The Hollow Mask Illusion 

This exhibit shows a model of a hollow painted mask. But which side is which? With this illusion it is hard to tell.

Drag slowly across the image to rotate the mask, or use the square slider located near the bottom of the image.

When the mask is facing directly towards you it is not easy to assume that this is the back of the mask; or the front. The features of the hollow mask are ambiguous when they face towards you, or away from you.

Java Applet: ©2001 Tony Azevedo