Halo effect: Build-up o fink at edges of printed letters and half-tone dots,creating a darker perimeter to the dot.A characteristic of relief printing (letterpress and flexo).

• 光晕效应:印刷字体和半色调网点的边缘积聚油墨，造成较黑周边的效果。是凸版印刷（活版 和胶版）的一个特征。