| 摘要 |
Valuable data carrier (1), e.g. a banknote, has a half-tone grid pattern image (2) that has been converted from a half-tone master illustration and comprises regularly spaced grid lines, the width of which is modulated to correspond to the tone value to be represented. Modulation of the width of the grid lines is on one side of the line only, so that one side is smooth and the other side is width-modulated. |
