Theory and Implementation of Volumetric 3D Printing

We discuss Volumetric 3D Printing, a type of additive manufacturing in which 2D patterns of light are projected into a rotating volume of photosensitive polymer material. The temporally-separated, spatially-overlapping patterns crosslink the material, resulting in an arbitrary (to within voxel resolution) 3D distribution of conversion within the material. We describe theoretical limitations to the method, experimental implementation, and how the coupling of optics and materials informs system design. Polymer design requirements such as viscosity and absorptivity are reviewed, as well as optical requirements including wavelength choice, brightness, and speckle mitigation.