Dennis Gabor

Hungarian British electrical engineer

• Born: June 5, 1900
• Birthplace: Budapest, Hungary
• Died: February 8, 1979
• Place of death: London, England

Known as the “father of holography,” Gabor was awarded more than one hundred patents for inventions dealing with communication theory, physical optics, plasma theory, magnetron theory, and television. Gabor’s invention of holography, a lensless method for producing three-dimensional images of objects, has myriad practical applications.

Primary fields: Optics; physics

Primary invention: Holography

Early Life

Dennis Gabor (GAH-bohr) was the oldest of three sons born to Bertalan, director of the Hungarian General Coal Mines, and Adrienne Gabor, a former actress. In his youth, Gabor became very interested in scientific investigations and conducted several experiments with his brother George that involved the use of X rays and radioactivity in a home laboratory that they had built together. He loved to explore the inner workings of any thing around him. By age eleven, Gabor had received his first patent for a carousel that employed tethered airplanes.

After serving in the Austro-Hungarian army during World War I, Gabor began the pursuit of a degree in mechanical engineering at Budapest Technical University in 1918. Upon a second request that he serve in the army, in 1920, he left Hungary and traveled to Germany, where he entered the Technical University of Berlin in 1921. While there, he earned a degree in electrical engineering (1924) and his doctorate in the same field (1927). His doctoral dissertation focused on the development of one of the first high-speed cathode-ray oscilloscopes and the invention of the first iron-covered magnetic electron lenses.

During his school years in Berlin, Gabor often visited the University of Berlin to increase his knowledge about physics. He attended lectures and seminars presented by Max Planck, Albert Einstein, Max von Laue, and other prominent physicists of the time. Upon completion of his doctorate, Gabor was employed as a research engineer by Siemens and Halske in Berlin. While working there, he made one of his first successful inventions, a high-pressure quartz-mercury lamp that used superheated vapor and a molybdenum tape seal. Upon Adolf Hitler’s rise to power in 1933, Gabor moved to England, where he worked for British Thomson-Houston (BTH) in Rugby, Warwickshire, for the next fifteen years. In 1936, he married Marjorie Louise Butler, the daughter of Joseph and Louise Butler. The couple had no children.

Life’s Work

Due to Gabor’s expertise with gas discharge tube technology, he was assigned to work in the BTH Research Laboratory in 1933. His major research work focused on improving the resolution of the electron microscope. In 1946, he published some of the results of his research in The Electron Microscope: Its Development, Present Performance, and Future Possibilities.

By 1947, Gabor thought that he had finally solved the resolution problem. He decided that the unclear picture obtained from an electron microscope contained the complete information about the object under investigation. His idea was to clarify the distorted electron image using optical methods to recover all the information about the object. Gabor suggested splitting the electron beam into two beams, reflecting one of the beams off the object of interest and the other off a mirror. When the resultant beams were recombined on a piece of photographic film, an interference pattern would result because the two beams traveled different path lengths.

Gabor proved mathematically that when light was shone back through the unclear filmed image, a three-dimensional picture of the object would be reconstructed. He termed the process “wavefront reconstruction,” and coined the term “hologram,” meaning “whole message,” as the name for the unclear image captured on film. Using a mercury lamp and directing its light through a pinhole, Gabor produced some inexact holograms, which proved the feasibility of his method. He published his initial results about holography in Nature in 1948, followed by papers on optical imaging and holography in Proceedings of the Royal Society in 1949 and in Proceedings of the Physical Society in 1951.

On January 1, 1949, Gabor left BTH and began teaching electronics and applied physics at the Imperial College of Science and Technology at the University of London. During his eighteen years there, with the assistance of several graduate students, he developed a number of inventions that included a high-frequency Wilson cloud chamber to identify elementary particles; a holographic microscope; an analog computer; an electron-velocity spectroscope; a new type of thermionic converter; a flat, thin color television tube; and a stereoscopic cinematography system that he had initially worked on at BTH. Gabor and some postdoctoral students clarified the Langmuir paradox by explaining why intense electron interactions occur in plasmas.

In addition to his inventions, Gabor also conducted research on how humans communicate and hear, which led to the theory of granular synthesis. In 1956, he was nominated as a fellow of the Royal Society. Two years later, he was promoted to a professor of applied physics at the Imperial College, where he remained until his retirement in 1967. Gabor was honored with the Thomas Young Medal of the Physical Society of London as well as the Cristoforo Colombo Prize of the International Institute for Communications in Genoa, Italy, in 1967. One year later, he was awarded both the Albert Michelson Medal of the Franklin Institute of Philadelphia and the Rumford Medal of the Royal Society.

