LENSES CONVEX LENSES • Convex lenses cause light rays to converge • The focal point is the place where all of these rays converge, and the focal length is the distance this is from the centre of the lens • Convex lenses are used in magnifying glasses, cameras, microscopes and eyeglasses CONCAVE LENSES • Concave lenses cause light rays to diverge or spread • The focus is on the other side of the lens, at the pint where the divergent rays appear to have come from – it is a virtual focus • Concave lenses are used for short-sightedness, torches, telescopes and binoculars