Stereolithography (SLA)

Stereolithography is a 3D Printing process which uses a computer-controlled moving laser beam, pre-programmed using CAM/CAD software. Stereolithography (SL) is an industrial 3D printing process used to create concept models, cosmetic - rapid prototypes, and complex parts with intricate geometries in as fast as 1 day.

The technology was invented in 1986 by Charles W. Hull, who co-founded 3D Systems Corp. The first stereolithography machine was capable of creating small two-dimensional shapes. However, over the years the technology has evolved and progressed to where it is today.

Stereolithography works by using a photopolymer resin that is cured by exposure to light. The machine traces out the desired geometry layer by layer using a computer-controlled moving laser beam. The beam is directed by mirrors that are positioned around the build platform.

The build platform is lowered into the vat of photopolymer resin after each layer is cured. This process is repeated until the desired geometry is achieved.

The advantage of stereolithography is that it can create parts with very intricate geometries that would be difficult or impossible to create using traditional manufacturing methods. Additionally, the lead time for stereolithography is much shorter than traditional methods such as milling or machining.

The downside of stereolithography is that it is a relatively expensive technology. Additionally, the material properties of the parts that are produced are not as good as those produced using traditional methods.

Overall, stereolithography is a versatile and powerful technology that has a wide range of applications in industry and research.

How it works?                                                                                                                Stereolithography, or SLA 3D printing, is a type of additive manufacturing technology used for creating models, prototypes, patterns, and production parts. SLA printing works by first positioning the build platform in the tank of liquid photopolymer, at a distance of one layer height for the surface of the liquid. A UV laser creates the next layer by selectively curing and solidifying the photopolymer resin. The build platform is then lowered by one layer thickness, and the next cross-section is drawn. This process is repeated until the build is complete.

SLA is an acronym for “stereolithography apparatus” or “stereo lithographic apparatus.” It was invented in 1986 by Chuck Hull, who later founded 3D Systems Corporation. The patent for stereolithography (U.S. Patent 4,575,330) was issued in 1986 and expires in 2004.

The key advantage of stereolithography is its accuracy. SLA is capable of producing parts with very fine features and detail, as well as smooth surfaces. Additionally, SLA is one of the fastest additive manufacturing technologies, with some machines capable of printing a layer in as little as 12 seconds.

Resin 3D printing i s often used for creating prototypes and models, as well as for low-volume production. Applications for SLA parts include investment casting patterns, medical devices, and eyewear.