Described herein is a contact lens which can actively generate oxygen that is directly supplied to the cornea when it is worn by a patient. The contact lens comprises: a lens body composed of a hydrogel material or preferably a silicone hydrogel material; at least one anode for electrolytically generating oxygen from water in contact with the anode; and at least one cathode operatively coupled with the anode to form an electrolytic cell. The anode and the cathode are embedded within the lens body and operatively connected to a power source and to a control element which automatically applies a potential voltage between the anode and the cathode, drives an electrical current through the anode and the cathode to generate oxygen from electrolysis of water, and controls the timing and duration of electrolysis of water in the eye.