Auto register adjustment using CCD cameras

[UK Printer]

Bit of a specific request this.

We need to find a company that can help us solve a manufacturing problem.

We are laying spot UV over the top of digitally printed sheets. We currently get in register by simple sidelay alignment, but need to develop a scanning system to read registration points on our printed sheets.

I guess we need to mount some CCD cameras before the sheets arrive at the Inkjet head array, to read the registration marks and compare these against the BITMAP file, i want the software to make compensations for image skew, changes in size etc, basically all the nasties associated with digital print :-)

I'm hoping someone can maybe point me in the direction of a company that could help us.

You help appreciated as always.

[gordo]

You might try contacting the people at Apollo Systems - click here: Apollo Systems, LLC

hope this helps.

best, gordo

[effeegee]

Most digital print has a primary axis for drift for which a variation on the side lay approach will work for the 'x' axis.
A printed line (in the trim area) scanned by a 'camera' and controlling an adjustable side lay is established technology. See Rollem Autolay animation ‪Rollem AutoLay - 2007.wmv‬‏ - YouTube.

This method needs time/distance to reach correct position and might involve extending the feed table. How such a solution might be integrated is a matter of engineering. Rather than detecting a sheet edge a second scanning control reading the beginning of the image on the sheet can be used to compensate for drift in the 'y' axis. Neither have any impact on operating speed.

A single scanning approach to control sheet position and compensate for skew (let alone size or other nasties) would probably be frighteningly slow and expensive.

[Cornishpastythighs]

try these guys as well
CC1 Inc.

[StuartJMurphy]

Thanks for the mention effeegee. We at Rollem have had an option on our equipment to correct image drift for a while now. We provide very accurate registration to the print with our AutoLay working at full sheet processing speed.

Here is a video with the system on business cards:

‪Rollem JetStream + AutoLay + Cassette Collection - Business Cards - 2008.wmv‬‏ - YouTube

Here a video of the Rollem AutoLay on playing cards:

‪Rollem Revolution + AutoLay - Playing Cards - 2008.wmv‬‏ - YouTube

Do get in touch if you want to discuss a registration system to add to your UV system.
www.rollem.com

Cheers,
Stuart

[UK Printer]

Appreciate the advice, droped stuart a line, we already have his Jetstream in use on site, very nifty machine too.

I'll give all of the companies mentioned a call, see if there is something that can be created to solve the problem.

We have a zund cutting table that does exactly what we need, instead of cutting though we want to lay down UV overprint.

Exact same process though, ICC camera picks up a bunch of circular register marks and this compared to the file on the computer lets the cutting tool know how much skew / shrinkage / growth and everything else has occurred.

The software for the zund is called i-CUT, i got in touch with them and they weren't interested in using their software for anything else than cutting, fair enough but a bit tantalising knowing the solution exists already, we just need to apply it to a new application.

If anyone has any flashes of inspiration i'm all ears however.

[effeegee]

Further to my earlier reply continuous printing systems have been using video inspection and line scan systems for ages to inspect and correct defects of many types and to create closed loop control systems for colour and register. Maybe this could prove a fruitful possibility - see below.

Although as you bring up in your recent post re Nexpress it is nit-picking at tolerances which are outside the scope of control. I don't immediately follow how a return on investment can be generated from solving this problem.

There's an element of 'I wouldn't start from here' when it comes to chasing skew and size. Can't old fashioned spreads and chokes take care of the problem at a pre-press level?

Nevertheless Lake Image Systems has technology which should be capable of using a line scan camera to measure print dimensions to derive co-ordinates (or similar) which when processed appropriately could scale the varnishing image. It does of course beg the question as to what the position tolerance is on the varnishing process after any scanning might have taken place. Try calling Pete Sirett at Lake http://www.lakeimage.com The economics involved in tailoring a system might be totally off-putting

Good luck - let me know where you go with this

Frank Elston