- Person
- Dennis Gabor
- Lived
- 1900–1979
- Field
- Physics, engineering
- From
- Hungarian-British
The story
Dennis Gabor was born into a Jewish family in Budapest in 1900. The family converted to Lutheranism, but when Hitler came to power in 1933 Gabor, then an engineer at Siemens in Berlin, was considered Jewish and left Germany. In 1934 he found work at the British Thomson-Houston company in Rugby.
There he was trying to improve the electron microscope, which could not resolve individual atoms because electron lenses are so imperfect. After long thought, he later wrote, a solution dawned on him one fine day at Easter 1947: take a bad electron picture that contains the whole information, then correct it by optical means. An ordinary photograph records only the brightness of light. Gabor proposed recording the light waves themselves by letting light from an object interfere with a clean reference wave. The resulting pattern of fringes looks nothing like the object, but shining a similar wave back through it rebuilds the original waves and a full three-dimensional image. He called the pattern a hologram, from the Greek holos, whole. He filed a patent in December 1947 and in 1948, with his assistant Ivor Williams, made the first holograms using filtered mercury light.
The technique needed perfectly coherent light, which did not yet exist, and it lay mostly dormant until the laser was invented in 1960. In 1962 Yuri Denisyuk in the Soviet Union and Emmett Leith and Juris Upatnieks in Michigan made the first laser holograms of three-dimensional objects, and holography spread to thousands of laboratories.
Today Gabor’s invention is in most people’s wallets. Security holograms are copied from master holograms that are very hard to make, so they are used against forgery on banknotes in many countries, including the euro area, the United Kingdom, Canada and Japan, and on credit cards, passports and identity cards. Holographic interferometry, which compares holograms of an object before and after it is stressed, measures movements smaller than a wavelength of light and is widely used to study strain and vibration in engineering structures. Gabor received the 1971 Nobel Prize in Physics for the invention and development of the holographic method.
Why it matters
Holography protects money and identity documents against forgery worldwide and gives engineers a precise way to measure stress and vibration.
About Dennis Gabor
Hungarian-born engineer who fled Nazi Germany and in Britain invented holography, now used in the security holograms on banknotes, cards and passports and to measure stress in engineering.
Sources
- Holography, 1948–1971, Nobel Lecture NobelPrize.org
- Holography Wikipedia
- Dennis Gabor Wikipedia
- Dennis Gabor, Biographical NobelPrize.org
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