"A teacher told Kapany that light could travel only in a straight line. Kapany set out to prove him wrong."
Fortune Magazine (1999)
Optical fiber, made from glass or plastic, is used to guide light from a source to another location. First used in medicine to examine internal organs, the technology has since been developed for many applications, including telecommunications.
Indian-born Narinder Singh Kapany (b 1927) is the father of fiber optics. While undertaking research at Imperial College in London in 1952, Kapany drew out fine filaments of optical-quality glass and found that when he shone a light in at one end, it emerged unchanged from the other, even if the fiber was twisted. The concept behind optical fibers was first shown by Irish inventor John Tyndall, who used the principle to illuminate water fountains in the 1850s.
Kapany discovered that light was guided by total internal reflection within the glass fiber and that each fiber could carry many different wavelengths of light simultaneously over considerable distances. Adding a glass coating to the fiber increased its effectiveness by increasing the fiber's internal reflectivity. These qualities make optical fiber better than copper wires for many applications.
The concurrent development of laser technology was combined with optical fiber technology in the mid-1960s. While working for Standard Telephones and Cables of Essex, United Kingdom, Charles Kao realized that the attenuation of signal in optical fibers could be reduced by eliminating impurities in the glass. His work paved the way for today's use of optical fibers in telecommunications, where they form the majority of long-distance telephone and computer communication cabling worldwide.
