Sir Charles Kuen Kao

Modest electrical engineer whose work on fibre optics changed the world

Sir Charles Kuen Kao GBM KBE FRS FRENG, electrical engineer and physicist. Born: 4 November 1933 in Shanghai, China. Died: 23 September 2018 in Sha Tin, Hong Kong, aged 84

Charles Kuen Kao, a Nobel laureate in physics whose research in the 1960s revolutionised the field of fibre optics and helped lay the technical groundwork for the information age, has died.

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 Kao learned he had the disease in 2002.

Working in Britain in the late 1960s, Kao and a colleague played a crucial role in discovering that the fibre optic cables in use at the time were limited by impurities in their glass. They also outlined the cables’ potential capacity for storing 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 fibre,” said John Dudley, a researcher in fibre optics based in France. “And I think society today owes him a great deal for that work.”

In the early 1960s, light pulses carrying telephone and television signals could travel only about 20 metres, or about 65 feet, through glass fibres before nearly all the light dissipated. But by 1970, four years after Kao and British engineer George Alfred Hockham published a landmark study on the subject, a group of researchers had produced an ultrapure optical fibre more than a halfmile long. Fibre optic cables, which look like fishing wire, later enabled the proliferation of broadband communications, biomedical informatics and countless other digital applications. When Kao shared the Nobel Prize in physics in 2009, the Royal Swedish Academy of Sciences estimated that the optical cables in use worldwide, if unravelled, would equal a fibre more than 600 million miles long.

“It’s one of these things where, when you study technology, you start working on one thing, and the impact of it just fans out into all sorts of areas,” Dudley said.

He added that it might have taken decades for Kao to receive the Nobel Prize because the importance of his work was not apparent to the general public until the 2000s.

Carrie Lam, chief executive of Hong Kong, said on Sunday that Kao’s work on fibre optics had made a “tremendous contribution to Hong Kong, the world and mankind”. She added that he had also played a prominent role in shaping local higher education and scientific research.

“An eminent figure, Professor Kao is the pride of Hong Kong people,” Lam said.

Charles Kuen Kao was born in Shanghai in 1933 to a wealthy family, according to an autobiographical sketch published by the Nobel Foundation.

His father, Kao Chun Hsin, was a judge, and his grandfather, Kao Hsieh, had been a Confucian scholar active in a movement to bring down the Qing dynasty during the Chinese Revolution of 1911.

Kao described his early life in Shanghai as “very pampered and protected”. His family moved to Hong Kong when he was 14, on the brink of China’s Communist Revolution of 1949, and at 19 he sailed to England to study electrical engineering at Woolwich Polytechnic, now known as the University of Greenwich.

Kao would later admit that he had not been the most diligent university student. “In those days the degrees were awarded as a First, Second, Pass or Fail,” he said. “As I spent more time on the tennis court than with my books, my degree was a Second.”

After graduation he joined a British subsidiary of International Telephone & Telegraph, and spent the next three decades working for the company in Britain, Europe and the United States. It was during his stint in England that he met his future wife, Gwen Wong, a fellow engineer who worked on an upper floor.

In their landmark paper on fibre optics in 1966, Dielectricfibre Surface Waveguides for Optical Frequencies, Kao and Hockham noted that “a fibre of glassy material” and certain dimensions “represents a possible practical optical waveguide with important potential as a new form of communication medium”.

Kao received a half share of the 2009 Nobel Prize in physics; the other half was split between Willard S Boyle and George E Smith, both affiliated with Bell Laboratories at the time. They had invented a semiconductor sensor known as the charge-coupled device, the device behind digital photos and film.

The Royal Swedish Academy of Sciences said the work by all three men had collectively “built the foundation to our modern information society.”

Kao was knighted in 2010 and received an honorary degree from Princeton and many awards from engineering associations across the world. He was a professor and 2 A jubilant Charles Kao after being presented with the Grand Bauhinia Medal, Hong Kong’s highest honour, in 2010, the same year he was knighted

later vice chancellor at the Chinese University of Hong Kong, where he founded the department of electronics in 1970.

Kao is survived by his wife and two children, Amanda and Simon, who live in the United States, a spokeswoman for his Alzheimer’s foundation said.

“As one of the last wishes of Professor Kao, our foundation will keep up our work in supporting people with Alzheimer’s disease and their families,” Gwen Kao, the foundation’s chairwoman, said in a statement.

Kao said in the autobiographical sketch that his scientific breakthrough had not resulted from a “eureka” moment but rather from years of trial-and-error experiments. “Transmission of light through glass is an old, old idea,” he wrote.

In a 2004 interview with the IEEE History Centre, he was similarly self-effacing.

“I think it was a very respectable bit of detective work as well as good theory and good fundamentals,” he said of his contribution to the fibre optics field. “So there was really nothing spectacular.”

MIKE IVES The Scotsman welcomes obituaries and appreciations from contributors as well as suggestions of possible obituary subjects.

Please contact: Gazette Editor

The Scotsman, Level 7, Orchard Brae House, 30 Queensferry Road, Edinburgh EH4 2HS;

gazette@scotsman.com

nn“An eminent figure, Professor Kao is the pride of Hong Kong people”