| 摘要 |
<p>The falsification of the identity card by copying or by chemical alteration of the original is rendered extremely difficult by a system of layers. The documentation, typically in the form of a photograph and text are registered photographically on a photosensitive layer. - Before exposure a motif (6) or pattern is superimposed and printed in transparent colour. When the card is exposed a mask corresponding to the pattern leaves an unexposed pattern in its shadow. Any attempt to replace the exposed image by a forged replacement would involve the removal of the top layer (b) thus exposing the photosensitive layer beneath. The pattern would thus disappear and would be extremely difficult to duplicate on the forged photo.</p> |
