Hans Erich (Eric) Hollmann (4 November 1899 – 19 November 1960) was a German electronic specialist who made several breakthroughs in the development of

radar Radar is a detection system that uses radio waves to determine the distance (''ranging''), angle, and radial velocity of objects relative to the site. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, w ...

. Hollmann was born in

Solingen Solingen (; li, Solich) is a city in North Rhine-Westphalia, Germany. It is located some 25 km east of Düsseldorf along the northern edge of the region called Bergisches Land, south of the Ruhr area, and, with a 2009 population of 161,366, ...

Germany Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in Europe after Russia, and the most populous member state of the European Union. Germany is situated betwe ...

. He became interested in radio and even as a teenager subscribed to the technical magazines of the day. Late in

World War I World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, the United States, and the Ottoman Empire, with fightin ...

he became a prisoner of war of the French and did not return to Germany until 1920. He then studied at the Technical University at

Darmstadt Darmstadt () is a city in the States of Germany, state of Hesse in Germany, located in the southern part of the Frankfurt Rhine Main Area, Rhine-Main-Area (Frankfurt Metropolitan Region). Darmstadt has around 160,000 inhabitants, making it th ...

until he received his doctorate in 1928. Hollmann's doctoral research included the development of an ultra-short-wave transmitter and receiver for centimetre and decimetre waves. This gained the attention of ''Telefunken'', and ultimately led to their development of the first microwave telecommunication system. In 1930 Hollmann moved to the Heinrich-Hertz Institute for Oscillatory Research in Berlin. There he continued studies in microwaves and cathode ray tubes and also worked on the ionosphere research and radio astronomy. In 1933 Hollmann became a lecturer at the Technical University in Berlin. In January 1934, Hans-Karl von Willisen and Paul-Günther Erbslöh started a company called Gesellschaft für elektroakustische und mechanische Apparate (GEMA). With Hollmann as a consultant, GEMA built a system using interference detection in the autumn of 1934. It operated at 50 cm wavelength and could detect ships up to 10 km distance. By 1935, they used pulse-modulation, allowing measurement of range (distance to the target), and developed the technology into two applications. For naval use, the ''

Seetakt Seetakt was a shipborne radar developed in the 1930s and used by Nazi Germany's ''Kriegsmarine'' during World War II. Development In Germany during the late 1920s, Hans Hollmann began working in the field of microwaves, which were to later becom ...

'' system used a wavelength of 80 cm. A land based version at 120 cm wavelength was also developed as ''

Freya In Norse paganism, Freyja (Old Norse "(the) Lady") is a goddess associated with love, beauty, fertility, sex, war, gold, and seiðr (magic for seeing and influencing the future). Freyja is the owner of the necklace Brísingamen, rides a chario ...

''.

Telefunken Telefunken was a German radio and television apparatus company, founded in Berlin in 1903, as a joint venture of Siemens & Halske and the ''Allgemeine Elektrizitäts-Gesellschaft'' (AEG) ('General electricity company'). The name "Telefunken" app ...

set up a radar business in 1933 based on Hollmann's work and developed a much shorter-range gun-laying system called ''

Würzburg Würzburg (; Main-Franconian: ) is a city in the region of Franconia in the north of the German state of Bavaria. Würzburg is the administrative seat of the ''Regierungsbezirk'' Lower Franconia. It spans the banks of the Main River. Würzburg is ...

''. During

World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposin ...

, ''Freya'' and ''Würzburg'' worked in pairs. ''Freya'' would spot the incoming aircraft while the ''Würzburg'' calculated the distance and height. In 1935, Hollmann wrote two books on microwaves, ''Physics and Technique of Ultra-short Waves'' and ''Seeing with Electromagnetic Waves'', which were the inspiration for the development of centimetre radar in other countries despite some

censorship Censorship is the suppression of speech, public communication, or other information. This may be done on the basis that such material is considered objectionable, harmful, sensitive, or "inconvenient". Censorship can be conducted by governments ...

of their contents. During the war he supervised many research institutes in occupied countries and saved many scientists from being deported to Germany. He established the Laboratory for High-Frequency Engineering and Ultrasound in

Lichterfelde Lichterfelde may refer to: * Lichterfelde (Berlin), a locality in the borough of Steglitz-Zehlendorf in Berlin, Germany * Lichterfelde West, an elegant residential area in Berlin * Lichterfelde, Saxony-Anhalt, a municipality in the Stendhal Distric ...

Berlin Berlin ( , ) is the capital and largest city of Germany by both area and population. Its 3.7 million inhabitants make it the European Union's most populous city, according to population within city limits. One of Germany's sixteen constitue ...

. Part of their work involved making transmitters for the Navy. Here he brought in

Max Bense Max Bense (7 February 1910 in Strasbourg – 29 April 1990 in Stuttgart) was a German philosopher, writer, and publicist, known for his work in philosophy of science, logic, aesthetics, and semiotics. His thoughts combine natural sciences, art, a ...

. At this time there was speculation about a future possibility of teleporting human beings from Germany to

California California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territori ...

. His home and his laboratory were destroyed during the war. After the war he was not allowed to work on microwaves but he turned his attention to a wide range of other fields in electronics. In 1947 he accepted an offer from the US Government to work for

NASA The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research. NASA was established in 1958, succeeding t ...

. In 1949 he sent Bense a copy of

Norbert Wiener Norbert Wiener (November 26, 1894 – March 18, 1964) was an American mathematician and philosopher. He was a professor of mathematics at the Massachusetts Institute of Technology (MIT). A child prodigy, Wiener later became an early researcher i ...

's '' Cybernetics: Or Control and Communication in the Animal and the Machine'' (1948), stimulating the latter's interest in

cybernetics Cybernetics is a wide-ranging field concerned with circular causality, such as feedback, in regulatory and purposive systems. Cybernetics is named after an example of circular causal feedback, that of steering a ship, where the helmsperson m ...

. He was married to Gisela Schimmelbusch and had three children. He died in

Los Angeles Los Angeles ( ; es, Los Ángeles, link=no , ), often referred to by its initials L.A., is the largest city in the state of California and the second most populous city in the United States after New York City, as well as one of the world' ...

in 1960.

References

External links

Biography on his sixtieth birthday
{{DEFAULTSORT:Hollmann, Hans 1899 births 1960 deaths 20th-century German physicists Radar pioneers Operation Paperclip People from Solingen German emigrants to the United States