Subtractive color filters based coaxial metasurface structures with high saturation and brightness

We propose and numerically demonstrate subtractive color filters (SCFs) based on a plasmonic metasurface including coaxial aperture geometry working in the visible range. The Proposed designs involve arranging coaxial apertures (circular, elliptical, square, rectangular) in a silver film for reflection mode color filtering. By controlling the geometric parameters of the SCFs design, we achieve tunability of high-absorption resonance peaks (> 99.9%) across the visible spectrum. The proposed SCFs are supposed to exhibit a polarization-insensitive operation for symmetric apertures and a polarization-sensitive response for asymmetric apertures. Furthermore, the devices provide a relaxed angular tolerance. Finally, our results are then modeled using nonlinear regression analysis to a cubic regression, and a quadratic exponential model. Accordingly, it is possible to create an SCF for any color of choice in a straightforward way. This technique constitutes a promising process that provides a methodology to design color filters for practical applications such as color printing, high-resolution chromatic displays, and multispectral imaging.