A Method and Apparatus for Volumetric 3D Printing

Technology

This invention provides an improved way for performing SLA 3D printing that produces objects of a finer quality more quickly in a more scalable manner. It uses a microdisplay to generate an image and an array lens that replicates the image to form a kaleidoscopic imaging pattern on a resin that forms the 3D printed object. The use of array-to-array imaging rather than one-to-one or one-to-array imaging introduces scalable printing at tens of centimeter2 scales without requiring specialized instruments such as scanning modules or mechanical stages. Projection-based SLA multiplies small feature sizes of several micrometers with a kaleidoscopic imaging system that reconstructs patterns over a large area.

Problem Addressed

Coupling lithographic patterning with photopolymerization can create complex structures by sequential stacking of multiple layers. This process known as stereolithography (SLA) suffers from low scalability and a limit on the feature size of complex microstructures. A multi-focal point method has been approached to extend the fabrication area of two-photon polymerization SLA. This approach increases the fabrication area and reduces printing time but, the imaging optics still use a conventional one-to-one or one-to-array imaging system, thus the system still requires a serial scanning process. This limits the potential of scalable SLA due to the intrinsic lithographic scaling law of imaging systems. There is a need for scalable 3D printing systems that allow for large scale efficient printing without an undesirable loss of quality of the printed object.

Advantages

• Use of one, sub-divided, light source lowers cost and complexity of operation
• Increased scalability with use of array-to-array imaging system
• Decreased restrictions on feature size

Publications

Seok Kim, et al. Scalable additive manufacturing via integral image formation. Cornell University.2019 Nov 10.