Devices using lenses.

Such devices are found at every step and are, probably, in every home. A classic example is ordinary glasses, which are still in demand despite the popularity of contact lenses. Lenses are also used in other optical devices – microscopes, telescopes, video cameras and movie cameras, in projectors and binoculars. The simplest of optical instruments is an ordinary magnifying glass, which is also used at home: when looking at small objects, repairing, sewing, reading texts printed in small print.