High color purity plasmonic color filters integrating Fabry Perot interferometer with distributed Bragg reflector

We present a novel nano structure which combines a Fabry-perot interferometer (FPI) with a plasmonic color filter (PCF) to enhances color purity without increasing fabrication complexity. In the suggested structure, the additional optical resonance operates independently of plasmonic resonance. An FPI was selected for its strong resonance with minimal layers, effectively addressing the wavelength-dependent cavity thickness problem. By optimizing higher-order resonance modes within the FPI, we achieved one cavity of structure with selective transmission peaks at red, green, and blue wavelengths, significantly increasing the color gamut by 118.35 % improvement. While the metal-based FPI with PCF (MPCF) exhibited limited peak transmittance due to ohmic loss, the optimized dielectric based FPI with PCF (DPCF) achieved higher transmittance up to 46.81 % and superior color selectivity with a narrow FWHM of 16 nm in blue filter. This led to a 120.29 % enhancement in color purity. Our findings highlight the potential of DPCFs in high-resolution imaging devices, offering a robust alternative to conventional color filters. Future work will focus on optimizing fabrication and exploring materials for further enhancement.