| 摘要 |
<p>The invention refers to a photosensitive device with typical appearance similar to a post office stamp, provided with information and equipped with at least two internal layers, able to perform the information transfer, be it coded or not, from one layer to another, activated by an appropriate light stimulus. Furthermore, the invention refers to an information coding process, which the result is an image whose features (shape, intensity, etc.) are useful when associated to the occurrence of an event and its duration, e.g. proof of the broadcasting of a specific television program within a given time period.</p> |
