J Opt Soc Am A Opt Image Sci Vis
February 2023
In the shadow theory, a new description of electromagnetic fields using scattering factors has been employed. This paper presents a new numerical method based on scattering factors for the scattering problem of a composite dielectric grating embedded with conducting strips. The scattering factors for the primary fields, which are based on the assumption of conducting strips being removed completely and those for the secondary fields generated by the surface electric currents on conducting strips, are introduced.
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October 2020
The stripe of the tropical freshwater fish "neon tetra" consists of many iridophores, in which tilted reflecting platelets are periodically arranged. The neon tetra has structural coloration and changes the color of a stripe in response to the surrounding conditions. The mechanism of the color change is thought to be controlling a slant angle of the platelets and changing the spacing between the platelets.
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November 2018
In the theory of gratings, a diffraction solution must satisfy the energy balance and the reciprocity. This paper examines the diffraction by multilayered dielectric gratings, including lossy layers of which the solutions do not satisfy the energy balance. Applying the shadow theory to the matrix eigenvalues method, the symmetry of scattering factors in the theory and that of diffraction efficiencies are shown in some formulae and then are validated numerically.
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November 2016
Nakayama's shadow theory first discussed the diffraction by a perfectly conducting grating in a planar mounting. In the theory, a new formulation by use of a scattering factor was proposed. This paper focuses on the middle regions of a multilayered dielectric grating placed in conical mounting.
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