Internal light pipe geometry can be embedded inside a larger
model that has its own independent form-factor, such as a
character (Figure 3), mobile device (Figure 4), or tangible
chess piece (Figure 5). As each light pipe can be precisely
fabricated at a given location, the process of light pipe routing to avoid intersections becomes a well defined software
problem. One current limitation of 3D printed light pipes
fabricated on the machine we have available is imperfect
light transmission with longer pipes or pipes that curve significantly. We outline the characteristics of this light loss in
the Discussion section. We have designed around this limitation to produce functional prototypes, but envision our techniques can be expanded using future 3D printers that are optimized for optical performance.