| A | B |
|---|
| lens | transparent object with at least one curved surface |
| convex lens | lens that is thicker in the middle |
| concave lens | lens that is thicker at the edges |
| nearsighted | trouble seeing far away objects |
| farsighted | trouble seeing nearby objects |
| contact lenses | clear, thin lenses that are placed infrom of the cornea |
| refracting telescope | uses 2 lenses to refract light to make an image. |
| reflecting telescope | uses a concave mirror and a flat mirror to reflect image. |
