
The ellipse on the right appears to be longer and thinner than the one on the left, but it is in fact the same shape rotated 45 degrees.

The ellipse on the right appears to be longer and thinner than the one on the left, but it is in fact the same shape rotated 45 degrees.

There are twelve black dots in this classic illusion designed by Akiyoshi Kitaoka, but due to how our neurons are concentrated in the fovea, it’s difficult to see more than one at a time. Can you relax your mind enough to catch them all?
This optical illusion is driving the internet crazy! The Daily Mail reports that this “Seemingly simple optical illusion will have your brain doing somersaults.” Though it seems like there are more, there are in fact only five bars in this diagram.
![Which rectangle is darker? Though the one on the left appears to be darker, they are in fact exactly the same. Blocking the dividing line with your middle finger may help illustrate this devilish illusion. [h/t Boing Boing]](https://64.media.tumblr.com/b2bf8776921026c1f9e84972e22af5e3/tumblr_nzbp050DSr1r9nopqo1_400.jpg)
Which rectangle is darker? Though the one on the left appears to be darker, they are in fact exactly the same. Blocking the dividing line with your middle finger may help illustrate this devilish illusion. [h/t Boing Boing]
Which line is the largest?
Due to the structure of your eyes rods and cones (retina rods and cornea/Coriolis cones) and this pattern appears to be slowly rotating at the speed of the earth’s rotation. try looking at this one in south “of the border” America!

This hazardous pit is designed to resemble an ultra-realistic 3D chalk painting.

Pareidolia is a phenomenon whereby random visual stimuli, such as clouds, are psychologically interpreted as animals, faces, or other significant images. In this picture of random foliage, some people claim to see the head of Paula Deen.
According to urban legend, if you spin the Nazi Swastika fast enough, the logo of German national automaker Volkswagen will appear. Can you see it?

Let us consider two patterns made of parallel and equidistant lines, e.g., vertical lines. The step of the first pattern is p, the step of the second is p+δp, with 0<δ<1.
Can your eyeballs resist the sky blue “Moiré Effect”?

Though not strictly an optical illusion, the Isihara Color Blindness test illustrates the variability of human perception. The numeral “82” here is clearly visible to viewers with normal color vision.