An eye-implantable electrowetting lens can be operated to control an overall optical power of an eye in which the device is implanted. A lens chamber of the electrowetting lens contains first and second fluids that are immiscible with each other and have different refractive indexes. By applying a voltage to electrodes of the lens, the optical power of the lens can be controlled by affecting the geometry of the interface between the fluids. When the electrowetting lens is inserted into the eye, the lens chamber may contain only one of the first and second fluids. The other fluid can be added after insertion through a needle, a tube, or some other means. Having only one of the first and second fluids in the lens chamber during insertion of the lens can prevent fouling of internal surfaces due to folding or other manipulation of the lens during the insertion process.
