Optical Illusions - Continued...

Muller-Lyer Illusion

Are the horizontal lines the same length? Yes, but they appear to unequal. The direction of the angles at the ends of each line creates the illusion.

Near and Far

Which is bigger ? Circle A or circle B? Actually, they are the same size. They appear different because of their positions within the angle.

Necker Cube

Which square is the front of this cube? It has an ambiguous perspective.

Neon-Color Spreading

What color is the circle in the center of these diagrams? In this optical illusion, when the red lines connect the black ones, the color flows out of the intersecting lines and appears to create a circle.

Open Sesame

Which end is closer to you? Look closely at this tube for a minute or so, and then decide if you are looking down the tube from the right or the left.

Poggendorf Illusion

Which line above the rectangle is the continuation of the line below the rectangle? When a shape interrupts a line, it can be difficult to tell where the line continues.

Ponzo Illusion

Which line is longer? When two horizontal rods of equal length are drawn over an upside down V, the upper rod appears longer than the lower rod. (See Corridor Illusion).

Schroder Staircase

Are the stairs rightside up or upside down?