Question

Why is orange the afterimage of blue

Answer 1

Negative afterimages, Negative afterimages are caused when the eye's photoreceptor, primarily known as rods and cones adapt to overpopulation and lose sensitivity.

Answer 2

After about ten seconds it is turned off, and viewers perceive a blue afterimage, blue being the complementary color to orange. In the second part, a spotlight projects a blue square of light onto a wall of a separate space. This time the afterimage is orange.