Oskar Heil (20 March 1908, in
Langwieden – 15 May 1994,
San Mateo, California
San Mateo ( ; ) is a city in San Mateo County, California, on the San Francisco Peninsula. About 20 miles (32 km) south of San Francisco, the city borders Burlingame to the north, Hillsborough to the west, San Francisco Bay and Foster C ...
) was a German electrical engineer and inventor. He studied
physics,
chemistry
Chemistry is the science, scientific study of the properties and behavior of matter. It is a natural science that covers the Chemical element, elements that make up matter to the chemical compound, compounds made of atoms, molecules and ions ...
,
mathematics
Mathematics is an area of knowledge that includes the topics of numbers, formulas and related structures, shapes and the spaces in which they are contained, and quantities and their changes. These topics are represented in modern mathematics ...
, and
music at the
Georg-August University of Göttingen and was awarded his
PhD PHD or PhD may refer to:
* Doctor of Philosophy (PhD), an academic qualification
Entertainment
* '' PhD: Phantasy Degree'', a Korean comic series
* ''Piled Higher and Deeper'', a web comic
* Ph.D. (band), a 1980s British group
** Ph.D. (Ph.D. albu ...
in 1933, for his work on molecular spectroscopy.
Personal life
At the
Georg-August University in
Göttingen, Oskar Heil met Agnesa Arsenjewa (Агнесса Николаевна Арсеньева, 1901–1991), a promising young Russian physicist who also earned her PhD there. They married in
Leningrad, the
Soviet Union in 1934.
Together they moved to the
United Kingdom to work in the
Cavendish Laboratory
The Cavendish Laboratory is the Department of Physics at the University of Cambridge, and is part of the School of Physical Sciences. The laboratory was opened in 1874 on the New Museums Site as a laboratory for experimental physics and is named ...
, University of Cambridge. While on a trip to Italy, they co-wrote a pioneering paper on the generation of microwaves which was published in Germany in the ''Zeitschrift für Physik'' (i.e., ''Journal on Physics'') in 1935. Agnesa subsequently returned to Russia to pursue this work further at the Leningrad Physico-Chemical Institute with her husband. However, he then returned to the UK alone; Agnesa, working in what had by then become a highly sensitive subject, was possibly not allowed to leave. Back in Britain, Oskar Heil worked for
Standard Telephones and Cables.
At the onset of the
Second World War he returned to Germany via Switzerland. During the war Heil worked on a
microwave generator for the
C. Lorenz AG
C. Lorenz AG (1880–1958) was a German electrical and electronics firm primarily located in Berlin. It innovated, developed, and marketed products for electric lighting, telegraphy, telephony, radar, and radio. It was acquired by ITT in 1930 and ...
in
Berlin-Tempelhof
Tempelhof () is a locality of Berlin within the borough of Tempelhof-Schöneberg. It is the location of the former Tempelhof Airport, one of the earliest commercial airports in the world. The former airport and surroundings are now a park called ...
.
In 1947 Heil was invited to the USA. After doing scientific work for
Eitel McCullough and later the
Varian Eimac division in San Carlos from 1955 until 1983, he founded his own company called ''Heil Scientific Labs Inc.'' in 1963 in
Belmont, California. Agnesa remained in the Soviet Union until her death in 1991.
Microwave vacuum tube
Oskar Heil and Agnesa Arsenjewa-Heil in their pioneering paper developed the concept of the velocity-modulated tube, in which a beam of electrons could be made to form into "bunches" and thereby generate with reasonable efficiency radio waves of considerably higher frequency and power than were possible with conventional vacuum tubes/thermionic valves. This resulted in production of the "Heil tube", the first truly-practicable microwave generator, which slightly predated the (independent) invention of the
klystron and subsequently the
reflex klystron based on the same operating principle. These devices were a significant milestone in the development of microwave technology (particularly
radar), and velocity-modulated tubes are still very much in use at the present day.
Field-effect transistor
Heil is mentioned as the inventor of an early
transistor-like device (see also
History of the transistor), based on several patents that were issued to him.
JFETS: The New Frontierstates:
:"Field-effect transistors (FETs) have been around for a long time; in fact, they were invented, at least theoretically, before the bipolar transistors. The basic principle of the FET has been known since
J.E. Lilienfeld’s US patent from 1930, and Oscar Heil described the possibility of controlling the resistance in a semiconducting material with an electric field in a British patent in 1935."
Air Motion Transformer
He also invented the "air-motion transformer" audio speaker technology made famous by the amt1 speaker of ESS in the early 1970s.
"Heil air motion transformer" , which may still be available in cached form.
The amt voice coil membrane is made of a polyethylene sheet, embossed with conductive aluminum strips. It is equivalent in surface area to a conventional 7-inch cone type mid-range driver, but is accordion-folded down to less than a 2-inch grouping for point-source dispersion. The low-mass membrane sheet is suspended within a quadratic magnetic housing, concentrating an intense field around the diaphragm. When signal current passes through the aluminum strips, the ensuing bellows-like motion of the folded pleats moves air five times faster than a conventional cone driver. This rapid acceleration of air-motion is claimed to provide enhanced sound reproduction, including high dynamic range and over an extremely broad frequency range.
References
* Agnes Arsenjewa, ''Über den Einfluß des Röntgenlichtes auf die Absorptionsspektra der Alkalihalogenidphosphore'', PhD thesis, 1929.
* Oskar Heil, ''Auslöschung und Überführung von Resonanzserienspektren ins Bandenspektrum durch Gaszusatz'', PhD thesis, 1932.
* A. Arsenjewa-Heil and O. Heil, ''Eine neue Methode zur Erzeugung kurzer, ungedämpfter, elektromagnetischer Wellen großer Intensität'', Zeitschrift für Physik, Vol. 95, Nos. 11-12 (November 1935), pp. 752–762.
External links
{{DEFAULTSORT:Heil. Oskar
1908 births
1994 deaths
German electrical engineers
20th-century German physicists
University of Göttingen alumni
People from Kaiserslautern (district)
Engineers from Rhineland-Palatinate