DLideas 4: 3D PrintingTrevor Hendricks
The DLideas series focuses on current developments in the world of DLP® and emerging applications using the technology.
3D printing, or additive manufacturing, is the process of building a three-dimensional object from a digital file by laying down successive layers of material. Each of these layers can be seen as a thinly-sliced horizontal cross-section of the eventual object. As it evolves, 3D printing is set to transform almost every major industry.
Most of us associate 3D printing with manufacturing industries; however, it is making some of the biggest breakthroughs in the medical space with bioprinting. 3D bioprinting is the process of generating spatially controlled cell patterns where viability and cell function are preserved within the printing construct. Instead of using resins and photo polymers, they inject living cells in tissue.
Not all 3D printers use the same technology. Some methods such as SLS (selective laser sintering) or FDM (fused deposition modeling) use melting or softening material to lay down each layer. Other methods such as SLA (stereolithography) involve curing of the photoreactive by using a UV light source one layer at a time. Lasers can also be used with SLA to cure one pixel at a time as it scans across the layer, or with DLP® the entire area can be processed all at once. Different materials require specific wavelengths of light to cure. By being able to use a DMD to work with the majority of the UV spectrum, you’re able to work with a wide range of materials and as a result, you have a lot more flexibility over choices.
Notably, DLP® printers use liquid photo polymer resins to build objects. The digital micromirror device projects coded light patterns that selectively exposes and hardens the resins for each cross-sectional slice of the object. With DLP®, an entire layer is exposed with a single pattern, therefore fast build speeds are achieved regardless of layer complexity.