Planar asymmetric nano-resonators for highly angle tolerant trans-reflective color filters

This work presents a technique for the design of trans-reflective optical color filters employing a hybrid plasmonic nano-resonator with a dielectric cavity. The proposed filters exhibit wide-angle operation. They offer almost an omnidirectional field-of-view (FOV) (0°∼70°), an essential feature for light collection in miniaturized devices. Moreover, the proposed filters exhibit relatively high transmission and reflection (80%–92%) with at least a 14.3% enhancement than presented in literature. Moreover, the proposed filters are polarization independent manifesting a polarization dependent loss (PDL) of (−0.17 to −0.5 dB) at angle of incidence (AOI) of 70°. Variations in design parameters are introduced to evaluate the equivalent filters performances. Design rules of the filter are presented with physical justifications of the obtained performance curves, hence deducing design guidelines for the proposed color filters that may be further applied in infrared (IR) spectral region.