| 摘要 |
<p>Tagged microparticles are produced by affixing a substrate sheet to a support, cutting the substrate into a plurality of microparticles with a first laser and then marking each particle with the same or a second laser, before removing the particles from the support. The marking on each particle may be discernible by means of a contrast, colour or light reflectance or transmission. The substrate sheet may comprise a plastic foil with a metal layer deposited thereupon, with the markings being provided by evaporating portions of the metal layer. The support may be a glass sheet, with the substrate fixed thereto by a spray adhesive. This adhesive is then dissolved by a suitable solvent (with optional anti-oxidant additive) to remove the particles from the support.</p> |
