基于矩形金属块阵列结构的等离子体颜色滤波器

Plasmonic Color Filter Based on Rectangular Metal Block Array Structure

设计了一种基于矩形金属块阵列结构的等离子体颜色滤波器,该器件结合表面等离子体共振效应与平板波导的导波特性,利用非对称矩形金属块周期性阵列结构对入射光偏振敏感的特点,在可见光波段实现对透射谱的动态调控。采用时域有限差分法研究了阵列周期、填充因子、电介质层与金属层厚度、入射光偏振角等参数对透射谱及其滤色特性的影响。结果表明,通过改变矩形金属块阵列周期参数可静态调控透射谱;矩形金属块阵列周期不对称时,通过改变入射光偏振角可对透射谱进行动态调控。通过调节结构参数,得到滤波器在可见光范围内的透射率可高达75%,且可同步实现对滤出颜色的静态和动态调控。该研究为下一代颜色可调谐等离子体颜色滤波器的设计提供理论依据。

In this paper,a plasmonic color filter based on a rectangular metal block array structure is designed.The device combines the surface plasmon resonance effect with the guided wave characteristics of planar waveguides,and realizes the dynamic control of transmission spectra in the visible light band by using the polarization sensitivity of the asymmetric rectangular metal block periodic array structure for the incident light.The effects of the array period,filling factor,thickness of dielectric and metal layers,and polarization angle of incident light on transmission spectra and color filtering characteristics are studied by using the finite difference time domain method.The results show that the transmission spectra can be adjusted statically by changing the period parameters of the rectangular metal block array and can be controlled by dynamically changing the polarization angle of the incident light when the period of the rectangular metal block array is asymmetric.By adjusting the structural parameters,the transmittance of the filter can be as high as 75%in the visible light range,and the static and dynamic control of the filtered color can be realized simultaneously.This research provides a theoretical basis for the design of next-generation color-tunable plasmonic color filters.