SLA .SLA was invented by American 3DSystems Company in 1986, and then commercialized. SLA technology uses photosensitive resin to polymerize under ultraviolet irradiation to form three-dimensional entities layer by layer. Compared with other 3D printing technologies, SLA has the advantages of high precision, good surface quality and fast processing speed, so it is widely used in industrial design, jewelry, medical care and other fields.