In accordance with the disclosure there is provided a thin circular lens body (10) formed of a single piece of plastics material. The body has a symmetrical curved rear surface (21) adapted to fit centrally on the corneal surface of the eye. The lens body has a mear-power correction region (31) of circular periphery in the central portion thereof, surrounded by a concentric distance-power annular correction region (41). The near-power central region has an area which is substantially equal to half the pupil area of the eye under average reading light conditions (about 80 foot-candles).