Background info:
My colleagues and I are attempting to upgrade a past 3d printer project. Its a SLA type printer using a DLP projector as a light source. It’s got a bottom-up approach.
My question is in regards to shortening print time: A strategy I came up with is replacing the DLP projector (~2000 lumens of white light) with a 100W LED (UV 400nm) and regular color LCD setup with a collimating lens .
Our intended print object is roughly 6x6 inches maximum in area.
Our current print speed is 50 microns/second for an area of 1x1inch
How viable is this setup in printing faster than the original setup?
Am I also right in thinking the unused light spectra (non-uv) ends up as wasted heat in the resin ?
I haven’t actually had much experience in DLP printers, but recently I’ve been researching them heavily in the hopes of building one. As I understand fromyour post, you want to replace the DLP projector with an LCD projector powered by an UV LED? From what I’ve garnered through my research, that would in fact drastically increase cure times. DLP projectors work so well since the actual display element of it, the DMD chip, lets through the light straight from the source with no coloring or filtering whatsoever, so all you would have to do is remove the color wheel and the UV filter and you’d have pure, unadulterated light from the lamp. The white light from the lamp actually contains light from a wide spectrum, including blue light in the low 400nms and possibly a bit of UV light around 400-380nm, and since none of that spectrum is lost through the DMD chip, you can often use a DLP projector as-is with minimal modifications (removal of the color wheel and UVfilter). LCD projectors are different. The function of the LCD is to color the light going through, which, in the way that light works, is to block all wavelengths except the wavelength of the color(s) that it is set to. This means most of the UV light is absorbed by the LCD itself even if it manages to pass the UV filter or if the UV filter is removed. No matter how strong of an UV LED you use,most of what you’d be getting is (much fainter) light in the visible spectrum. Instead, I think the best way to improve cure times in your case is to replace the lamp in your current DLP projector with a UV LED. That should actually fulfill the purpose of intensifying your UV output. Just my two cents. Keep in mind this is all based on my research, not experience, and I could be wrong with everything I said.
