Dr. Dennis Gábor
(b. 1900, Budapest - d. 1979, London)
Nobel Prize in 1971 for his investigation and development of holography.
What is Holography?
Holography dates from 1947, when Hungarian scientist Dennis
Gabor developed the theory of holography while working to improve the
resolution of an electron microscope. Gabor, who characterized his work
as "an experiment in serendipity," coined the term hologram from the
Greek words holos, meaning "whole," and gramma, meaning "message."
Further development in the field was stymied during the next decade
because light sources available at the time were not truly "coherent"
(monochromatic or one-color, from a single point, and of a single
wavelength).
This problem was solved in 1960 with the invention of the Laser. A laser
produces nearly coherent light and was found to be ideal for making crisp,
clear holographic images. Over the past three decades a number of other
mediums, such as x-rays, have been used to create holographic images. A
beam of coherent x-rays can be used to view particles the size of only one
or two atoms.
A hologram is quite simply the recording of interference patterns created
by two incident waves. Essentially, an interferometer. The drawing at right
is of an interference pattern created by two waves propogating from two
separate points. The regions of interference set up a standing wave which
can be used to expose film or other media reactive to the type of waves
being used. The film would then contain a three dimensional interference
pattern. For more, Visit A
History of Holography at Holophile.com
About Dr. Dennis Gábor
(adapted from his autobiography)
Dr. Dennis Gábor was born in Budapest, Hungary, on June 5, 1900, the
oldest son of Bertalan Gabor, director of a mining company, and his wife
Adrienne. His life-long love of physics started suddenly at the age of 15.
Fascinated by Abbe's theory of the microscope and by Gabriel Lippmann's method
of colour photography, he, with his late brother George built up a home
laboratory and began experimenting with wireless X-rays and radioactivity. He
entered the Technische Hochschule Berlin and acquired a Diploma in 1924 and his
Doctorate of Engineering in 1927 in electrical engineering. While there he
spent his free time working on physics at the University of Berlin. His
doctorate work was the development of one of the first high speed cathode ray
oscillographs and in the course of this, made the first iron-shrouded magnetic
electron lens. In 1927 he joined Siemens & Halske AG and made one of his
first successful inventions; the high pressure quartz mercury lamp with
superheated vapour and the molybdenum tape seal, since used in millions of
street lamps. In what Dennis calls his "first lesson in serendipity,"
he invented the mercury lamp while attempting to develop a cadmium lamp which
proved unsuccessful.
With the rise of Hitler In 1933, Dennis left Germany and after a short period in
Hungary went to depression stricken England. Finding a jobs as a foreigner was
very difficult. He eventually obtained employment with the British firm,
Thomson-Houston Co., in Rugby, on an inventor's agreement. His work on gas
discharge tubes gave him a foothold in the BTH Research Laboratory where he
remained until the end of 1948. Dennis writes that the years after the war were
the most fruitful. One his first papers was on communication theory. He also
developed a system of stereoscopic cinematography, and in the last year at BTH
carried out the basic experiments in holography, at that time called "wavefront
reconstruction".
On January 1, 1949 he joined the Imperial College of Science & Technology in
London, first as a Reader in Electronics, and later as Professor of Applied
Electron Physics, until his retirement in 1967. With post-graduate assistants,
he attacked many problems, almost always difficult ones, such as theelucidation
of Langmuirs Paradox, the inexplicably intense apparent electron interaction, in
low pressure mercury arcs. They also made a Wilson cloud chamber, in which the
velocity of particles became measurable by impressing on them a high frequency,
critical field, which produced time marks on the paths, at the points of maximum
ionisation. Other developments were: a holographic microscope; a new
electron-velocity spectroscope; an analogue computer which was a universal,
non-linear "learning" predictor, recognizer and simulator of time
series; a flat, thin colour television tube; and a new type of thermionic
converter. Theoretical work included communication theory, plasma theory,
magnetron theory, and a scheme of fusion.
After his retirement in 1967 he remained connected with the Imperial College as
a Senior Research Fellow and became Staff Scientist of CBS Laboratories,
Stamford, Conn. where he collaborated with the President, life-long friend, and father
of the color television, Dr. Peter C. Goldmark, in many new schemes of
communication and display. Though happy with his work, he begain to spend much
time on a new interest: the future of industrial civilization. He became more
and more convinced that a serious mismatch has developed between technology and
social institutions, and that inventive minds ought to consider social
inventions as their first priority. This conviction has found expression in
three books, Inventing the Future, 1963, Innovations, 1970, and The
Mature Society, 1972. He wrote, "Though I still have much unfinished
technological work on my hands, I consider this as my first priority in my
remaining years."
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