An easy-to-build, accessible volumetric 3D printer based on a liquid crystal display for rapid resin development

Additive manufacturing has revolutionized the way prototypes and one-off parts are produced, but standard additive manufacturing techniques such as material extrusion or vat photopolymerization still present various issues like high print times and defects due to the layer-by-layer nature of the print process. Computed axial lithography (CAL), a novel volumetric additive manufacturing technique, solves many of the issues associated with traditional 3D printing, like staircasing defects and long printing times. However, state of the art CAL requires complex optical setups, limiting access to a working machine, greatly reducing the pace of new material and technologies being adapted to CAL. The Liquid Crystal Display-based computed axial lithography (LCD-CAL) setup here presented keeps many of the advantages of CAL, but utilizes a single lens and an LCD for its optical setup. By moving to LCDs, the machine cost is greatly reduced, and the extremely simplified optical setup of LCD-CAL makes CAL widely accessible. To highlight the versatility of the developed LCD-CAL, we design and characterize two high-viscosity resins for CAL printing based on highly crosslinked and bio-based acrylates, respectively. This work paves the way for widespread adoption of volumetric 3D printing by making a low cost, high speed CAL printer available.