The Convex Lens
The most commonly-seen type of lens is the convex lens. This type of lens is often used for close examination of small objects, such as rare stamps or coins. Children often use such a lens to concentrate sunlight to burn small pinholes in pieces of paper. That result by itself shows the power of concentrated light from the sun. But there must be more to it than that. Let's see if we can define the behavior of lenses a bit more specifically.