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Fechner color effect

From Wikipedia, the free encyclopedia
A sample of a Benham's top (animated version)
Movie

The Fechner color effect is an illusion of color seen when looking at certain rapidly changing or moving black-and-white patterns. They are also called pattern induced flicker colors (PIFCs).

The effect is most commonly demonstrated with a device known as Benham's top (also called Benham's disk). When the top is spun, arcs of pale color are visible at different places on the disk that forms its upper surface. The effect can also be seen in stroboscopic lights when flashes are set at certain critical speeds. Rotating fan blades, particularly aluminum ones, can also demonstrate the effect; as the fan accelerates or decelerates, the colors appear, drift, change and disappear. The stable running speed of the fan does not (normally) produce colors, suggesting that it is not an interference effect with the frequency of the illumination flicker.

The effect was noted by Gustav Fechner and Hermann von Helmholtz and propagated to English-speakers through Charles Benham's invention of his top. Florence Winger Bagley was one of the early investigators of this phenomenon.[1]

The phenomenon originates from neural activity in the retina and spatial interactions in the primary visual cortex, which plays a role in encoding low-level image features, such as edges and spatiotemporal frequency components.[2] Research indicates that the blue–yellow opponent process accounts for all the different PIFCs.[3]

Research has been done into the use of Benham's top and other PIFCs as diagnostic tools for diseases of the eye and the visual track. It has shown particular promise in detecting optic neuritis.[4]

Benham's top

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Benham's top is named after the English newspaper-man, amateur scientist, and toymaker Charles Benham, who in 1895 sold a top painted with the pattern shown. Benham was inspired to propagate the Fechner color effect through his top after his correspondence with Gustav Theodor Fechner, who had observed and demonstrated the said effect. Benham's top made it possible for speakers of the English language to learn of the Fechner color effect, about which Fechner's original reports were written in German.[5]

See also

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References

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  1. Bagley, Florence Winger (1902). "An investigation of Fechner's colors". American Journal of Psychology. 14 (4): 488–525. doi:10.2307/1412440. JSTOR 1412440.
  2. von Campenhausen C.; Schramme J. (1995). "100 years of Benham's top in colour science". Perception. 24 (6): 695–717. doi:10.1068/p240695. PMID 7478909. S2CID 45743116.
  3. Schramme J. (1992). "Changes in pattern induced flicker colors are mediated by the blue/yellow opponent process". Vision Research. 32 (11): 2129–2134. doi:10.1016/0042-6989(92)90074-S. PMID 1304090. S2CID 27439228.
  4. Pilz J.; Marre E. (1993). "Pattern-induced flicker colors. An ophthalmologic examination method". Ophthalmologe (in German). 90 (2): 148–154. PMID 8490297.
  5. Krantz, John H. (2013), "Fechner's Colors and Behnam's Top", in Luo, Ronnier (ed.), Encyclopedia of Color Science and Technology, New York, NY: Springer New York, pp. 1–4, doi:10.1007/978-3-642-27851-8_65-2, ISBN 978-3-642-27851-8, retrieved 2026-05-06
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