F-Theta Scan Lenses

Does anyone know anything about F-Theta Lenses?

https://www.thorlabs.com/newgrouppage9.cfm?objectgroup_id=6430

Do you think they would work to prevent barrel distortion? Maybe moai 2.0 or even as an add-on?

Have a look here:

It’s apparently a harder nut to crack than 3DFacture thought, LOL.

barrel distortion is on both x/y axis while galvo distortion is only on one axis, so a standard F-theta lens is unlikely going to work for laser/galvo setup

when should we expect a software update to fix the galvo distortion? Is the galvo distortion on the y-axis galvo?

You can see the distortion in the video linked below.

I will try this gcode tomorrow. I am still very concerned with the accuracy. Does anyone have a grid of the distortion on the build platform. I was also curious to see when this issue would be solved.

isn’t the distortion 3-dimensional? I feel like it should be like a cone starting from the laser, so the higher from the vat the higher the distortion.

It’s 2 dimensional, the z is consistently accurate.

the distortion is on one axis that is inherent in laser/galvo system. We are working on a firmware fix for this. The distortion is more on the edges and you can manage it but not completely eliminate with advanced calibration.

Advance Moai calibration guide:

Thanks for the link being added for the 16th time, since it seems to be the only response to this issue. Still curious when to expect a actual solution. It seems you have been working on this issue for a couple of months, and seriously workin for about 1 month. Is there is any way the community can help, being a open source printer and all? Would it be a firmware fix or cura fix?

We have been approaching this issue from firmware and standalone program since November. standalone program is much more further along and we hope to have a public beta by April. It is not as simple as it may sound because adjustments are non-linear and gcode is represented by lines which would need to broken into small pieces. As soon as we have some publically testable we will share with the community.

From our testing we were only able to get a 70mmx70mm build area within a 100 micron tolerance. I know it has been mentioned that a 100mmx100mm is consistent. Have you also found similar results Mark?

Peopoly-
6 month have passed since the last post.
Have this issue been solved ?
(hard to follow the issue through so many different topics)

Does anyone tried to use an f-theta lense in the moai? I would be very interested to read about your experience.

Hi matt3o,

We go over some of F-Theta lenses’ pitfalls and advantages in this blog article. Please check it out.

John and Victor

Sorry. Meant to include the link. Here goes it.