Direct 3D printing of optical elements with xolography

Xolography is a volumetric 3D printing method utilizing dual-color photoinitiators to fabricate layer-free objects from photopolymer resins, ranging from millimeters to centimeters in size. It enables fast, continuous printing of complex threedimensional objects, which are free of internal interfaces and possess optical-grade surfaces immediately after printing. The development of photobleaching dual-color photoinitiators together with a light sheet configuration, which prevents the evolution of striping artifacts, allows us to 3D print transparent and smooth optical elements within few minutes printing time and without the need for any additional process steps such as coating or polishing. In combination with its capability to print complex freeform geometries and the use of highly viscous photopolymer resins, Xolography has the potential to revolutionize prototyping and fabrication of optical elements.