M.S. Thesis Presentation by Benay Sager
Monday, November 25, 2002

(Dr. David Rosen, advisor)

"A Method for Understanding and Predicting StereoLithography Resolution"


StereoLithography (SLA) is a layered manufacturing process during which cross sections of a CAD model are scanned onto a liquid photopolymer by using an UltraViolet (UV) laser. SLA technology has been increasingly used to manufacture more accurate parts with finer details. Being able to make micron scale features using SLA machines is a growing desire expressed by various industries including MEMS. Before more accurate and micron scale features could be built, the SLA process resolution needs to be further understood

In this StereoLithography resolution study, a number of issues were investigated. These issues were:

  1. Categorization of build affecting parameters into the groups of process-inherent and software-imposed.
  2. Identification of resolution issues in horizontal platform (x-y direction) and vertical (z) direction.
  3. Quantification of StereoLithography build resolution in the horizontal platform.

It is equally as important to know what the shape of a StereoLithography cross-section would look like before a part is built. Knowing the shape of a particular cross-section would aid designers in foreseeing build resolution problems that might occur during a StereoLithography build. A method based on offsetting algorithms that will help predict what a cross-section would look like before it is built in the horizontal platform is presented. By using this method, it will be possible for designers to pick certain build parameters that would yield the best possible cross-section and foresee build resolution issues.