Necker Cube: A Visual Illusion

When you stare at the wire frame model of a cube for a while, the cube seems to flip its orientation between two possible interpretations of the picture.

This applet requires Sun's Java VM 2 which your browser may perceive as a popup. Which it is not. If you want to see the applet work, visit Sun's website at http://www.java.com/en/download/index.jsp, download and install Java VM and enjoy the applet.

Buy this applet
What if applet does not run?

Discovered in 1832 by the Swiss chrystallographer L. A. Necker, this ambiguous picture now bears his name. The wireframe cube depicted in the orthographic projection, loses perspective clues that would otherwise help brain identify cube's orientation. This one is similar to the Staircase illusion and the Shifting Cube illusion.

49551824