Encyclopedia of Color Science and Technology

2016 Edition
| Editors: Ming Ronnier Luo

Purkyně, Jan Evangelista

Reference work entry
DOI: https://doi.org/10.1007/978-1-4419-8071-7_342

Biography

Jan Evangelista Purkyně (Fig. 1) was born sometime between 17 December and 19 December 1787 in the castle in Libochovice near Litomeřice, Bohemia (then part of the Austrian monarchy) and now Czech Republic [1]. Purkyně died on 28 July 1869.
Purkyně, Jan Evangelista, Fig. 1

Purkyně, Jan Evangelista (1787–1869)

He was the oldest son of Josef and Rozálie (born Šafránková) Purkyně. His father worked as the chamberlain of Libochovice manor. Jan learned to observe nature and people initially from his father, who used to take him on business trips. He inherited diligence and discipline and also a sense of humor from his mother. Jan began to read early and was introduced to Komensky’s publication Orbis Pictus. He also learned to read Latin and Greek texts from a priest called Schiffner in Libochovice.

In 1793, Purkyně’s father died and Rozálie was left with her two sons Jan and Josef. With assistance from Rozálie’s friends, Jan was enrolled at the Piarist Grammar school. After graduation from the grammar school (1804) and upon recommendation of his teachers, Jan went to a monastic house in Dobrá Voda. Due to his excellent performance, he managed to complete the 3-year program in 1 year. He then started to teach at the lower grammar school in Strážnice, and from there, he went to teach at the Piaristic Institute in Litomyšl. There, he devoted himself to the study of philosophy and history and poetry and became a devoted fan of the classical German philosopher F. W. Schelling.

In 1807, Jan returned home, but in the fall of the same year, he started to study philosophy in Prague University. He had to leave his studies after the third year because of financial reasons and accept to teach Baron Hildprandt’s son Ferdinand in Blatná. With Hildprandt’s financial support, Jan went back to Prague in 1812 to study medicine.

Upon completion of his medical program, he unsuccessfully applied to several faculty positions including professor of pharmacology in Prague, professor of anatomy and physiology in Graz, and professor of anatomy in Ljubljana.

In 1822, he secretly traveled to Germany and was introduced to Schultz and subsequently met with Goethe. In 1823, and upon the recommendation of Goethe, the Prussian king signed a decree which nominated Purkyně a professor in Physician School of Wroclaw (Breslau in Prussia) where he continued his research. There he lectured physiology, eye pathology, and psychology, but his lectures were not well attended. He continued his study of subjective visual perception and published a comprehensive work on this topic which was dedicated to Goethe. In 1826, he was accepted as a Masonic Trainee in Berlin, 1 year later as Journeyman and subsequently as Master. In 1825, he published his work “Neue Beitrage zur Kenntnis des Sehens in Subjektiver Hinsicht” (Reimer, Berlin, pp. 109–110), which earned him the eponymy Purkinje effect (or Purkinje shift) [2].

In 1827, Jan Evangelista Purkyně (a protestant) got married to Julie Anežka Rudolphi (a catholic) in Berlin, and they kept their respective denominations. With Julie, he had two daughters and two sons. Both of his daughters died of cholera. Purkyně became a member of the Leopoldine science academy in 1829. In 1830, he became a professor of botany at Wroclaw University. In 1834, his wife died, leaving Purkyně with two young sons. He did not remarry.

Purkyně turned his focus to botany and was awarded the Montyon Prize in France for his monograph “De cellulis antherarum fibrosis nec non de granorum pollinarium formis” in 1833. In 1836, the State Secretary accepted Purkyně’s suggestion for the establishment of a physiological institute (the first in Central Europe). In 1849, Purkyně was called back to Prague as a professor by the emperors’ decree. Purkyně was later nominated as a member of London’s King Society. Purkyně was also honored as the guardian of Matice česká – a committee for edification of language and literature from 1852 to 1858. Thanks to Purkyně, the first Czech industry school (1857) was also opened in Prague where he became the principal from 1857 to 1859. His house was also a place where many Czech artists met and discussed work.

Major Accomplishments/Contributions

Subjective Visual Phenomena (1818–1825)

Jan Purkyně was one of the best known anatomists and physiologists of his time. He was probably one of the early pioneers of what we now call vision science. As a medic, Purkyně studied differences in subjective visual phenomena including lightshade, galvanic and vassal patterns (embranchment of vassals in his own eye), glare patterns, subjective feelings in darkness (phosphenes), blind spot, unity of both eyes’ visual fields, double sight, indirect sight, colorblindness in peripheral retina, light patterns, and afterimages. Probably, one of the most well-known contributions of Purkyně to color and vision science is that which bears his name, the Purkyně effect.

