dInside the eye there is a lens that can change its
fuedman
thickness. VWhen we look at a distant object, the lens
gets thinner. When an object is closer, the lens gets
thicker.' In this way, the light coming through the lens
always meets at the same point)at the back) of the eye.)
局り
(Figure 2-1)A nearsighted person's eye cannot change
he thickness of the lens very well. The light coming into
he eye meets before it reaches the back of the eye.
Figure 2-2) By using a concave lens, the light meets
arther back in the eye. (Figure 2-3)
