A zoom lens comprising, from the object side to the image side, a front lens group (72), a controllable lens group, and a rear lens group (74), the controllable lens group comprising a voltage-controlled electrowetting device, which device contains a first fluid (A) and a second fluid (B) having different refractive indices, with at least two first fluid-second fluid interfaces (40,42). The curvatures, and thus the lens power, of these interfaces can be changed independently by supplying a voltage (V1, V2) to electrodes (22,32) of the device, so that no mechanical movement of lens elements is needed.