Design and analysis of multi-channel narrow-band polarization filter

A centrosymmetric structure containing anisotropic medium is proposed. The polarization filtering property of the structure is studied systematically by the transfer matrix method. The results demonstrate that transmittance, isolation and FWHM of transmission spectra are influenced by period N. FWHM is also influenced by incident angle. In addition, center frequency and frequency spacing are determined by incident angle and thickness of medium cavity. On this basis, a detailed design example is given. Isolations of transmission spectra of TM-polarized light and TE-polarized light respectively are 40.46dB and 42.37dB.Transmittances of them respectively are higher than 99.209% and 97.594%. Their center frequencies of transmittance windows accord with the ITU standard. The structure is very simple and transmission spectra of TM and TE polarized lights are completely separated. It is easy to be accomplished and will have worthiness in practical application.