3D Printed Ceramic Lattice Architectures Toward Microwave Luneburg Lenses

Additive manufacturing of ceramics is revolutionizing the field of electromagnetics by providing functionally graded volumes in which lattice density can be controlled within a 3D volume. Periodic structures can now be 3D printed in electromagnetically-low-loss materials such as alumina. By modulating strut sizes within individual unit cells in a larger lattice, the density of a structure can be spatially varied arbitrarily by changing the ratio of ceramic material and interstitial space within each cell. The variations in density directly impact the effective permittivity for RF wavelengths of interest (typically between 5 and 10 times the length of the lattice unit cell size). In this study, four lattice architectures (Oct Vertex Centroid, IsoTruss, Fluorite, and Kelvin) were printed with vat-photopolymerization additive manufacturing to explore the printability of lattice volumes with relevant unit cell dimensions to yield a wide range of effective permittivity values enabling future development of novel ceramic lens structures.