文字数字的

Flashing microtext that, when viewed with the unaided eye, appears to be part of the line design, bet under magnification is seen as a repeated pattern of words, codes or numbers.

通过使用缩文字，来增加防伪特征。闪缩文字，没有使用放大镜情况下，看到只是一条线，而使用放大镜观看时，可以看到连续重复文字、编码及数字。