The outer drum-type photo typesetter for four-channel or multi-channel laser modulation anisotropism, in the image when film to some serious may form a moire hapalogenys forplanar.

• 边鼓型照排机其四路或众路激光调制不平衡的话，在成像时软片的图像局部不离不定酿成惨轻的歪条形龟纹。