Benham's Wheel

An optical top marked in black with the pattern shown above. When the wheel is spun (especially slowly), the black broken lines appear as green, blue, and red colored bands!

References

Cohen, J. and Gordon, D. A. ``The Prevost-Fechner-Benham Subjective Colors.'' Psycholog. Bull. 46, 97-136, 1949.

Festinger, L.; Allyn, M. R.; and White, C. W. ``The Perception of Color with Achromatic Stimulation.'' Vision Res. 11, 591-612, 1971.

Fineman, M. The Nature of Visual Illusion. New York: Dover, pp. 148-151, 1996.

Trolland, T. L. ``The Enigma of Color Vision.'' Amer. J. Physiology 2, 23-48, 1921.

• Palindromic Number
• Palindromic Number Conjecture
• Pancake Cutting
• Pancake Theorem
• Pandiagonal Square
• Pandigital
• Panmagic Square
• Pantograph
• Papal Cross
• Pappus Chain
• Pappus-Guldinus Theorem
• Pappus's Centroid Theorem
• Pappus's Harmonic Theorem
• Pappus's Hexagon Theorem
• Pappus's Theorem
• Parabiaugmented Dodecahedron
• Parabiaugmented Hexagonal Prism
• Parabiaugmented Truncated Dodecahedron
• Parabidiminished Rhombicosidodecahedron
• Parabigyrate Rhombicosidodecahedron
• Parabola
• Parabola Caustic
• Parabola Evolute
• Parabola Inverse Curve
• Parabola Involute