Tunable color filter with surface plasmon resonance using organic photorefractive composite

We report on a tunable color filter with surface plasmon resonance (SPR), excited by a photorefractive (PR) diffraction grating. When a white light was incident at the diffraction grating formed by a PR effect, the SPR generated at a metal-dielectric material interface was absorbed, and the reflected light showed a complementary color. When the period of the PR diffraction grating was modified by alteration of the optic configuration, the wavelength at which the SPR excitation led to a reflection minimum changed and the spectrum of the reflected light also changed. A well-known equation was used to help us understand the experimental results. All experimental results are in good agreement with the calculation predictions. This result could lead to a new type of tunable color filter.