The top image shows an owl on the left and an eye on the right. There are two red lines going from the back of the owl into the eye, crossing as it reaches the back of the eye to show nearsightedness.

• Nearsightedness causes distant objects to seem blurry, while nearby objects appear clear.
• The eyeball is either too long or the cornea is curved.
• The image of the owl forms before reaching the retina. The bottom image shows an owl on the left and an eye on the right. There are two red lines going from the back of the owl into the eye, forming a V as it reaches the back of the eye. A concave lens is placed just before the red lines enter the eye to show how nearsightedness can be corrected.
• The concave lens spreads the light rays out before they enter the eye.
• The image of the now owls passes throught the concave lens, forming on the retina, instead of in front of it.