面向全息视频显示的深亚波长光栅耦合结构（英文）  

Fabry-Perot Resonance on Aluminum Sub-Wavelength Gratings for Holographic Display Device

作　　者：张明华[1] 沈川[1] 朱文亮 韦穗[1] ZHANG Minghua;SHEN Chuan;ZHU Wenliang;WEI Sui(Key Laboratory of Intelligent Computing and Signal Processing,Ministry of Education,Anhui University,Hefei 230039,China)

机构地区：[1]安徽大学人工智能计算及信号处理教育部重点实验室,合肥230039

出　　处：《电子器件》2018年第4期833-838,共6页Chinese Journal of Electron Devices

基　　金：National Natural Science Foundation of China(61301296,61377006,61501001);Natural Science Foundation of Anhui Province(1608085QF161);Natural Science Project of Anhui Higher Education Institutions of China(KJ2016A029,KJ2015A114)

摘　　要：研究了一种类MIM(Metal-Insulator-Metal)结构,用于全息显示装置,它的关键部分是铝亚波长光栅,该结构可以在可见光范围内调制反射光相位。众所周知,商业化的LCOS(Liquid Crystal of Silicon)是广泛使用的空间光调制器,但是它通过液晶的光程差实现相位调制的机制不利于器件的进一步缩小以达到全息显示所需要的空间带宽。用亚波长光栅结构代替LCOS顶部电极层,虽然几何相似,但它是物理过程新颖的全息显示装置。当入射光进入金属光栅狭缝,一个典型的零阶衍射和深亚波长F-P共振被诱导。腔边缘的反射相位可以被有效地操作使通过由一个薄的中间电介质层构成的MIM结构,因为金属表面等离子激元对周围介质的变化很敏感。而且,为了适应未来视频全息显示的需求,我们研究了动态实时调制的可能性通过改变电介质层的介电常量。通常铝不被认为是有吸引力的等离子体材料,但是它资源丰富、便宜而且与CMOS兼容,被广泛使用在空间光调制器中,例如LCOS。同时,众所周知,铝等离子体特性对材料的几何形状很敏感。然而,我们的亚波长光栅耦合结构有效的克服上述这些问题,模拟结果已经证明当铝光栅中铝纳米棒从140 nm变化到190 nm时,相位调制量的影响很小,甚至可以被忽略,这对于实际制备提供了鲁棒的可能性,同时研究了不同光栅高度对实验结果的影响,仿真结果通过CST软件给出,证明仿真电介质媒介参数在液晶折射率变化率范围内(1.4～1.7)相位调制在可见光范围可以达到0到2π,这为真实器件奠定了基础。One kind of Fabry-Perot-like MIM(Metal-Insulator-Metal)structure has studied for holographic display device whose key component is composed of an aluminum sub-wavelength grating,and modulates phase of reflected light in the visible wavelength range has been studied.As is known,the commercialized Liquid Crystal on Silicon(LCOS)is one of the widely used spatial light modulator(SLM),but its phase modulation mechanism that is achieved by means of optical path difference in liquid crystal is not conducive to the device further reduced in order to achieve the required space bandwidth for the holographic display.We replace the top electrode layer of the LCOS with a sub-wavelength grating structure,although the geometry is similar to classical holographic display device but the physical theory is novel.When the incident light goes into the metal grating slit,a typical zero order and deep sub-wavelength Fabry-Perot resonance is strongly induced.The reflection phase of the edge of the cavity can be efficiently manipulated through MIM structure consisting of a thin intermediate dielectric medium layer,because the metal surface plasmon polariton are especially susceptible about the change of the ambient medium.Furthermore,to adapt to the future the demand of video holographic display,we investigate the possibility of dynamic real time modulation by changing the dielectric constant in the dielectric layer.Usually,aluminum is not considered as an attractive plasma material,but it is rich in resources,low cost and CMOS compatible,it is widely used in SLM devices,such as LCOS.Also,it is well-known that aluminum plasma characteristic is sensitive to the geometry of material.However,our sub-wavelength grating coupling structure effectively overcome the problems mentioned,the result of simulation has demonstrated that when the size of aluminum nanorod in aluminum grating changes from 140 nm to 190 nm,the results of phase modulation has little been influenced,even can be ignored,which providing robust possibly for fabrication.As the

关 键 词：全息显示 铝亚波长光栅 MIM FABRY-PEROT 

分 类 号：O4381[机械工程—光学工程]