Which description defines stereolithography (SLA)?

• A. An Additive Manufacturing Process that Uses a Vat of Liquid UV Resin and UV Laser to Build Parts Layer by Layer
• B. A Process that Sinter Titanium Powder with a Laser
• C. A Process that Deposits Metal Powder with an Electron Beam
• D. A Process that Prints Using a Hot Glue Printer

Answer: (A)

Stereolithography builds parts by curing a liquid resin with light. A vat of liquid UV-curable resin sits in the machine, and a UV laser traces each cross-section of the object on the resin’s surface, solidifying the resin where the laser passes. After each layer, the build platform lowers a small distance and a new layer of resin covers the previous layer, allowing the process to repeat until the part is formed. This approach uses liquid photopolymer resin cured by UV light, unlike powder-based or metal-focused methods that rely on sintering or melting powders with lasers or electron beams. So the description that mentions a vat of liquid UV resin and a UV laser building the part layer by layer is the one that defines SLA.