By accident, I stumbled over this optical illusion:
It is not a strong one, and maybe you don't experience it, but I see the size of the circles in the second last row decrease from left to right. I don't see this in all the other rows.
Maybe it's only the illusion of an illusion, but in case it's a real illusion (which you experience, too) I wonder:
Does it belong to a class of optical illusions which already is quite well understood? If so: Under which name and where can I learn more about this class of optical illusions? If not so: Has anyone an idea how to explain it?
Note that the illusion may depend on the angle of view. I have the impression it does but did not investigate it systematically. I also may depend on the size of the image - on small displays it might not "work".