This is one of my earliest color optical illusions. There is no yellow or green in the diamond shapes, just vertical black lines! (If you don’t believe it, use a eyedropper tool to check it.) This intriguing visual effect is mainly due to “color contrast induction“.
Below are the animated versions of my op art:
Some intriguing variants. The yellowish and greenish spirals within the radiating patterns are actually made of black segments.