Metasurface-based Color Filter with Optical Cavity for High Color Purity Displays

Metasurface-based color filter have been regarded as good alternatives of conventional color filter causes of their reliability, simple design method, and high resolved pixelization performance. In this study, we designed a novel metasurface-based color filter with surface plasmons (SPs). The conventional plasmonic color filters (PCFs) have broad transmittance spectra. Consequently, the color purity degrades and this become a fatal issue for practical use. In order to solve the poor wavelength selectivity of the PCFs, we designed a novel PCF integrated with the Fabry-Perot interferometer (FPI). We added the simple cavity structure over the matching layer of the existing PCF to apply FPI to the PCF. By applying it, the red tail in the long wavelength band of the transmission properties of PCFs were reduced. The color gamut of the suggested filter has increased 2.42 times compared to the conventional PCFs. These improvements are showed the applicability of PCF to various imaging devices.