27 March 2013 Design and fabrication of an RF GRIN lens using 3D printing technology
Author Affiliations +
Electromagnetic media and metamaterials have been explored in frequency regimes ranging from the acoustic to the visible domain over the past decade. A large part of the design, fabrication and prototyping of such materials has focused on planar structures and devices have been demonstrated primarily for certain propagation directions and/or defined polarization. Here, we present the design of a focusing GRadient INdex (GRIN) lens that operates at RF frequencies and is not polarization constrained. We compare the theoretical and experimental results from this lens designed to operate at X-band and fabricated using 3D printing technology to implement the effective medium. The lens with radially varying refractive index gradient was designed, optimized and analyzed by conducting full-wave simulations finite-element method based software. The permittivity was estimated by effective medium theory and calculated using HFSS®. The optimized design was used to fabricate the GRIN lens with isotropic, inhomogenous dielectric material. The refractive index was designed to match the theoretical results using mixing ratio of air/voids and a polymer. Further, we used the refractive index profile to predict the rays’ trajectories and focus length to compare them to those predicted by the FEM simulations. The field distributions were also analyzed to compare performance of the theoretical design to the fabricated lens and were found to be in good agreement with each other.
© (2013) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
J. W. Allen, J. W. Allen, B.-I. Wu, B.-I. Wu, "Design and fabrication of an RF GRIN lens using 3D printing technology", Proc. SPIE 8624, Terahertz, RF, Millimeter, and Submillimeter-Wave Technology and Applications VI, 86240V (27 March 2013); doi: 10.1117/12.2000708; https://doi.org/10.1117/12.2000708


Back to Top