Better 3D Printing Through Holography

When most of us think about 3D printing, we usually think about a machine that melts plastic filament and extrudes it through a nozzle. But we all know that there are other technologies out there that range from cutting and laminating paper, to printing with molten metal or glass. Many of those are out of range for the common hacker. Probably the second most common method uses photo resin and some light source to build the layers in the resin. Researchers at Lawrence Livermore National Laboratory (LLNL) and several universities are experimenting with a new technique that exposes photo resin using three lasers, printing an entire object at one time. You can see a cube formed using the technique in the video below.

In all fairness, the process really isn’t holography but LLNL refers to it as “hologram-like.” In fact, it appears the lasers project more like an oblique projection (you know, like in drafting) which is considerably simpler. Simple enough, that we can’t help but wonder if the hacker community couldn’t develop machines based on this principle. The key would be arranging for the resin to only cure where laser light overlaps.

In addition to being fast, the researchers note that because the object forms all at once, it doesn’t have problems associated with layering or being formed in a particular direction. The technique has printed beams, planes, struts at arbitrary angles, lattices and complex curved objects.

There’s clearly work to be done to improve the process. Complex objects would require lots of lasers. There is also a fine balance between underexposing the resin and overexposing it. Better laser controls and better photo resins would help, but there are doubtlessly new techniques to develop, as well.

The hacker community contributed a lot to the growth of fused deposition 3D printing. It would be great to see hacker innovation on this technology as well.

LLNL does a lot of interesting things with 3D printing. If you want to look at what conventional laser resin printers can do, check out the Midwest RepRap Festival.