Stereolithography (SLA) was invented by Chuck Hull in the 1980’s and formed the basis for founding 3D Systems, one of the leading companies in the industry. Since that time, there have been multiple variants of 3D printing technology, but all fundamentally using the process of curing a photo-sensitive material with light.
There are other additive manufacturing methods, like fused deposition modeling (FDM), selective laser sintering (SLS) and binder jet printing (BJP). They all work with the same basic premise of taking digital data and building a part layer by layer and they all have their unique advantages and disadvantages.
Photopolymerization as a category has the core advantage of allowing higher resolution and surface finish. It is why it is often the approach of choice in industries like dental, hearing aids, jewelry and other high quality applications. Historically, the negative with photopolymerization was a limitation in the range of materials available and the ability to mimic engineering grade plastics. That has begun to change in recent years as new companies have entered the market, thus bringing forward the possibilities of combining the advantages of this method (high quality) with the materials needed for end-use applications.
The ability to get high resolution, accuracy and precision is dependent on multiple factors. These include (1) the resolution of the optics, (2) the precision of the mechanical systems in the machine, (3) the control of the exposure and the resultant curing, (4) the interaction between the part and required support structures and (5) the overall size of the part and the ability to control tolerances across the build.
In this white paper, we will compare three 3D printing technologies, laser-based SLA, Digital Light Processing (DLP) and Projection Micro Stereolithography (PμSL) based on the five factors listed above.