City of Light tells the story of fiber optics, tracing its transformation from 19th-century parlor trick into the foundation of our global communications network. Written for a broad audience by a journalist who has covered the field for twenty years, the book is a lively account of both the people and the ideas behind this revolutionary technology.
The basic concept underlying fiber optics was first explored in the 1840s when researchers used jets of water to guide light in laboratory demonstrations. The idea caught the public eye decades later when it was used to create stunning illuminated fountains at many of the great Victorian exhibitions. The modern version of fiber optics--using flexible glass fibers to transmit light--was discovered independently five times through the first half of the century, and one of its first key applications was the endoscope, which for the first time allowed physicians to look inside the body without surgery. Endoscopes became practical in 1956 when a college undergraduate discovered how to make solid glass fibers with a glass cladding.
With the invention of the laser, researchers grew interested in optical communications. While Bell Labs and others tried to send laser beams through the atmosphere or hollow light pipes, a small group at Standard Telecommunication Laboratories looked at guiding light by transparent fibers. Led by the recipient of the 2009 Nobel Prize in Physics, Charles K. Kao, they proposed the idea of fiber-optic communications and demonstrated that contrary to what many researchers thought glass could be made clear enough to transmit light over great distances. Following these ideas, Corning Glass Works developed the first low-loss glass fibers in 1970.
From this point fiber-optic communications developed rapidly. The first experimental phone links were tested on live telephone traffic in 1977 and within half a dozen years long-distance companies were laying fiber cables for their national backbone systems. In 1988, the first transatlantic fiber-optic cable connected Europe with North America, and now fiber optics are the key element in global communications.
The story continues today as fiber optics spread through the communication grid that connects homes and offices, creating huge information pipelines and replacing copper wires. The book concludes with a look at some of the exciting potential developments of this technology.
The first underwater telegraph cable was laid between England and the Continent in 1850, with the cable from America to Europe following in 1858. But for the next century, improvements in transcontinental communication came slowly. By the 1940s, Americans could talk to Europeans via a static-plagued radiophone. By the early 1980s, satellite transmissions had improved conversation clarity significantly, but callers were still annoyed by delay and feedback. Those who have made a transcontinental call recently, however, know that the wonders of fiber optics have made it possible to hear a pin drop on the Champs-Elysees. In this deft history, Hecht, a writer for the British weekly New Scientist, shows how the illuminated fountains that thrilled crowds at the great 19th-century exhibitions convinced scientists that light can be guided along narrow tubes. In our century, scientists used these tubes of light first to look inside the human body and then, as the physics of wave transmission were better understood, to transmit audio and optical information. Hecht explains which technological advances have made fiber optics the backbone of our telephone system in the last 10-15 years and how everyday applications should increase exponentially once fibers are connected directly to our homes. Already optical fibers are used in many surprising ways: guiding laser light in life-saving surgery; embedded in concrete to monitor stress in bridges; wound into gyroscopes to improve airline safety. Hecht's latter chapters are bogged down slightly with details that will mainly interest readers working in related areas, but general science buffs should enjoy his account of the development of the technology that will change our lives in many unexpected ways in the next quarter century.