New innovation helps single-pass inkjet presses achieve high quality at high speed 

Duesseldorf - Single-pass inkjet presses can now achieve significantly better print quality, thanks to a technology breakthrough to be unveiled by Global Graphics Software at drupa (drupa innovation parc 70B21\C20). Global Graphics Software is a leading developer of software platforms for digital printing, including the Harlequin RIP®.

The Harlequin Multi-Level Digital Screening Engine™ varies the amount of ink delivered from the inkjet head in any one location on any type of media to overcome common problems such as streaking and mottling that are frustrating many press manufacturers.

Martin Bailey, chief technology officer at Global Graphics Software, says: ”These advances in quality follow our extensive research with inkjet press manufacturers. Our new Harlequin Multi-Level Digital Screening Engine™ compensates for the quality problems currently faced by inkjet press manufacturers and helps them to achieve their goals of high quality and high speed. This new engine can be integrated into Digital Front Ends based on Harlequin RIPs, but will also work with third party DFEs by the addition of a standalone version to replace the native screening.” 

The Harlequin Multi-Level Digital Screening Engine™ is part of a new service Global Graphics will introduce to inkjet developers at drupa, that sees technicians measure test prints from single-pass greyscale presses, and process the results through Global Graphics’ new Digital Print Quality Optimizer tool. This calculates optimized patterning and overlaps for the various ink drop sizes available, to overcome common high speed inkjet press problems such as streaking and mottling.

The Digital Print Quality Optimizer calculates the optimum drop sizes and screen pattern for particular combinations of press, greyscale/multi-level print heads, and substrate. This significantly improves the printed quality of photographs and similar image types, especially in highlights and areas of subtly changing tones. Global Graphics measures the printing characteristics of the press and calculates optimal changes in the dot patterning. These mitigate the effect of drops straying in flight from their aim points and possibly then spreading and coalescing on the substrate before they can be cured. 

The Digital Print Quality Optimizer allows the Harlequin Multi-Level Digital Screen to be fine-tuned for particular press/substrate combinations, with particular regard to controlling the overlap between different drop sizes as they are used to build up tones from light to dark.

Global Graphics has published a White Paper that addresses the quality challenges associated with high speed greyscale presses and explains how the new Harlequin Multi-Level Digital Screening works to mitigate the quality variables. This White Paper, “Halftone screen Optimization for Single-Pass Inkjets,” can be downloaded from the Global Graphics website at www.globalgraphics.com/screening-optimizer-white-paper