双色半色调:一单色原稿造成双色效果。主要的半色调版印深色；另一色用平网，印浅色。有别于双色调。亦称假双色调。

• duplex half-tones: Two colour printing made from a monochrome original.The main half-tone are used to print a dark colour,while the other,being a flat tint are used to print a light colour.Not to be confused with a duotone.Also called Fake duotone.