3D Systems, Inc.
		26081 Avenue Hall
		Valencia, CA  91355
		(805)295-5600 (805)257-1200/Fax
Makers of the Stereolithography Apparatus (SLA). Stereolithography is the liquid-based rapid prototyping technology. The Apparatus solidifies a CAD model from an acrylic polymer resin which catalyzes (hardens) when exposed to ultraviolet light.

The SLA-500 has a build capacity of twenty inches.

The host computer calculates sequential, horizontal (constant Z) cross-sections of the given CAD model. The SLA uses the surface of the liquid to define a flat, horizontal plane in real space. The ultraviolet laser beam is focused to catalyze the resin to a precise slice depth below the surface.

The elevator platform begins a slice depth below the surface. The first slice exposed is a support structure which will attach the CAD model to the platform. When the slice is exposed and hardened, the platform dips below the surface and the hardened layer is covered with another slice thickness of liquid. The next exposed layer, as it hardens, fuses to the previous layer. The process continues, "growing" the object downward into the resin bath.

Here is an example of a Stereolithograph of a mathematical visualization.

See also www.3d.com