Profile Inversion and Closed Form Formulation of Compact GRIN Lenses

Notes on Profile Inversion and Closed Form Formulation of Compact GRIN Lenses

“…The comparison of the derivation of the results in [1] appears similar to the one in [6] since it is based on the same process that Luneburg used to find his famous solution. The authors of [1] wish to apologize for this oversight; the literature review in their paper was conducted in good faith.…”

“…The comparison of the derivation of the results in [1] appears similar to the one in [6] since it is based on the same process that Luneburg used to find his famous solution. The authors of [1] wish to apologize for this oversight; the literature review in their paper was conducted in good faith. They have derived the solution themselves, being aware (and declaring it in the paper), that could have been done before, since the solution appears several times in the literature concerning fiber optics (but always without appropriate references or applications to antennas).…”

“…In [1], the authors focused on the derivation of closed form formulas based on Geometrical Optics of tapering and spill-over efficiency for a radial refractive index profile of a GRIN lens with integrated feeder, namely a zero focallength lens. The exact closed form of the radial refractive index is well known; but its derivation is not easily found in the literature and the authors have proposed their own derivation in [1]. They state in the introduction of [1]:…”

“…The exact closed form of the radial refractive index is well known; but its derivation is not easily found in the literature and the authors have proposed their own derivation in [1]. They state in the introduction of [1]:…”

“…After the publication of [1] the authors received a few comments [2] that are summarized here, since they appear 1 The authors are with the Department of Information Engineering and Mathematics, University of Siena, Italy (e-mail of the main author: francesca.maggiorelli@ unisi.it). The work is an output of the Joint Antennas Innovation Lab financed between Huawei Technologies Co., and University of Siena.…”