Optical Illusions
Can you believe your eyes? (1)
Can you believe your eyes?
Well, can you?
Which red circle is bigger?
The Lipps Illusion ~ 1897
Are the red lines curved?
Is that a square and a circle?
Are you certain you can see a spiral?
What about this one ? A spiral or concentric circles ? Sure ?
Are you seeing spots before the eyes yet? - The Hermann Grid
The intersection you look at won't change colour, but the others will !!
A variation of the Hermann Grid
How many black dots are there?
A variation of the Hermann Grid
What happens when you stare at the center of this image?
What about the stripes in the circles? Sure?
What is going on here?
Thiery's figure
The Zollner Illusion - The longer lines really are parallel!
How many triangles can you see in each of these 4 pictures
1, 2 or none?
If you see an upside-down triangle in these pictures, what happens to its shape in the bottom right picture?
Kanizsa figures