| 摘要 |
<p>A security device comprising a substrate (1) formed with a surface relief (2) defining an optically variable effect generating structure. At least two different reflection enhancing materials (4, 6) are provided on, or on the same side of the substrate (1) with respect to the surface relief (2), whereby the optically variable effect can be viewed against a background defined by the reflection enhancing materials.</p> |