During his retirement years, Gabor continued to work as a senior research fellow with the Imperial College and as a staff scientist for CBS Laboratories in Stamford, Connecticut, on problems associated with communication. He also spent a lot of time vacationing at his private villa near Rome, Italy, where he enjoyed sunbathing, reading, writing, and singing. In 1970, he was honored as a Commander of the Order of the British Empire and also received the Medal of Honor of the Institute of Electrical and Electronics Engineers. One year later, he was awarded the Holweck Prize of the French Physical Society. That same year, he received the Nobel Prize in Physics for his invention of holography.

During the 1970’s, Gabor became more and more concerned with the function of science and technology in society and the future of an industrial civilization. He strongly believed that inventors should consider social inventions and advancements as their top priority. Some of his insights into the social implications of technological advancements led him to publish Innovations: Scientific, Technological, and Social (1970), The Mature Society: A View of the Future (1972), and Proper Priorities of Science and Technology (1972). Gabor died in London on February 8, 1979.

Impact

Gabor’s inventive philosophy is encapsulated in his famous statement, “You can’t predict the future, but you can invent it.” He is a prime example of a scientist and inventor who relentlessly and methodically brought his ideas to fruition even when the final practical outcome was something quite different from his initial pursuit. He had his first encounter with serendipity in the late 1920’s, when, in his attempt to invent a cadmium lamp, he instead invented the mercury lamp, which was used in thousands of street lamps. His second encounter with serendipity came about twenty years later, when, in trying to make improvements to the electron microscope in order to resolve atomic lattices and see individual atoms, he invented the process of holography.

Since there were no coherent, monochromatic light sources available when Gabor invented holography, his initial demonstrations were not very impressive, but they verified that the process worked. The full impact of his inventive genius was not realized until the early 1960’s after the laser was invented. Since the laser provided an intense, coherent, monochromatic light source, clear three-dimensional images using Gabor’s holographic method were being produced by 1962. Since that time, holograms have been used increasingly in myriad ways that include applications in medicine, cartography, computer information storage, and advertising, and on credit cards to prevent counterfeiting.

During his career, Gabor was awarded more than one hundred patents and published numerous papers and books. In his honor, the International Society for Optical Engineering presents the annual Dennis Gabor Award to recognize significant accomplishments in diffractive wavefront technology, particularly holography, while the Hungarian Academy of Sciences presents the International Dennis Gabor Award each year to young scientists who make important contributions in applied physics and technology.

Bibliography

Caulfield, Henry John, Jacques Ludman, and Juanita Riccobono, eds. Holography for the New Millennium. New York: Springer-Verlag, 2002. A good review of the historical development of holography. Two chapters are devoted to a discussion of the frontiers of holographic imaging, including color holograms and stereographic movies. Several chapters describe novel methods of producing and viewing holographic images, including computer-generated holograms. New applications of holography are discussed that include improving the efficiency of solar cells and information storage and processing.

Heckman, Philip. The Magic of Holography. New York: Atheneum, 1986. Heckman presents a history of the developments in holography from important early discoveries in the field of optics to the first hologram produced by Gabor. Potential future applications of holography and their practical implications are explored.

Johnston, Sean. Holographic Visions: A History of New Science. New York: Oxford University Press, 2006. The historical development of holography is traced from the initial work of Gabor into the twenty-first century. Photographs of some early holograms and the scientific pioneers in this field are included. Gabor’s insightful and relentless work led to a new field of discovery that eventually reached maturity.

Kuo, Chung J., and Meng Hua Tsai, eds. Three-Dimensional Holographic Imaging. New York: Wiley, 2002. Presents a comprehensive survey of the concepts of three-dimensional holographic imaging and the techniques used in a variety of scientific and engineering applications. Starting with the holographic process invented by Gabor, world-renowned experts in the field provide discussions and examples of the principles and applications of holography that include holographic design and construction of advanced imaging systems.

Saxby, Graham. Practical Holography. Bristol, England: Institute of Physics, 2004. Techniques for producing holographic images—from simple single-beam holograms to multicolor art holograms to complex holographic stereograms—are detailed. The principles of holography as developed by Gabor are described, as well as techniques for doing holography, how to set up a holographic laboratory, development of the images, and the methods for displaying holograms. Applications to an array of scientific fields are included.