| 摘要 |
A security device (10) having: a base (12) having a pattern (14) thereon; a mobile component (16) disposed in contact with the base (12), the mobile component (16) containing a plurality of reversibly adsorbable particles; and a cover (20) attached to the base (12) around the mobile component (16) to maintain the mobile component (16) in contact with the base; wherein the adsorbable particles are mobile and reversibly changeable between a first state where the adsorbable particles are adsorbed to at least a predetermined percentage of the pattern and a second state where the adsorbable particles are adsorbed to less than the predetermined percentage of the pattern. |
