摘要
用时域有限差分法(FDTD)和傅里叶变换分别计算了TE、TM波入射时,一维金属光栅的夫琅和费衍射场分布,计算结果表明,当光栅常数小至波长量级时,衍射场明显与光的偏振态有关,而且衍射场分布与光栅周期和缝宽有关,标量衍射中的缺级现象消失.另外,在光栅常数大于波长量级的情况下,如果光栅的缝宽或不透明部分的尺寸接近波长量级时,衍射场也出现明显的偏振相关性.
Abstract Diffraction fields of one-dimensional transmission metal gratings for TE and TM waves were calculated and analyzed by finite difference time-domain （FDTD） algorithm and Fourier transform. Calculated results indicated that diffraction field was obviously polarization dependent with grating period on the same order of magnitude as the wavelength. Diffraction fields of both TE and TM waves were influenced by period and width of grating. Consequently as predicted by the scalar theory vanished orders appeared. In addition, with grating width or width of opaque portion approaching the wavelength, diffraction also became polarization dependent, even when period of grating was much larger than the order of magnitude of wavelength.
出处
《北京师范大学学报（自然科学版）》
CAS
CSCD
北大核心
2008年第4期376-379,共4页
Journal of Beijing Normal University(Natural Science)
基金
国家自然科学基金资助项目(60677006)
关键词
光栅
偏振特性
FDTD算法
grating
polarization property
FDTD algorithm
