Streaming print data directly to printhead electronics
Sending print data directIy to the printhead electronics makes it possible to achieve blistering speeds even with variable data when every item is different. Can you maintain optimum quality too? The benefit is significantly improved productivity because you can keep presses running with no waiting time. At TheIJC, Düsseldorf, October 2019, Tom Mooney discusses recent technical breakthroughs and describes how the answer lies in a software engine that can obtain blistering speeds by driving data directly to the electronics whilst correcting for common quality defects.
Mottling is most common on less absorbent
substrates, often caused during drying/curing
Streaking is most common on more absorbent substrates,
caused by ink drops coalescing on the substrate surface
Solving the problems
▪ Vendors should make reasonable
efforts to tune inks, wave forms,
▪ After that software is usually the
fastest and most effective solution
▪ Micro effects
• Advanced Inkjet Screens
▪ All for both single-pass and
scanning head printers
▪ Variation within a head
• Commonly a ‘smile’ shape
• Caused by pressure or voltage changes
▪ Variation between heads
• Especially as heads become field replaceable
▪ Head wear
RIP and Screen “Direct” to the Device
• Printing variable data jobs where every page or item is different is here now.
• Inkjet is becoming an industrial process in a production workflow.
• Variable data is no longer just barcodes or text regions, it can encompass the whole print
• Key to success is 24/7 uptime and running at full speed maximising return on investment.
• Resolutions of devices, print heads and bars are rising (e.g. 600dpi to 1200 dpi,
quadrupling raster data).
• Devices are wider and faster (up to 4 metres wide and over 300 m/min).
• RIPing and screening offline to disk and then sending them to the
press is becoming a performance and storage capacity bottle neck.
• The solution is to RIP and Screen direct to the device.
RIPing “Direct” to the device
• PDFs can vary greatly in complexity if uncontrolled.
• The RIP becomes a critical component running the device and not a pre-press
• It can be hard to know what hardware to choose to achieve the rated speed of
the device without increasing impractically the bill of materials cost.
• Achieving all of this on current PC hardware at the device speeds, resolutions,
widths, etc. requires integrated innovation between multiple components.
• Having flexibility to choose the right hardware (head and driver board) for the job
can be key to introducing digital inkjet technology to a new market.
Direct Architecture (Harlequin and ScreenPro)
Farm RIP ScreenPro
Mako Streamline Direct
▪ Pre-Process designed to produce PDFs
• that are fast to RIP
• without any loss of quality.
• Deterministic (predictable RIPing speed)
• Mark objects that can be cached by Harlequin Direct
• OptimiseVariable Data Jobs
• Fix poorly constructed PDFs
• Down-sample large images
• Flatten complex transparency
• Convert to device colour-space
▪ Support other PDLs
• RIPs PDFs directly to hardware at device speed
(including screening and colour management)
• Sample front end that displays metrics and allows it to
be tested prior to integration into a PDF workflow
• PDF workflow agnostic
• Integrated into our Fundamentals PDF workflow
• Windows and Linux (Reduce bill of materials)
• Head driver electronics agnostic
• PrintFlat ready
• Takes contone rasters (e.g.TIFF) from a RIP and
halftone screen directly to the hardware (driver
electronics and print heads) at device speed.
• RIP and workflow agnostic
• Head driver electronics agnostic
• PrintFlat ready.
• Windows and Linux (reducing BOM).
• An ideal stepping stone to ripping directly:
• Inherently deterministic as the content of the
contone raster doesn’t vary the processing time
• Can be considered when changing the RIP would
be too disruptive to the customer or workflow