The illusion shown above which was discovered by Helmholtz in the 19th century. Despite the fact that the two above figures are identical in size, the white hole looks bigger than the black one in this illusion.
Irradiation Illusion
See also
IllusionExplore with Wolfram|Alpha
References
Pappas, T. "Irradiation Optical Illusion." The Joy of Mathematics. San Carlos, CA: Wide World Publ./Tetra, p. 199, 1989.Referenced on Wolfram|Alpha
Irradiation IllusionCite this as:
Weisstein, Eric W. "Irradiation Illusion." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/IrradiationIllusion.html