| 摘要 |
A method is disclosed for manufacturing a security feature on a security article. The security article includes a first layer of plastics material, and the method includes, in any order: using a laser to irradiate a first region of the security article, the laser being operated at a low power level and low speed; and using a laser to irradiate a second region of the security article, the second region at least partially overlapping the first, the laser being operated at a higher power level and higher speed. In this way, the overlapping portions of the regions are marked and exhibit an optically variable appearance. Also disclosed is a security article including a first layer of plastics material exhibiting a laser marking of which at least a portion has an optically variable appearance. |
