| 摘要 |
<p>A prescription sheet, made e.g. from paper suitable for laser printing, incorporates a sign, word or message which allows its authenticity to be verified by the pharmacist. The sign or message is invisible in normal circumstances, and is revealed e.g. by rubbing a specific area, enclosed by a frame (2), with a metal object. The message can be, for example, the words 'original document'. The sheet can also incorporate a symbol (3) printed in a colour which is difficult to photocopy.</p> |
