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Gateway to Spectroscopy > Physical Background > History of Spectroscopy > Early 19th century

Early 19th century

  • 1801 - J W Ritter and W H Wollaston discovered Ultraviolet, by its chemical effects.
  • 1801 - Thomas Young presented the principle of the interference of light.

[Fraunhofer lines]

In 1802, William Hyde Wollaston fitted the entrance of his spectroscope with a fine slit to improve resolution and discovered the presence of fixed black lines within the solar spectrum.
     In 1814, Joseph von Fraunhofer invented the diffraction grating (transmission). After fitting it onto a theodolite, he resumed Wollaston's work and marked the relative positions of several hundreds of black lines. He was, however, unable to provide a satisfactory explanation for their presence.

  • 1807 - Young presented the three colour theory of vision.
  • 1811 - Arago discovered rotary polarization by quartz.
  • 1813 - Arago discovered the polarization of scattered light.
  • 1815 - Fresnel rediscovered the interference of light.
  • 1818 - Fresnel explained the polarisation of light.
  • 1826 - Balard discovered the photo-sensitivity of silver bromide.
  • 1826 - Talbot and Herschel studied the changing colours of flames when sodium, potassium, lithium and strontium salts were introduced into the flame.

Authors: Jean Charles Lefebvre, Jobin-Yvon Emission and Richard Payling, Surface Analytical
First published on the web: 15 December 1999.