Reflection characteristics of metal-dielectric-metal reflective-type color filter

Reflection filtering characteristics of metal-dielectric-metal (MDM) structure at visible region are investigated theoretically. The structure consists of 3 parts: the flexible transparent substrate, the metal layer and the dielectric-metal grating layer. By using rigorous couple-wave analysis (RCWA), the reflection characteristics of transverse magnetic (TM) polarized light are analyzed as a function of the duty cycle, the period and the thickness of the dielectric-metal grating. It is found that different colors can be obtained by adjusting the parameters of the structure. Based on the simulation results and the cyan-magentayellow (CMY) color scheme, a high-performance color filter is proposed by optimizing the structural parameters and the 3 prime colors including cyan, magenta and yellow are obtained. The reflection valley and the bandwidths remain almost unchanged over a wide incident angle range of 0～45. The proposed color filter is suitable for filtering used in reflective-type color displays.