Differences in 3D printing with light-cured resins: SLA vs. DLP and UV LCD

3D printing using light-cured resins includes various methods, and each of them has its own unique features and applications. When considering SLA (stereolithography), DLP (digital light printing) and UV LCD technologies, it is important to understand how each affects the printing process and the final print quality.

SLA technology (stereolithography) uses a laser to harden resins layer by layer. In this method, a very precise laser beam scans the resin surface, hardening it point-wise. This allows for exceptional precision and the ability to create very detailed objects. The SLA laser can harden very small areas, which translates into high detail accuracy and smoothness of the print surface.

Unlike SLA, DLP and UV LCD technologies work slightly differently. Both of these approaches use light sources to cure entire layers of resin at once. In DLP, a digital projector creates an image of each layer which then cures the resin, while UV LCD uses LCD screens to transmit UV light which cures the resin. While these methods are typically faster than SLA because they harden the entire layer at once, they can be less precise. The light emitted by LCD screen pixels can scatter, creating a halo effect that affects the sharpness of details.

Additionally, DLP and UV LCD technologies experience greater model shrinkage compared to SLA. The sudden photopolymerization of the surface in these methods causes greater shrinkage than the gradual hardening of the paths of each layer, as is the case in SLA. This can be particularly problematic in precision applications where high dimensional accuracy is required.

Technology Applied – the largest company providing 3D printing services, uses SLA technology from DWS Systems, offering customers higher quality and precision in 3D resin prints. The choice between SLA, DLP and UV LCD depends on the specific requirements of the project. If speed and cost are key, DLP and UV LCD may be the preferred methods. On the other hand, for projects that require exceptional precision and detail, SLA will be the best choice. Understanding these nuances allows Technology Applied to provide clients with tailored solutions, leveraging the strengths of each technology to meet a variety of design requirements.

Photo: www.ta.parts