The invention relates to an optical electrowetting device comprising a conductive fluid (5; 101) and a non-conductive fluid (4; 102), said fluids being non miscible, and an insulating substrate (2; 103) on which both fluids are in contact and form a triple interface, wherein the natural contact angle (105) of the non-conductive fluid (102) on the substrate (103) in presence of the conductive fluid (101) is comprised between 0° and about 20°. This device may be a variable focus liquid lens, an optical diaphragm, an optical zoom. The invention further relates to an apparatus such as a camera, a cell phone, an endoscope or a dental video camera, comprising said electrowetting device and a driver or electronic means for controlling the lens.