| S.N. | Convex lens | Concave lens |
| 1. | A lens which is thick (bulged) in the middle but thin (tapered) at the edges is called convex lens. | A lens which is thin in the middle but thick at the edges is called a concave lens. |
| 2. | It converges the parallel beam of light falling on it, hence also called a converging lens. | It diverges a parallel beam of light falling on it, hence also called a diverging lens. |
| 3. | It has a real focus. | It has a virtual focus. |
| 4. | The power of this lens is positive. | The power of this lens is negative. |
| 5. | It forms a real or virtual image depending on the position of the object. | It always forms a virtual image. |
| 6. | It is used in the correction of long-sightedness. | It is used in the correction of short-sightedness. |
| 7. |  |
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