Ernst Abbe

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Ernst Abbe

HonFRMS
Born(1840-01-23)23 January 1840
Died14 January 1905(1905-01-14) (aged 64)
NationalityGerman
Alma mater
Known for
Scientific career
FieldsPhysics
Optical engineering
InstitutionsUniversity of Jena
Doctoral advisor
Doctoral studentsHeinrich Friedrich Weber
Other notable studentsGottlob Frege

Ernst Karl Abbe

HonFRMS (23 January 1840 – 14 January 1905) was a German businessman, optical engineer, physicist, and social reformer. Together with Otto Schott and Carl Zeiss, he developed numerous optical instruments. He was also a co-owner of Carl Zeiss AG
, a German manufacturer of scientific microscopes, astronomical telescopes, planetariums, and other advanced optical systems.

Personal life

Else Snell

Abbe was born 23 January 1840 in

Frankfurt (an association of citizens interested in physics and chemistry that was founded by Johann Wolfgang von Goethe in 1824 and still exists today).[4] On 8 August 1863 he qualified as a university lecturer at the University of Jena. In 1870, he accepted a contract as an associate professor of experimental physics, mechanics and mathematics in Jena.[1][5] In 1871, he married Else Snell, daughter of the mathematician and physicist Karl Snell, one of Abbe's teachers,[nb 1] with whom he had two daughters.[2] He attained full professor status by 1879.[2] He became director of the Jena astronomical and meteorological observatory in 1878.[5][nb 2] In 1889, he became a member of the Bavarian Academy of Sciences and Humanities. He also was a member of the Saxon Academy of Sciences. He was relieved of his teaching duties at the University of Jena in 1891. Abbe died 14 January 1905 in Jena.[1] He was an atheist.[6]

Life work

Microscope by Carl Zeiss (1879) with optics by Abbe
The resolution limit formula engraved in an Ernst Abbe memorial in Jena, Germany
German stamp of 1968
transparent material's variation of refractive index with wavelength and Abbe's criterion, which tests the hypothesis, that a systematic trend exists in a set of observations (in terms of resolving power this criterion stipulates that an angular separation cannot be less than the ratio of the wavelength to the aperture diameter, see angular resolution).[9] Already a professor in Jena, he was hired by Carl Zeiss
to improve the manufacturing process of optical instruments, which back then was largely based on trial and error.

Abbe was the first to define the term numerical aperture,[10] as the sine of the half angle multiplied by the refractive index of the medium filling the space between the cover glass and front lens.

Abbe is credited by many for discovering the resolution limit of the microscope, and the formula (published in 1873)

 

 

 

 

(Eq. 1)

although in a publication in 1874,

University of Berlin, which he refused due to his ties to Zeiss.[4] Abbe was in the camp of the wide aperturists, arguing that microscopic resolution is ultimately limited by the aperture of the optics, but also argued that depending on application there are other parameters that should be weighted over the aperture in the design of objectives. In Abbe's 1874 paper, titled "A Contribution to the Theory of the Microscope and the nature of Microscopic Vision",[12]
Abbe states that the resolution of a microscope is inversely dependent on its aperture, but without proposing a formula for the resolution limit of a microscope.

In 1876, Abbe was offered a partnership by Zeiss and began to share in the considerable profits.

Fizeau, in 1884.[2] Abbe, Zeiss, Zeiss' son, Roderich Zeiss, and Otto Schott formed, in 1884, the Jenaer Glaswerk Schott & Genossen. This company, which in time would in essence merge with Zeiss Optical Works, was responsible for research and production of 44 initial types of optical glass.[8] Working with telescopes, he built an image reversal system in 1895.[2]

In order to produce high quality objectives, Abbe made significant contributions to the diagnosis and correction of

Hans Busch used them to work on the development of the electron microscope.[4]

During his association with

Carl Zeiss Foundation for research in science.[2] The aim of the foundation was "to secure the economic, scientific, and technological future and in this way to improve the job security of their employees."[8] He made it a point that the success of an employee was based solely on their ability and performance, not on their origin, religion, or political views.[8] In 1896, he reorganized the Zeiss optical works into a cooperative with profit-sharing.[5] His social views were so respected as to be used by the Prussian state as a model and idealized by Alfred Weber in the 1947 book Schriften der Heidelberger Aktionsgruppe zur Demokratie und Zum Freien Sozialismus (Writings of the Heidelberg Action Group on Democracy and Free Socialism).[15]

The crater Abbe on the Moon was named in his honour.[16]

Bibliography

Abbe was a pioneer in optics, lens design, and microscopy, and an authority of his time. He left us with numerous publications of his findings, inventions, and discoveries. Below is a list of publications he authored including many links to the scanned Google Books pages.

See also

Notes

  1. ^ Some sources give his wife's name as Elisabeth.[2]
  2. ^ The dates of his job appointments at the University of Jena, including his appointment as director of the Jena Observatory has some uncertainty, as sources give different dates, as following. 1870: assistant lecturer on mechanics and experimental physics; 1873: associate professor; 1877: director of the Jena Observatory meteorological and astronomy departments.[2]

References

  1. ^ a b c d Blasius 1953, pp. 2–3
  2. ^ a b c d e f g h i j k l Debus et al. 1968, p. 2
  3. ^ a b Günther 1970, p. 6
  4. ^ a b c d e Günther 1970, p. 7
  5. ^ a b c d e Hoiberg 2010, p. 11
  6. ^ Joseph McCabe (1945). A Biographical Dictionary of Ancient, Medieval, and Modern Freethinkers. Haldeman-Julius Publications. Retrieved 7 April 2013. He was not only a distinguished German physicist and one of the most famous inventors on the staff at the Zeiss optical works at Jena but a notable social reformer, By a generous scheme of profit-sharing he virtually handed over the great Zeiss enterprise to the workers. Abbe was an intimate friend of Haeckel and shared his atheism (or Monism). Leonard Abbot says in his life of Ferrer that Abbe had "just the same ideas and aims as Ferrer."
  7. ^ Abbe 1874
  8. ^ a b c d e Pfeiffer 1991, p. 445
  9. ^ Joint Committee of Civil Engineers, American Congress on Surveying and Mapping & American Society for Photogrammetry and Remote Sensing 1994
  10. ^ a b Abbe 1881
  11. ^ Helmholtz & Fripp 1876
  12. ^ Abbe 1876
  13. ^ Abbe 1883
  14. .
  15. ^ Günther 1970, p. 9
  16. ^ "Abbe". Gazetteer of Planetary Nomenclature. USGS Astrogeology Research Program.

Sources

Further reading

External links