Microwave focusing and beam collimation using negative index of refraction lenses

Negative index of refraction materials (NIMs) were first postulated by Veselago in 1968 and have recently been realised using structures formed with rings and wires deposited on printed circuit boards. The proof of the existence of negative index of refraction was established using a Snell´s law experiment with a wedge. The predicted and measured refraction angles were found to be consistent for a negative index material and in excellent agreement with the theoretical expectations. For microwave lenses NIMs have the advantage of being lighter, having better focusing properties and potentially lower aberrations. Simulation and experimental results on NIM configurations including gradient index of refraction and spherical 3D lenses are presented. Both focusing and beam collimating applications will be considered. These results will be compared to normal positive index of refraction material lenses