Study On The Dynamic Holographic Display Technology Based On Metasurface

Holography based on metasurface(meta-holography)is considered as the one of most significant methods in 3D visualization technology currently.In recent years,microfabrication techniques are flourishing.In another way,as the phase modulations principle of metasurfaces continues to be developed,the metasurface has a great advantage in holographic coding with its excellent electromagnetic modulation capabilities and easy manufacturing characteristics.Therefore,the meta-holography has been a focus of research.Meanwhile,holographic principles have become a feasible method for designing plasma metasurface to excite free space beams or produce surface waves with specific field distribution.With the increasing maturity of static holographic technology,dynamic holographic display technology has drawn the worldwide attention of researchers,and holographic dynamic loading and real-time modulation have become important research directions.The metasurface exhibits high capacity,high resolution in encoding static holographic.However,once the metasurfaces are fabricated,most of them will remain static and non-tunable,and meta-holography is accompanied by some problems such as low frame rate and low refresh rate.This article is based on the research on the dynamic meta-holography,and the research content mainly includes:1.Beginning with the dynamic hologram based on the spatial channel multiplexing metasurface,the limited number of spatial channels can produce the intensive hologram frame,which can greatly expand the dynamic ability of traditional meta-holography.We propose a design of a super-pixel that consists of 8dynamic pixels,and the holographic image plane is constructed by some periodic super-pixels.This design further expands the display range of the dynamic meta-holographic device,and can freely expand the number of the super-pixel in need to accommodate more complex display scenarios.2.It is proposed a dynamic holographic design based on metasurfaces combining spatial channel multiplexing and polarization multiplexing.The spatial channel capacity of the design is improved significantly by the composite phase encoding method.Each spatial channel of the spatial channel meta-hologram device has a different response to the incident light polarization,and the dynamic pixel of each spatial channel exists in three different display states.For the spatial channel multiplexing metasurfaces with N spatial channels,its holographic frame is raised from 2~N to 3~N with the assistant of the polarization multiplexing method.The various combinations of the incident light polarization and the selection spatial channels not only increase the possibility of dynamic but also the privacy of the holographic display,making this design also applicable to the field of optical information encryption.