HONG KONG — Charles Kuen Kao, a Nobel laureate in physics whose research in the 1960s revolutionized the field of fiber optics and helped lay the technical groundwork for the information age, died on Sunday in Hong Kong. He was 84.

His death was confirmed by the Hong Kong-based Charles K. Kao Foundation for Alzheimer’s Disease, which he and his wife, Gwen Kao, founded in 2010. The foundation declined to specify a cause but said that Dr. Kao learned he had the disease in 2002.

Working in Britain in the late 1960s, Dr. Kao and a colleague played a crucial role in discovering that the fiber optic cables in use at the time were limited by impurities in their glass. They also outlined the cables’ potential capacity for transmitting information — one that was far superior to that of copper wires or radio waves.

“The word ‘visionary’ is overused, but I think in the case of Charles Kao, it’s entirely appropriate because he really did see a world that was connected, by light, using the medium of optical fiber,” said John Dudley, a researcher in fiber optics based in France and a former president of the European Physical Society. “And I think society today owes him a great deal for that work.”