Illusory contour optical illusion grid T-Shirt

It looks like there are bright white circles overlapping a grid, but it's just an optical illusion, in reality, it's just crossed lines. This illusion is sometimes mistakenly referred to as "Ehrenstein", but it is one of the illusory contour figure illusions. The ends of the dark segments produce the illusion of circles. The apparent figures have the same colour as the background, but appear brighter. A similar effect is obtained in the Kanizsa triangle (look for this design in our "Optical Illusions" collection). Instead of black lines, you may change the colour to anyone you like; play around to find what best matches the background (fabric) colour of your choice.