新颖材料器件为全息显示带来的新机遇 = Novel materials and devices bring new opportunities for holographic display

Abstract

三维显示是人类获取身临其境视觉信息的有效途径，其中全息技术能够提供人眼所需的全部深度信息，被认为是理想的三维显示方式.然而受目前显示器件的限制，如可刷新调制器件的时间-空间（时空）带宽积受限、海量数据云处理速率限制、图像质量不高的问题等，全息显示技术的发展进入了瓶颈期.为了提高显示质量、扩大时空带宽积、提升系统性能，需要发展崭新的全息显示器件，从根本上解决目前遇到的问题.超颖材料、超构表面以及二维材料等诸多新颖材料的涌现为全息显示带来新的机遇.超颖材料（表面）通过特殊设计，利用远小于波长的超构单元实现对波前各向同性或各向异性的振幅与相位的特异调控，进而将全息信息映射到超颖材料（表面）全息显示器件上，通过调控光波实现各种显示.发展可刷新的超构（表面、二维）材料并应用于动态全息显示中是未来的重要方向.虽然现有的新颖器件还面临着各种问题，但它们可为全息显示的发展提供潜在的可行性和新的视角与发展动力. Three-dimentional (3D) display is one of the effective ways to obtain visual information feeling like actual environment. Since holographic technique can provide full depth information for human eyes, it is considered to be an ideal 3D display technique. However, it is limited by the features of display elements and devices, such as the time-space (time and space) bandwidth product, massive data processing speed and low image quality and so on. To improve the display quality, expand the time-space bandwidth product, improve the performance of the system, and overcome the limitation, optical elements and devices made from novel materials are introduced, such as metamaterials, metasurfaces and two-dimensional (2D) materials, and thus bringing new challenges and opportunities to holographic display. Meta-atom structure whose unit size is much less than wavelength is designed and fabricated specially, and it can realize the isotropical or anisotropical manipulation of the amplitude and phase of the light wave. By encoding the meta-atom structures into the hologram, the 2D or 3D images can be achieved. The development of a refreshable metamaterials and their applications in dynamic holographic display will be one of the most important topics in the future. Though the 2D or 3D holographic displays based on the elements and devices made from novel materials still have some basic problems, it is expected that they would bring new impetus and promising perspective for the future display market.