Square Spot versus Gaussian laser technology

[danomo_mz]

From a purely technical view, putting a side views whether Kodak is a good company to deal with or not, what about laser imaging quality? Is a sharper dot important for FM screening? I've heard that if you image AM dot with Square Spot, the result is a stair stepped dot. AM dot imaged with conventional Gaussian laser technology results in a smoother rounder dot. But with FM isn't the sharper, steeper dot important? I remember in the old film days, with the Eray, Raystar and Dolevs , we were always striving for the sharpest, hardest, high contrast dot possible with out any fringe. Is this not still the case with CTP?

Thanks

Dan

 

[gordo]

Re: Square Spot versus Gaussian laser technology

Apologies for the double post.

Dan you are correct - the industry has always been striving to have the sharpest, hardest, high contrast dot possible with out any fringe. And this is one of the reasons for the development of SQUAREspot imaging - it has been written up in a TAGA paper and did win a GATF Tech award.
SQUAREspot does not refer to the shape of the halftone dot. It refers to the steep energy profile of the exposing laser ("square to the surface of the plate"). It is a 10,000 dpi laser. The sub-pixel resolution provides an extremely steep energy slope, which in turn provides greater consistency in plate imaging when conditions such as plate and coating thickness and sensitivity as well as processing chemistry naturally vary.
This shows graphically what I'm trying to describe.

!http://www.bytephoto.com/photopost/data/500/10692G_vs_SS.jpg!

AM, FM, and XM dots - round, elliptical, square, FM or whatever shape are built using those pixels as building blocks. The ability to accurately and consistently control the halftone dot edge is critical for printers who do high frequency AM, XM or FM type screens since the smaller the dots are the more they are affected by process variations. SQUAREspot imaging allows these printers to image those types of screens in a reliable consistent manner. We even have printers taking advantage of the technology by printing 10 micron Staccato - some for 100% of their work and something that would not be possible if there was any variation in plate imaging.

Also, SQUAREspot imaging makes use of the integrated energy from 19 laser emitters. In the unlikely event of the failure of a laser emitter, the CTP device automatically compensates and, unlike the Screen device, there is no reduction in throughput or productivity. Even if a second or third laser emitter fails, there is still no reduction in throughput or productivity.

best, gordo