another, until they finally reached their destination. The
system was as vast and complex as the network of tiny streams that ultimately
combine into the mighty Mississippi River. The switches represented
another crucial level of complexity, because they had to work together to
make connections between any pair of telephones. A whole infrastructure of
electrical, mechanical, and electronic technology supported the telephone system
and seemed destined to dominate in the future.
You had to be a little crazy to challenge that conventional wisdom, and
Alec Harley Reeves had a dash of the requisite madness about him. He was
an idealistic and eccentric British bachelor whose hobby was investigating
the paranormal. Yet he was not just another dotty, aging gentleman. The
cognoscenti of communications knew him as a genuine visionary, an intuitive
engineer who had seen the potential of digital electronics in the 1930s. In
the 1950s, Reeves started looking to light. Initially, fiber optics were not part
of the picture.
An Array of Pipes and Switches
The job of the telephone network is to carry signals from your phone to any
other phone. In recent years, the network has expanded to carry many signals
besides voices, and mobile as well as fixed phones, but the principles remain
the same. The network that does the job is, in essence, an array of pipes and
switches. The pipes carry the signals from point to point; the switches direct
the signals. You need both pipes and switches to have a working phone system.
Either one or both can be bottlenecks that limit how well the system
operates.
When the phone system began, telephone companies ran wires from every
phone to a central ‘‘office’’ where people did the switching needed to complete
calls. Operators sat at switchboards with arrays of holes, one for each phone,
and people signaled them when they wanted to place a call. The operator
responded by connecting an instrument to the hole leading to the caller’s