Build Your Own SLA/SLS

Hello guys! First post here! Really need you guy's help.
I'm building a laser resin reprap as my school project, and I'm struggling with getting the laser to on every time it is supposed to 'extrude', and off when it is supposed to retract/do nothing. But since stepper motors are driven by rapid pulses, while lasers are driven by a steady on state, this seems pretty difficult. how should i go about replacing the extruder stepper motor with a laser? Ive been analysing my Marlin code but i'm not sure what to change.
I know that there are modified firmwares that already do this, but assuming I want to modify my own firmware, how should i go about doing this?

Regards,
John

I would contact Dean from mUVe. Super nice guy and has a laser based SLA working great off RAMPS with Marlin.

Clinton

I'd like to say that over the past few days, I've been working with Jeff from MacPod to integrate the LaserShark galvo driver board into CW. The LaserShark board provides a raster display of 4096x 4096 images. In CW, I'm treating it as a new display type. I received my LaserShark board Saturday in the mail, I've already created a new custom plugin to handle driving the display. I expect to be finished up with it in the next week or so before I make an official announcement.
-S

Steve question on the Laser based SLA. Isn't the XY resolution approx. 2.5-3X lower than a standard 100 micron XY on a DLP based printer? All the specs I have read on the various laser based SLA printers suggest they are at best 250 micron XY. The only ones I found better were professional grade printers. Is there a reason to move to this type of printer? Again just curious on this.

Clinton

As I mentioned, Creation Workshop will work with the LaserShark board purely as a 4096x4096 raster display, the rest of the electronics with be the standard Ramps compatible setup. Last night I made huge progress in writing 95% of the code. I can control the 'control' interface of the LaserShark board, I'm still working on the USB 'data' bulk transfers of the image samples now.

May well be talking rubbish here, but can the firmware be configured for dc extruder, if so a relay would work, else, could the frequency of the stepper pulses be used to control laser power, F to V,
or a frequency switch, (comparator)