Abstract: The present invention provides an intra-ocular lens (IOL) whose focusing performance can be modified after its implantation in the eye without a need for any invasive procedure. An IOL of the invention has an optical chamber having at least a flexible region that is deformable under influence of a fluid. The IOL further include a reservoir for storing an optical fluid in fluid communication with the optical chamber, and a valve that regulates the fluid communication between the reservoir and the optical chamber. The lens can also include a pump that is actuated by an external energy source to transfer the optical fluid between the reservoir and the optical chamber to change the amount of fluid in the optical chamber, thereby modifying the focusing performance of the IOL.