Arthur König
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Arthur Peter König (1856 – 1901) is a German physicist specialized in optics. In 1886, he published an empirical determination of the spectral sensitivity of the human rod and cone sensors with Conrad Dietrici.
Biography
Born with congenital kyphosis, he devoted his short life to physiological optics. he studied in Bonn and Heidelberg, later moved to Berlin in the fall of 1879 where he studied under Hermann von Helmholtz, whose assistant he became in 1882. After obtaining a doctoral degree in 1882, he qualified for a professorial position in 1884. In 1890, he became director of the physical department of the Physiological Institute of the University of Berlin. In the same year he married Laura Köttgen with whom he had a son, Arthur, who became an astronomer. Circulatory problems caused by his kyphosis resulted in his premature death in 1901.<ref name="id1">Source of biographical information: M. Richter, Arthur König zum Gedächtnis, Die Farbe 5 (1956) No.1/2, 1–6.</ref>
Career
Originally working in physics, he began in 1883 to concentrate on physiological optics where he published over thirty papers, some of seminal importance. Among these are the 1886 paper (together with Conrad Dietrici) Fundamental sensations and their sensitivity in the spectrum, an empirical determination of what in fact is the spectral sensitivity of the human rod and cone sensors of vision.<ref name='id2'>A. König, Die Grundempfindungen und ihre Intensitäts-Vertheilung im Spectrum, Sitzungsberichte der Akademie der Wissenschaften zu Berlin, 29 July 1886, 805–829.</ref>
Earlier attempts at such measurements, but based on much simpler technology, had been made in 1860 by the English physicist James Clerk Maxwell (1831–1879). Using newly developed spectrophotometric equipment and modifications of the experimental procedure König and Dieterici published a more detailed paper in 1892, determining the "fundamental sensations" not only of subjects with normal color vision (trichromats) but also of dichromats and monochromats.<ref name='id3'>A. König, Die Grundempfindungen in normalen und anomalen Farbsystemen und ihre Intensitätsvertheilung im Spectrum, Zeitschrift für Psychologie und Physiologie der Sinnesorgane 4 (1892) 241–347.</ref>
With these measurements König provided evidence for the conjecture that the most common form of color blindness, dichromacy, is due to the absence of one cone type in the eye. Averaged König functions were widely used in psychophysical color stimulus calculations until new data based on a slightly different method were determined by John Guild and William David Wright in 1920s, resulting in the recommendations of standard observer data by the International Commission on Illumination (CIE, German:Commission Internationale de l'Eclairage) in 1931.
Other important investigations involve the sensitivity of the normal eye for differences in wavelength of light,<ref>A. König, Ueber die Empfindlichkeit des normalen Auges für Wellenlängen-unterschiede des Lichtes, Annalen der Physik und Chemie 22 (1884) 579–589.</ref> dependence of the Newton/Grassmann laws of color mixture on light intensity,<ref>A. König, Ueber Newton's Gesetz der Farbenmischungen, Sitzungsberichte der Akademie der Wissenschaften zu Berlin 31 March, 1887, 311–317.</ref> validity of Fechner's law at different light intensities,<ref>A. König, Experimentelle Untersuchungen über die psycho-physische Fundamentalformel in Bezug auf den Gesichtssinn, Sitzungsberichte der Akademie der Wissenschaften 26 July, 1888, 917–931.</ref> brightness of spectral hues at different light intensities, <ref>A. König, Ueber den Helligkeitswert der Spectralfarben bei verschiedener absoluter Intensität, Beiträge zur Psychologie und Physiologie der Sinnesorgane, 1891, 309–388.</ref> and the similarity between the perceptual sensitivity of the rod cells and the absorption spectrum of the rod photopigment, rhodopsin.<ref>A. König, Ueber den menschlichen Sehpurpur und seine Bedeutung für das Sehen, Sitzungsberichte der Akademie der Wissenschaften zu Berlin, 21 June 1894, 577–598.</ref>
König was an active editor. In 1889 he became the sole editor of Verhandlungen der Deutschen Physikalischen Gesellschaft. From 1891 on, together with the psychologist H. Ebbinghaus, he edited the journal Zeitschrift für Psychologie und Physiologie der Sinnesorgane. After Helmholtz's death in 1894, König took on the task of completing preparations for the second edition of the former's Treatise on physiological optics (1896, German:Handbuch der physiologischen Optik)<ref>H. von Helmholtz, Handbuch der physiologischen Optik, 2nd ed., Hamburg: Voss, 1896. </ref> to which he added a bibliography of vision consisting of nearly 8,000 titles.
König's 32 papers on physiological optics were published posthumously in book form in 1903.<ref>A. König, Gesammelte Abhandlungen zur physiologischen Optik, Leipzig: Barth, 1903.</ref>
Publications
- Vorlesungen Über Die Mathematischen Principien Der Akustik (1898)<ref>Template:Cite book</ref>
- Beiträge zur Psychologie und Physiologie der Sinnesorgane (1891)<ref>Template:Cite book</ref>
- Gesammelte Abhandlungen zur physiologischen Optik (1903)<ref>Template:Cite book</ref>
- Einleitung zu den Vorlesungen über theoretische Physik (1903)<ref>Template:Cite book</ref>
- Vorlesungen über theoretische Physik (1967)<ref>Template:Cite book</ref>