DLP vs. SLA 3D Printers

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Updated January 3, 2023

Consumers interested in resin printing must choose between DLP vs. SLA 3D printers, which may spark discussion of which makes for the best printers. Both of these methods use vat photopolymerization to create designs printed by the user. Resin printers offer excellent details and smooth surfaces compared to their filament counterparts. To find out how DLP and SLA printers work and the differences between them, read on.


  • DLP printers utilize light projectors to cure liquid resin into the desired shape within a vat, building from the bottom up.
  • SLA printers use UV lasers that shine into a resin vat to create the model, working layer by layer.
  • SLA printers should be used for detailed creation, while DLP printers are suitable for larger designs without movable parts.

SLA vs. DLP Printing Process

Just as filament printer users have to choose between ABS vs. PLA for 3D printers, consumers who prefer resin must choose between SLA and DLP printers. The primary difference between the two stems from the light source used to cure the resin. Read our resource guide to DLP vs LCD for 3D printers for more information. Additionally, DLP cures the entire resin layer simultaneously, while SLA printers cure each point on the layer one at a time. However, both resin printing technologies work layer by layer to cure the liquid resin into the desired 3D print. To determine whether you want an ethernet printer vs. wireless, check out our article.

Insider Tip

SLA printers are ideal for printing a highly complex object since the laser size can range from 0.3 mm to 0.15 mm.

How Do SLA Printers Work in 3D Printing?

SLA stands for stereolithography apparatus (SLA) printer, a form of vat photopolymerization 3D printing technology. These devices are a form of resin printer with a UV laser on the bottom of the resin tank of liquid thermosetting resin. The UV light laser beam flashes upward into the vat during printing, curing the material and hardening it. Every point on a layer is exposed to the laser before the printer moves on to the next layer.

To see the differences between two solid 3D printers, read our Prusa SL1 vs Elegoo Mars.

Resin Post-Processing Process

During post-processing, the print is removed from the build platform before being cleaned through immersion in a solvent or ultrasonic bath, removing the uncured resin. The user then removes the printing supports from the structures, and the part is exposed to ultraviolet light. This curing stabilizes polymerization, providing geometry and material properties to the object. Both SLA and DLP printers use these post-processing steps.

How Do DLP Printers Work in 3D Printing?

Digital light processing (DLP) within 3D printing is a technique used to develop a product by flashing an image of the layer’s shape using UV light, instantly curing all points among that layer. The model is created upside down with the design hanging from the print platform into the resin tank. The printer directs the light through the use of a digital micromirror device (DMD.) As with an image, each point within the level is represented by one square pixel that forms the layer’s image when combined.

Comparison of SLA and DLP Printers

  • Speed: DLP technology prints exceptionally quickly because it instantly cures the entire layer. SLA lasers cure each pixel individually, taking much longer. As a result, an SLA print with more parts can take even longer to print.
  • Detail: SLA printers print detailed designs easily, with layer sizes ranging from 0.03 mm to 0.15 mm. DLP is reliable for low-complexity prints with no moving parts. The smallest layer size for these prints is 0.05 mm.
  • Material: Because DLP prints hang into the vat, the volume of material necessary is less as the print lifts out of the small bath each time, resulting in a lower price. On the other hand, SLA requires a large volume of resin as the print lowers into the resin bath on top of the surface of the print bed. Additionally, SLA vats are larger, making them more expensive to fill.
  • Learn more with our guide on resin vs filament 3D printers.


DLP printers cannot print the same level of detail as SLA models can, but they print much faster.


Are all resins compatible with the different printing techniques?

No, you should check which resins are right for your printer within the manufacturer’s website or user’s guide.

What is FDM printing?

Fused deposition modeling (FDM) is a technology used in 3D models that heat and use filaments to create designs with lower print quality than resin printers.

Is SLA faster than FDM?

FDM is typically faster than SLA printing, but it does not have the same level of detail, print quality, or smooth edges.

STAT: DLP cures an entire layer at once, eliminating the time needed to scan the part’s interior, as seen in SLA printing. More parts in a batch do not take more time. (source)

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