采用三维时域有限差分(finite-difference time-domain,FDTD)算法模拟了由十字叉形开口的金膜周期结构组成的红外带通滤波器光谱性能。该算法采用Z变换技术利用Lorentz-Drude模型、Drude模型和理想导体模型描述了金膜在红外频率的介电常数,模拟了红外带通滤波器的透射性能,同测量结果进行了比较。结果表明,利用Lorentz-Drude模型计算的透射率同测量数据吻合得良好。

Models Effect on the Spectral Behavior of Infrared Bandpass Filters Using a Three-dimensional FDTD MethodWANG Lin~1,ZHOU Xian-ting~1,ZHANG Lin~1,QIANG Rui~2 (1.School of Information Engineering,Wuhan University of Technology,Wuhan 430070,China;2.Department of Electrical and Computer Engineering,University of Houston,Houston,USA)Using a three-dimensional finite-difference time-domain(FDTD)algorithm modeled the spectral behavior of infrared bandpass filters consisting of the openings of cross-shaped period structures in a thin gold film.This algorithm incorporates the Lorentz-Drude models and Drude models and perfect electrical conductor(PEC) models to characterize the electrical properties of thin gold film in IR frequencies,and simulates the transmission properties of infrared bandpass filters,then compares with measured data.The results show that the Lorentz-Drude models can accurately describe the frequency-dependent permittivity of the thin gold film at IR frequencies,and the computed transmission spectrum in Lorentz-Drude models is excellent agreement with measured data.FDTD;modeling and simulating;infrared bandpass filters