1results about How to "High side mode suppression ratio" patented technology

The application discloses a filter based on a multi-mode subwavelength grating. The filter comprises a mode demultiplexer for multiplexing and demultiplexing of a base mode and a high-order mode, a subwavelength grating for weakly binding regulation of a mode field of the base mode and the high-order mode, and a straight-through waveguide for output of the base mode. The application introduces a structure of the subwavelength grating and weakly binding regulation of the mode field, and by virtue of excellent flat dispersion regulation characteristics, the application realizes apodization of the grating while keeping consistent local refractive index of the grating, thereby obtaining the filter with high side mode suppression ratio and no free spectral range limitation, and the filter can realize flat and low-loss spectral response, meets the next-generation large-capacity and high-speed wavelength division multiplexing transmission demand, and has the advantages of simple structure, simple process, excellent performance and the like.