Otto Lehmann (13 January 1855 in

Konstanz Konstanz ( , , , ), traditionally known as Constance in English, is a college town, university city with approximately 83,000 inhabitants located at the western end of Lake Constance in the Baden-Württemberg state of south Germany. The city ho ...

Germany Germany, officially the Federal Republic of Germany, is a country in Central Europe. It lies between the Baltic Sea and the North Sea to the north and the Alps to the south. Its sixteen States of Germany, constituent states have a total popu ...

– 17 June 1922 in

Karlsruhe Karlsruhe ( ; ; ; South Franconian German, South Franconian: ''Kallsruh'') is the List of cities in Baden-Württemberg by population, third-largest city of the States of Germany, German state of Baden-Württemberg, after its capital Stuttgart a ...

) was a German

physicist A physicist is a scientist who specializes in the field of physics, which encompasses the interactions of matter and energy at all length and time scales in the physical universe. Physicists generally are interested in the root or ultimate cau ...

and "father" of

liquid crystal Liquid crystal (LC) is a state of matter whose properties are between those of conventional liquids and those of solid crystals. For example, a liquid crystal can flow like a liquid, but its molecules may be oriented in a common direction as i ...

Life

Otto was the son of Franz Xavier Lehmann, a mathematics teacher in the Baden-Wurtemberg school system, with a strong interest in

microscope A microscope () is a laboratory equipment, laboratory instrument used to examine objects that are too small to be seen by the naked eye. Microscopy is the science of investigating small objects and structures using a microscope. Microscopic ...

s. Otto learned to experiment and keep records of this findings. Between 1872 and 1877, Lehmann studied

natural science Natural science or empirical science is one of the branches of science concerned with the description, understanding and prediction of natural phenomena, based on empirical evidence from observation and experimentation. Mechanisms such as peer ...

s at the University of Strassburg and obtained the Ph.D. under crystallographer Paul Groth. Otto used

polarizer A polarizer or polariser is an optical filter that lets light waves of a specific polarization (waves), polarization pass through while attenuation, blocking light waves of other polarizations. It can filter a beam of light of undefined or mixed ...

s in a microscope so that he might watch for

birefringence Birefringence, also called double refraction, is the optical property of a material having a refractive index that depends on the polarization and propagation direction of light. These optically anisotropic materials are described as birefrin ...

appearing in the process of crystallization. Initially becoming a school teacher for physics, mathematics and chemistry in

Mülhausen Mulhouse (; ; Alsatian language, Alsatian: ''Mìlhüsa'' ; , meaning "Mill (grinding), mill house") is a France, French city of the European Collectivity of Alsace (Haut-Rhin department, in the Grand Est region of France). It is near the Fran ...

( Alsace-Lorraine), he started university teaching at the

RWTH Aachen University RWTH Aachen University (), in German ''Rheinisch-Westfälische Technische Hochschule Aachen'', is a German public research university located in Aachen, North Rhine-Westphalia, Germany. With more than 47,000 students enrolled in 144 study prog ...

in 1883. In 1889, he succeeded

Heinrich Hertz Heinrich Rudolf Hertz (; ; 22 February 1857 – 1 January 1894) was a German physicist who first conclusively proved the existence of the electromagnetic waves predicted by James Clerk Maxwell's equations of electromagnetism. Biography Heinri ...

as head of the Institute of Physics in

. Lehmann received a letter from Friedrich Reinitzer asking for confirmation of some unusual observations. As Dunmur and Sluckin(2011) say :It was Lehmann's jealously guarded and increasingly prestigious microscope, not yet available off the shelf, which had attracted Reinitzer's attention. With Reinitzer's peculiar double-melting liquid, a problem in search of a scientist had met a scientist in search of a problem. The article "On Flowing Crystals" that Lehmann wrote for

Zeitschrift für Physikalische Chemie A magazine is a periodical literature, periodical publication, print or digital, produced on a regular schedule, that contains any of a variety of subject-oriented textual and visual content (media), content forms. Magazines are generally fin ...

addresses directly the question of

phase of matter In the physical sciences, a phase is a region of material that is chemically uniform, physically distinct, and (often) mechanically separable. In a system consisting of ice and water in a glass jar, the ice cubes are one phase, the water is a ...

involved, and leaves in its wake the science of

s. Lehmann was an ''unsuccessful nominee'' for a

Nobel Prize The Nobel Prizes ( ; ; ) are awards administered by the Nobel Foundation and granted in accordance with the principle of "for the greatest benefit to humankind". The prizes were first awarded in 1901, marking the fifth anniversary of Alfred N ...

from 1913 to 1922.

Work

*Selbstanfertigung physikalischer Apparate. Leipzig 1885. *Molekularphysik (i.e. ''Molecular physics''). 2 Bde, Leipzig 1888/89. *Die Kristallanalyse (i.e. ''The Analysis of Crystals''). Leipzig 1891. *Elektricität und Licht (i.e. ''Electricity and Light''). Braunschweig 1895. *Flüssige Krystalle (i.e. ''Liquid Crystals''). Leipzig 1904. *Die scheinbar lebenden Krystalle. Eßlingen 1907. *Die wichtigsten Begriffe und Gesetze der Physik. Berlin 1907. *Flüssige Kristalle und ihr scheinbares Leben. Forschungsergebnisse dargestellt in einem Kinofilm. Voss, Leipzig 1921.

References

* David Dunmur & Tim Sluckin (2011), ''Soap, Science, and Flat-screen TVs: a history of liquid crystals'', pp 20–7,

Oxford University Press Oxford University Press (OUP) is the publishing house of the University of Oxford. It is the largest university press in the world. Its first book was printed in Oxford in 1478, with the Press officially granted the legal right to print books ...

. * Michel Mitov (2014), ''Liquid-Crystal Science from 1888 to 1922: Building a Revolution'', in ''ChemPhysChem'', vol. 15, pp 1245–1250. {{DEFAULTSORT:Lehmann, Otto 1855 births 1922 deaths 19th-century German physicists People from Konstanz People from the Grand Duchy of Baden University of Strasbourg alumni Academic staff of the Karlsruhe Institute of Technology Academic staff of RWTH Aachen University 20th-century German physicists

Life

Work

See also

References