The present disclosure concerns a curvature-changing, accommodative intraocular lens (IOL) that may be implanted in the capsular bag of a patient's eye and is configured to harness the energy of the movement of the capsular bag upon contraction and relaxation of the ciliary muscles. In certain embodiments, the IOL includes a fluid optic body defining a cavity for containing an optical fluid, the cavity at least partially defined by a first optical membrane configured to extend across an optical axis of the patient's eye. The IOL further includes a plurality of lever arms extending from the optic body and configured to be in contact with the capsular bag such that axial compression of the capsular bag causes each of the plurality of lever arms to rotate about a corresponding pivot so as to modify a curvature of the first optical membrane.