Flat Far Field Lenses and Reflectors

We present a ∞at lens design that provides focusing with no aberration. By proflling the refractive index of the lens to generate a spherical wavefront at the exit side of the lens, the transmitted flelds converge at a specifled focal point. The focusing is achieved using primarily the dispersion phenomenon. We show through numerical examples that focusing without aberration can be achieved at a speciflc frequency and that focusing is possible over a narrow range of frequencies providing that the dispersion is minimal. Additionally, we show that the same principle used to design the lens can be used to design ∞at re∞ectors with a focal point focusing.