Transmissive RGB Colors with High Purity and High Brightness by Quad-Layered Thin Films

We propose quad-layered transmissive structural color filters that can generate RGB primary colors with high purity and high brightness by utilizing interferences in dual Fabry-Perot (FP) cavities. Since there is a trade-off between color purity and brightness in a conventional single FP cavity, a peak separation in multiple FP cavities is exploited to achieve a more square-shaped spectral curve. Besides, controlling a resonance order in each cavity leads to a great suppression of a higher-order resonance for a red color filter. The presented results may be applied to various applications including display panels, decorations, and image sensors.