SUMMARY

Additive manufacturing (AM) has experienced a surge in popularity over the last decade due to the ability to fabricate complex structures with unique functional properties. One promising AM technique is digital light processing (DLP), which uses a UV light source to solidify a liquid resin into a solid part in a layer-by-layer manner. Because full layers are fabricated at once, DLP is very fast compared to other methods, and pixel-by-pixel control of the projected light pattern means it is also very accurate. In a method known as grayscale DLP (g-DLP), each pixel can be assigned a unique grayscale value, which allows for the local control of the mechanical properties of the printed part. There are several factors that limit the achievable resolution of local property control including diffusion, overlapping light fields, and light penetration. In this work, the g-DLP process is used to show how local control of material properties can be used to create novel mechanical behaviors. The g-DLP curing process is modeled to gain a better understanding of the resolution limitations and make improvements. Finally, this information is leveraged to optimize both the shape and the property of printed parts. This work introduces several new applications for g-DLP printing, and it provides fundamental insights into the curing process. The improvements to the achievable g-DLP feature size could have a fundamental impact on the quality and scale of parts achievable using AM.