Wilhelm Kösters

Wilhelm Kösters (born April 25, 1876 in Münster ; † July 28, 1950 there ) was a German physicist and metrologist . From 1917 he was the managing director of the Physikalisch-Technische Reichsanstalt (PTR) in Berlin and from 1948 the first president of the Physikalisch-Technische Bundesanstalt (PTB) in Braunschweig .

Live and act

Kösters was born as the son of the master turner August Kösters and his wife Angela (née Ossendorf) in Münster. He studied physics, mathematics, chemistry and mineralogy in the cities of Münster, Greifswald and Bonn. He was there in 1899 with a thesis about the electrical charge electrolytically freshly prepared gases to Dr. phil. (Doctor of Science) PhD . He then worked briefly as an assistant for physics at the Technical University in Darmstadt and in the same year joined the “Imperial Standards Commission” (from 1918 “Reich Institute for Weights and Measures”) in Berlin-Charlottenburg. From 1917 Kösters was head of the length measurement laboratory, later Department 1 of the PTR, and developed an interference comparator for length measurements . In 1926 he developed the "Kösters comparator" named after him and in 1928 introduced standard lamps for interferential length measurements of gauge blocks with the help of this comparator. In 1960 the meter was defined on the basis of his joint research with Ernst Engelhard .

Kösters was married to Helene Emilie (née Terppe) and had three children with her.

Further commitment and awards

• Kösters had been a member of the International Committee for Weights and Measures (CIPM) since 1921 and represented Germany at the General Conference for Weights and Measures (CGPM). He was also the chairman of the metrology working committee in the German standards committee .

• In the 1930s he campaigned for the establishment of an International Organization of Legal Metrology (OIML), which was not implemented until 1955 after his death.

• In Stuttgart he became Prof. Dr.-Ing. E. h. and was a member of the Braunschweigische Wissenschaftliche Gesellschaft (BWG).

Fonts (selection)

• About the electric charge of electrolytically freshly produced gases (= dissertation, University of Bonn). JA Barth, Leipzig 1899, doi: 10.1002 / andp.18993050903 .
• The large comparator of the Imperial Standard Calibration Commission. Julius Springer, Berlin 1912, OCLC 162678216 , pp. 85-109.
• A new interference comparator f. direct wavelength connection. In: Journal for Precision Mechanics and Precision. No. 34. Verlag für Technische Literatur, Mühlhausen 1926, pp. 55-59.
• Use of the interference for measurement purposes. In: Handbook of physical optics. Volume 1. JA Barth, Leipzig 1926/27, OCLC 728387786 .

literature

• Friedrich Bayer-Helms:  Kösters, Wilhelm. In: New German Biography (NDB). Volume 12, Duncker & Humblot, Berlin 1980, ISBN 3-428-00193-1 , p. 406 f. ( Digitized version ).

Web links

• With light metering (PDF; 450 kB) on ptb.de.
• Wilhelm Kösters on ptb.de (with photo)
• City chronicle: July 28, 1950 on braunschweig.de (death report)

Individual evidence

1. ↑ 1948 - Wilhelm Kösters becomes PTB President. In: PTR / PTB: 125 years of metrological research p. 33. (PDF; 4.5 MB) on ptb.de, accessed on December 29, 2015.
2. ^ Friedrich Bayer-Helms:  Kösters, Wilhelm. In: New German Biography (NDB). Volume 12, Duncker & Humblot, Berlin 1980, ISBN 3-428-00193-1 , p. 406 f. ( Digitized version ).
3. ↑ 1917 - Wilhelm Kösters heads the length measurement laboratory and 1926 - Kösters comparator p. 19/25. in PTR / PTB: 125 Years of Metrological Research (PDF; 4.5 MB) on ptb.de, accessed on December 29, 2015.
4. ↑ With light metering (PDF; 450 kB) on ptb.de, accessed on September 27, 2013.
5. ^ Resolutions of the CGPM: 11th meeting (October 11-20, 1960) at bipm.org, accessed September 27, 2013 (English, French).
6. ^ The history of the International Organization of Legal Metrology. ( Memento of July 3, 2009 in the Internet Archive ) (PDF) at oiml.org, accessed on September 27, 2013.