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Improved selectivity of optical transmission through cascaded waveguide-metal-grating filters

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 نشر من قبل Jerome Le Perchec
 تاريخ النشر 2021
  مجال البحث فيزياء
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 تأليف Jerome Le Perchec




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The resonant transmission of two near-field coupled, cascaded band-pass filters, based on metallic stripe or patch gratings, is analysed. The response, in terms both of maximum efficiency and light rejection out of the resonance, overpasses the simple convolution of the responses of two isolated filters, while keeping good angular tolerance. Illustrations are given in the infrared range where sizing and technological integration of such compact structures are particularly relevant for detection applications.



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