Arthur König (1856–1901) was a student of Helmholtz who studied human color vision and color blindness. He proposed that dichromacy , the most common form of color blindness, was from the absence of one of the three "fundamental sensations" (now known as cone photopigments). By asking observers to match colors with a color-mixing device, König and Dieterici (1886) accurately inferred the spectral sensitivities of the three cone photopigments. König (1894) also demonstated the similarity of scotopic spectral sensitivity (the sensitivity of the rods) to the radiometrically measured absorption spectrum of the rod photopigment, rhodopsin.

This brief article was based on Pokorny (2004).

References

König A. (1894). Uber den menschlichen Sehpurpur und seine Bedeutung fur das Sehen. Sitz Akad Wiss Berlin, 577-598.

König, A., & Dieterici, C. (1886 ). Die Grundempfindungen und ihre Intensitats-Vertheilung im Spectrum. Sitz Akad Wiss Berlin, 2, 805-829.

Pokorny, J. (2004). The evolution of knowledge: Trichromacy as theory and in nature. Clinical and Experimental Optometry, 87, 203-205.