[Fabrication of a 3-dimensional plastic model with photopolymer from CT images]

A new type of the 3-dimensional model fabricating system was developed using a focused laser beam and liquid photopolymer. The system can easily fabricate solid models, without tools, directly from digital data received from medical CT scanners or CAD systems. Solid models are fabricated as follows. After a layer of liquid photopolymer is placed above the already solidified layers, a laser beam is scanned along horizontally sliced patterns on the liquid photopolymer. The parts where the light shone is solidified. And then the solidified layers agreed with the patterns are stacked. This process is repeated for each layer. This paper describes the fabrication of a smoothly natural solid model from an original CT image sequence which is taken with rough pitches. Interpolation between original neighboring sliced images which are composed of extracted contour data is performed by use of the third order spline curve. This method can be implemented using a rather small computer. This technique can play a major role in diagnosis procedure, personal prosthesis design, and surgical operation planning.