General optimization of tapered anti-reflective coatings

An efficient, general optimized method is outlined that achieves antireflective tapers using lossless, non-dispersive dielectrics. The method modifies the derivative of a perfect antireflective wave amplitude distribution rather than the index of refraction distribution. Modifying the derivative of the wave amplitude distribution minimizes the potential index of refraction distributions and ensures perfect antireflection at one frequency, incidence angle, and linear polarization combination. Additional combinations of frequency, incident angle, and linear polarization can be targeted at a particular reflection coefficient within the optimization. After the method is outlined, three examples are shown with one being fabricated and validated at radiofrequencies.