|Born||13 January 1855|
|Died||17 June 1922 (aged 67)|
|Alma mater||University of Strassburg|
|Known for||Flowing crystals|
|Institutions||Aachen & Karlsruhe|
|Doctoral advisor||Paul Heinrich von Groth|
Otto was the son of Franz Xavier Lehmann, a mathematics teacher in the Baden-Wurtemberg school system, with a strong interest in microscopes. Otto learned to experiment and keep records of this findings. Between 1872 and 1877, Lehmann studied natural sciences at the University of Strassburg and obtained the Ph.D. under crystallographer Paul Groth. Otto used polarizers in a microscope so that he might watch for birefringence appearing in the process of crystallization.
Initially becoming a school teacher for physics, mathematics and chemistry in Mülhausen (Alsace-Lorraine), he started university teaching at the RWTH Aachen University in 1883. In 1889, he succeeded Heinrich Hertz as head of the Institute of Physics in Karlsruhe.
Lehmann received a letter from Friedrich Reinitzer asking for confirmation of some unusual observations. As Dunmur and Sluckin(2011) say
The article "On Flowing Crystals" that Lehmann wrote for Zeitschrift für Physikalische Chemie addresses directly the question of phase of matter involved, and leaves in its wake the science of liquid crystals.
Lehmann was an unsuccessful nominee for a Nobel Prize from 1913 to 1922.