Efficient design method for plasmonic filter for tuning spectral selectivity

Nano-structure-based color technologies have been reported as alternatives for conventional pigment-or dye-based color filters due to their simple design methods and durable characteristics. Since structure-based optical resonances accompany multiple resonance modes, spectral selectivity could be degraded. In this work, a simple and effective design of a plasmonic color filter that combines the plasmonic filter with one-dimensional photonic crystals. The introduced photonic crystal provides a photonic band gap, and it helps in suppressing the undesirable transmission peaks of the plasmonic color filter that originates from higher order resonance modes. Finally, the proposed design achieves high color purity. In addition, the simplicity of the design makes it both suitable for large-area fabrication and cost effective. This work is expected to provide a practical alternative to traditional color filters.