A dielectric-film waveguide with a grating etched on its film–cover interface can be used as a polarization converter. The <i>e</i> wave can be converted into the <i>h</i> wave and vice versa if the guided wave is incident obliquely to the grating vector. The polarization converter is analyzed by use of a quasi-optic technique. A high degree of polarization-conversion efficiency is achieved by a suitable choice of the grating length. The Bragg angles of incidence and observation, the maximum polarization-conversion efficiency, and the frequency and the angular selectivity are all found to increase with an increase in the grating period. An illustrative numerical example is presented.
© 2001 Optical Society of America
(230.3120) Optical devices : Integrated optics devices
(230.5440) Optical devices : Polarization-selective devices
(260.5430) Physical optics : Polarization
(310.2790) Thin films : Guided waves
S. R. Seshadri, "Polarization conversion by reflection in a thin-film grating," J. Opt. Soc. Am. A 18, 1765-1776 (2001)