The invention relates to a variable focus lens comprising an elastically deformable optical element (7) and a circumferential mechanism (10, 1, 5, 2, 3, 8, 21) to transfer a rotational movement to an axial movement, wherein by using a ball bearing system (9, 11, 12, 13, 15, 16, 17) the mechanism is optimized in a manner to reduce mechanical friction, friction variation and to improve force-direction dependent positioning insensitivity.