3D / Dynamic focusing Fiber Laser

[jeremy powel]

Does any one here have or used a “3D” fiber laser it is supposedly able to be focused and able to stay in focused over uneven objects it looks like up to about 2 inch. Some how it is able to maintain focus on the Z axis. This is the best website I have found for info. https://www.google.com/amp/s/amp.stylecnc.com/fiber-laser-marking-machine/3D-laser-marking-machine-with-IPG-fiber-source.html
I have been questioning the hell of out multiple people sales people. Of course they aren’t going to tell you anything that might not make a sell. I have gotten quotes all over the place from multiple vendors.

[John Lifer]

There is at least one person here that bought one last year. Do some searching and he should pop up. Don't know if he's still on line. I think he was doing medical bracelets......

[Steve Utick]

I have a 3D MOPA Fiber here. Only had it for a couple of months, so still VERY early into learning stages. Haven't done a whole lot using the 3D capabilities yet, but happy with it so far from my limited testing. Definitely WAY more of a learning curve for fiber than CO2, that's for sure. One of the downsides, is that the 3D fiber I have doesn't use EZCAD, but is similar enough that I can use most of the tips that are posted here as well.

[Bert McMahan]

Keyence makes one I think. I've never used it but you may be able to find some literature online.

[Kev Williams]

I would be interested in one, but it seems to me that, because a galvo beam emanates from a single center point and angles outward from there, that running into beam interference would occur more than I'd like. As in, suppose I have a 6x6" part with a 4x4" x 2" tall block sitting in the middle, and the lower part needs engraved 1/8" from the raised block- This isn't going to happen...
380012
...because the top of the upper section will block the beam. This is drawn to scale based on my 150mm lens, the effect would be less longer lenses, but using a 100mm lens the interference would be much more pronounced.

This of course assumes these things work essentially the same as non 3D machines...

I get parts similar to this quite often, usually Delrin...

[Dave Sheldrake]

What your on about is X-Y parallel projection galvanometer scanning, it was developed for curved surfaces more than actual stepped 3d surfaces to take into account the differences in a form when transposed from 2D to 3D. Like all Galvo systems they still work line of sight so Kevs stuff won't work even on a PPGS. They only really work on free form surfaces (picture the surface of a load of waves in the sea).
It's a calculated way round dealing with depth of field via use of a telecentric lens system that maps a 3d surface onto a 2d constant magnification lens.

In Jeremys original post link there is a video, if those steps were reversed (so rising from left to right rather than right to left) the machine wouldn't be able to do them. They only work when the lowest point of the engraving is under the centre point of the optics unless you are dealing with very shallow curves.

Caveat: Unless you work with multiple optic systems that will cause the beam to exit from the lens at 90 degrees over it's entire surface