Magnifying glass, spectacles, telescope, microscope – all devices in which light refraction is put to good use. Because they all have lenses of glass that refract light in a special way: they make things appear larger than they really are – or in some cases smaller.

The fact that lenses are able to do this is due to their shape. A drop of water also functions like a magnifying lens. Its curved surface bends the light rays in such a way that they run together. A convex lens bundles parallel light rays at its focal point. Other lenses scatter light, making everything appear smaller. In optic devices the lenses are put together to create the desired effect.

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