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.

用微缩文字，来增加防伪特征。闪烁的微缩文字，没有用放大镜的情况下，看到的只是一条线，而用放大镜观看时，可以看到连续重复的文字、编码及数字等。