Metamaterial lens design
Journal of the Optical Society of America A
Given a surface which is not necessarily rotationally symmetric, we design a second surface such that the lens bounded between these two surfaces refracts monochromatic radiation into a given point. The lens consists of a material having a negative refractive index. We then generalize a result of Veselago when the given surface is a plane and show that there are times when the second surface can never be a plane.
Cristian E. Gutiérrez and Eric Stachura, "Metamaterial lens design," J. Opt. Soc. Am. A 33, 2020-2026 (2016)