Design of optical metasurfaces for innovative display devices

讲座名称：Design of optical metasurfaces for innovative display devices

讲座时间：2019-11-05 10:30:00

讲座地点：南校区G-240

讲座人：Boris Gralak

讲座人介绍：

B. Gralak于1997年毕业于法国高等理工学院， 2001年与2010年分别获得了Aix-Marseille大学的博士学位和HDR。B. Gralak目前是CNRS-马赛菲涅尔实验室的高级研究员（科研总监），担任EPSILON研究组负责人，菲涅尔实验室 “电磁学和超材料”研究组负责人，CNRS-GDR Ondes（http://gdr-ondes.cnrs.fr/）GT1“理论与数值建模”研究组负责人，中法国际光子研究网络CNRS的IRN PHOTONET（http://www.photonet.cnrs.fr/）法方代表。在国际同行评审期刊上发表55多篇论文。主要的科学贡献包括有光子晶体中负折射率的第一个数值证明[J. Opt. Soc.Am. A 17，1012（2000）]，第一个热发射扫描隧道显微镜的数值验证[Nature 444，740（2006）]，超材料吸收和色散特性分析[J. Math. Phys. 51, 052902 (2010); J. Math. Phys. 58, 071501 (2017)]，光学设备的设计：防反射光栅，不可逆设备，平板透镜，隐形地毯，用于过滤的光栅等。

讲座内容：

In this presentation, we report the modeling, the design and the fabrication of transparent and flat optical surfaces which may find applications such as innovative display devices. A finite element method is used to model metallic nanoparticle gratings and to design efficient filters with polarization dependent properties together with high transparency over the visible range [1]. The color of the reflected light is controlled by exploiting the plasmonic resonance frequency which is determined by the size of the nanoparticles [1, 2]. The transparency of the device is governed by the density of nanoparticles and then it can be improved by decreasing this density, i.e. by increasing the lattice constant of the grating array. In order to prevent the optical surface from diffraction when the distance between nanoparticles is large, it is proposed to consider random arrangements of nanoparticles with a given inter-particle average distance. This original idea allows the design of structures with low densities, i.e. with long average distance between nanoparticles, which are likely to present non-specular diffraction orders in visible range. The quality of the transparency, obtained thanks to these low densities of nanoparticles, offers the possibility to use the proposed flat optical surfaces as transparent display devices. These promising results pave the way for head-up-display systems and could find some innovative applications in the transport industry such as in the automotive or aeronautic sectors for displays.

主办单位：空间科学与技术学院