Holographic mode conversion for transmission lines

An electromagnetic mode converting structure comprising:

• a dielectric structure configured to transform an input field distribution of electromagnetic radiation in a first mode to an output field distribution of electromagnetic radiation in a second mode that approximates a target field pattern, the dielectric structure having a volumetric distribution of dielectric constants selected using an optimization algorithm in which real and imaginary parts of dielectric constants in the volumetric distribution of dielectric constants are treated as individually optimizable variables.

An electromagnetic mode converting transmission line junction for a finite frequency range comprising:

• a dielectric structure configured to transform an input field distribution of electromagnetic radiation in a first mode to an output field distribution of electromagnetic radiation in a second mode that approximates a target field pattern, the dielectric structure having a volumetric distribution of dielectric constants selected using an optimization algorithm in which real and imaginary parts of dielectric constants in the volumetric distribution of dielectric constants are treated as individually optimizable variables.