What Is Digital Light Synthesis (DLS)?

Digital Light Synthesis (DLS) is a proprietary resin-based 3D printing process developed by Carbon. DLS 3D printing uses the Continuous Liquid Interface Production (CLIP) technology also developed by Carbon. 

How Does DLS 3D Printing Work?

Digital Light Synthesis is based on stereolithography and like that process is also a type of vat photopolymerization. Both processes use UV light to cure resin. Unlike stereolithography, however, Carbon’s DLS 3D printing doesn’t pause after each layer. Instead, the resin continuously flows through a “dead zone” just above the oxygen-permeable window, as shown below. UV images representing the cross-section of the part are projected onto an oxygen-permeable window to solidify the resin. Parts are built upside-down, as the build platform rises from the vat of resin.

What Materials Can Be Used?

DLS resins available from Carbon include elastomeric, flexible, rigid and medical-grade polyurethanes; silicone; cyanate ester; epoxy; urethane methacrylate; and dental materials.

What Postprocessing Is Required?

After printing, the parts are cleaned of resin and freed from the build plate. Any supports are removed. UV-curable resin parts are complete at this stage. Many materials, however, require a thermal post-cure in an oven; this can take from 4 to 13 hours to complete. The heat sets off a secondary chemical reaction that strengthens the parts. Typically no further postprocessing is required after cleaning and curing.

Why Use Digital Light Synthesis?

The continuous nature of Carbon’s DLS 3D printing process avoids the creation of layer lines in the part, offering a surface finish comparable to injection-molded parts. According to Carbon, DLS parts are also watertight and isotropic, having the same strength in all directions.

In addition to providing a means of making prototypes, DLS can be used for bridge production before molds are available, or as an alternative for making production parts that would otherwise be injection molded.

What Are the Applications for DLS 3D Printing?

Digital Light Synthesis has been applied to prototype and produce medical devices; mouth guards and other dental implements; COVID swabs; shoe midsoles; automotive brackets; food service devices; gaskets and other flexible components; parts for space; and more.