Model based printer linearization

Abstract

We introduce two novel methods for accurately predicting the conversion function from digital input to printed dot area. This conversion function is substantial for dot gain compensation. Dot gain compensation (“press linearization”) is aimed at keeping the print color consistent while the press physical parameters drift. To achieve good and consistent print quality, this procedure should be done often. However, since it requires the printing of special jobs with color patches, it consumes both time and paper. This procedure is even more unwieldy in web presses that print on rolls of paper. The goal of this work is to achieve good print quality with much fewer print interruptions.The first method is based on a physical model and the second is built on a complete heuristic model. Both methods use the digital data and a small set of measurements as an input. These methods provide the possibility to accurately and directly predict the conversion function. We further discuss the concept of a full physically predictive method. The methods were tested on an HP-Indigo digital press but the concept is applicable to any printer.