The Gouy phase shift reinterpreted via the geometric Fourier transform

摘要

Although first discovered over a hundred years ago by the scientist of the same name, the Gouy phase anomaly continues to awaken considerable interest in the scientific community. In this work, the authors analyse this phenomenon in the framework provided by the geometric Fourier transform, first introduced by Wyrowski [Wyrowski and Hellmann, The geometric Fourier transform, In Proc. DGaO, A37, 2017]. The resulting interpretation of the Gouy effect turns out to be logical, coherent and straight-forward, and beautifully simple, and brings to the fore the vital role of the Gouy phase in the unification of the geometrical and diffractive branches of optics.