Eyeglasses consist of two curved lenses that are mounted in a frame and positioned in front of the eyes. Contact lenses are thin, curved discs that are placed directly on the surface of the eye. Both forms of spectacle correction work by bending light rays as they enter the eye, helping to focus the light on the retina and produce a clearer, sharper image.Eyeglasses consist of two curved lenses that are mounted in a frame and positioned in front of the eyes. Contact lenses are thin, curved discs that are placed directly on the surface of the eye. Both forms of spectacle correction work by bending light rays as they enter the eye, helping to focus the light on the retina and produce a clearer, sharper image.