Draw two equal-length line segments parallel to each other, and then put arrows facing outward on the ends of one of the lines and arrows facing inward at the end of the other to make the Muller-Lyer Illusion. The line segment with the arrows pointing outward will appear to be bigger than the line segment with the arrow pointing inward, even though they are actually the same length.
Optical illusions are pictures that trick the eye into seeing something that isn't there. There are plenty of simple optical illusions that are easy to draw with a pen and paper.
- Blind spot test
- Titchener Illusion
Draw a large X on the right side of a piece of paper, and draw a small filled-in circle a couple inches to the left of the X. Close the right eye and stare at the X with the left eye. Start moving the sheet of paper closer and further away from the face. At some point, the circle will disappear which will indicate to the viewer where the blind spot is in the left eye.
Draw two equal-sized circles on a piece of paper. Draw a series of larger circles around the outside of one of the circles, and a series of smaller circles around the outside of the other. Even though the two center circles are equal in size, the circle with the smaller circles around it appears to be bigger than the circle with the larger circles around it.