| 摘要 |
A security device is presented, including: an array of focusing elements, each focusing element being adapted to focus light in at least two orthogonal directions, the focusing elements being arranged on a regular two-dimensional grid; and an array of elongate image elements overlapping the array of focusing elements, configured such that each focusing element can direct light from any one of a respective set of at least two elongate image elements to the viewer, in dependence on the viewing angle. In a first region of the security device, the elongate image elements extend along a first direction, and in a second region of the security device, the elongate image elements extend along a second direction which is different to the first direction. |
