研究超表面对光场的调控，对探索光与平面微结构相互作用的新物理、新效应和新应用具有重要意义。但如何对大角度范围的入射光实现宽频段和消色差高效率调控？其中包含的物理机制是什么？有什么限制条件？是目前急需解决的关键科学问题。本项目拟通过解析矩形金属光栅超表面沟槽中表面等离激元的局域模式与结构参数、入射角度、衍射特性的依赖关系，研究具有上述调控特性的超表面的物理机制，结构参数的选择范围及应用。利用FDTD等数值方法和电子束刻蚀等微纳加工技术，验证可见光波段的照明光在30-70度入射角范围、200nm带宽、具有90%以上衍射效率，以及10-80度入射角范围、三原色光无色差、整体效率50%以上的两种超表面及其在矢量、涡旋光场产生和无色差反射与聚焦等方面的应用。项目的完成，为进一步提高我们对超表面调控光场的物理机制的认识，掌握不同超表面的设计条件，拓展超表面在光学成像、全景显示等领域的广泛实用奠定基础。

To study the control of metasurfaces over light field is of great interest for searching for new physics, new phenomena, and new applications of interaction between light and planar microstructures. However, how to high efficiently control the incident light field in broadband and without chromatic aberration in wide range of angle, what is the physical mechanism and there are any limitations involved in the controlling, are currently key scientific problems to solve urgently. In this project, by analytically studying the dependence of excitation of local plasmonic modes in the grooves of rectangular metal grating-constructed metasurfaces on geometric parameters, incident angle, and diffraction characteristics of light, we will study the mechanism of metasurfaces in controlling light field with the above properties, know well the parameters range of constructing such metasurfaces, and search for their applications. Based upon numerical simulations such as FDTD method and fabrication technologies as e-beam lithography etc., we expect to demonstrate two kinds of metasurfaces in the visible: One is with 200nm band and higher than 90% efficiency as the incident light is from 30 to 70 degrees, the other is with chromatic aberration-free at three primary colors and over 50% total efficiency in the range of 10-80 degree angle, and then confirm their applications in producing focusing beam, vector beam, vortex light field, and achromatic reflection and focusing beams etc. The accomplishment of the project will further improve our knowledge on the physical mechanism of metasurfaces in controlling optical field, let us know well the parameter requirements of designing various metasurfaces, and establish solid foundation for applications of metasurfaces in wide fields such as optical imaging and panorama display etc.