As a medical student during spring walks through the flowering countryside, Jan observed that after the sunset, the color of flowers appeared to change; red blossoms appeared darker, yellows faded, and the blues seemed brighter. Purkyně studied this phenomenon systematically and found out the same results with other object colors. That is, under decreased illumination, blue colors appeared lighter than reds. He focused his studies on this topic, and in 1818, he defended his dissertation in the faculty of medicine on “Contributions to the knowledge of sight from a subjective sense” [3]. The effect is shown in the picture of blue and red flowers simulated under three illumination conditions: average (when cones are active), dim (when rods intrude), and dark (when cones become mostly deactivated). This phenomenon is due to the contribution of rods on the perceived color of the scene. Rods require low levels of illumination to become activated (and are associated with night vision), whereas cones are activated at much higher levels of illumination (and are associated with day and color vision). Under certain conditions, e.g., during dawn or dusk, there is just sufficient illumination to activate cones, but illumination is low enough to activate rods also. If the contribution of rod signals to the overall image and thus the perceived color exceeds about 10 %, the effect becomes known as rod intrusion. Since rods’ peak sensitivity is around 496 nm, which is much closer to the peak sensitivity of the short-wavelength-sensitive cones (responsible for blue colors at 419 nm) compared to that of long-wavelength-sensitive cones (responsible for red colors at 558 nm), the overall perception of the observed scene is shifted toward blue at low levels of illumination when rods become activated. Therefore, blue colors appear brighter, whereas red colors appear very dull and almost black (Fig. 2).
Purkyně, Jan Evangelista, Fig. 2

Observing red and blue flowers under average (left), dim (middle), and dark (right) illumination conditions. The simulation shows that under low levels of illumination levels, the blue colors appear much brighter compared to red ones

Objective Eye Examination Techniques (1823)

Purkyně recommended a technique for systematic objective examination of eyes using reflective pictures. In this process, candle flame mirrors on the front and back of the cornea and then on the front and back of the retina. Purkyně examined the possibility of using reflective pictures to measure the curvature of cornea (which became the principle of keratometry and ophthalmometry) and its use in diagnosis of eye diseases and defects [4]. After many years, Purkyně obtained an achromatic Plossl microscope, which he placed in his own apartment since he did not have a suitable place within the university. He was deeply interested in the stomach’s mucosa structure and discovered stomach glandule. He also observed eye luminescence and the possibility of observing eyes’ background in vivo, a principle of ophthalmometry which was later established by Helmholtz in 1850 [5].

References

  1. 1.
    Bhattacharyya, K.B.: Eminent Neuroscientists: Their Lives and Works, p. 182. Bimal Kuman Dhur of Academic Publishers, Kolkata (2011)Google Scholar
  2. 2.
    J. Purkinje: Neue Beiträge zur Kenntniss des Sehens in subjectiver Hinsicht [Observations and Experiments on the Physiology of the Senses: New Contributions to the Knowledge of Vision in Its Subjective Aspect] 2 vols., 192 pp. Georg Reimer, Berlin (1825) (in German)Google Scholar
  3. 3.
    Purkinje, J.: Beobachtungen und Versuche zur Physiologie der Sinne. Erstes Bändchen, Beiträge zur Kenntniss des Sehens in subjectiver Hinsicht. Doctoral thesis (1819) (in German)Google Scholar
  4. 4.
    Purkinje, J.: Commentatio de examine physiologico organi visus et systematis cutanei [Contributions to physiological research of sight and skin system]. Doctoral thesis, University of Wrocław, Wrocław (1823) (in Latin)Google Scholar
  5. 5.
    Wade, N.J., Brožek, J.: Purkinje’s Vision: The Dawning of Neuroscience. Lawrence Erlbaum Associates, Mahwah (2001)Google Scholar

Copyright information

© Springer Science+Business Media New York 2016

Authors and Affiliations

  1. 1.Faculty of Textile Engineering, Laboratory Color and Appearance MeasurementTechnical University of LiberecLiberecCzech Republic
  2. 2.Color Science and Imaging Laboratory, College of TextilesNorth Carolina State UniversityRaleighUSA