The Munker-White Illusion is an optical illusion that was discovered in the 1950s by German psychologist Hans Munker. It is a type of ambiguous figure, which means that it can be seen in two different ways. The illusion is composed of two overlapping circles, one black and one white
From Wikipedia
White's illusion is a brightness illusion in which certain stripes of a black-and-white grating are replaced by gray rectangles of the same color, luminance, and opacity. The brightness of the gray rectangles appears to be closer to the brightness of the top and bottom bordering stripes. This is opposite to any explanation based on lateral inhibition; hence it cannot explain the illusion.