Color Shift of Printing with Hybrid Halftone Images for Overlay Misalignment

Color printing proceeds with multiple halftone separations overlay. Because of separation overlay misalignment in printing, the percentage of different primary color combination may vary and it will result in color shift. In traditional printing procedure with AM halftone, every separation has different screening angle to make the superposition pattern in a random style, which will reduce the color shift. To evaluate the color shift of printing with hybrid halftoning, we simulate printing procedure with halftone images overlay and calculate the color difference between expected color and color in different overlay misalignment configurations. The color difference for hybrid halftone and AM halftone is very close. So the color shift for hybrid halftone is acceptable with current color printing procedure.

Authors:

• Xu Guoliang
• Tan Qingping

Keywords:

• color printing
• AM halftone
• Hybrid halftone
• misalignment
• color shift
• Neugebauer Color Equation

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