A series of azobenzene functionalized poly（aryl ether） copolymers（azo-PAEs） containing azo moieties on pendants was prepared by direct copolymerization. The amount of azobenzene chromophores could be controlled by...A series of azobenzene functionalized poly（aryl ether） copolymers（azo-PAEs） containing azo moieties on pendants was prepared by direct copolymerization. The amount of azobenzene chromophores could be controlled by the feed ratio of azo-monomer. Their chemical structures and properties were characterized by means of infrared（IR） spectrometry, UV-Vis, hydrogen nuclear magnetic resonance（Ill NMR）, difference scanning calorimetry（DSC）, and thermogravimetric analysis（TGA）. The results suggest that azo-PAEs had high glass transition temperatures（Tgs） and good thermal stability. By exposing their spin-coated films to an interference pattern laser beam, azo-PAEs could be used for the fabrication of thermal stable surface relief gratings（SRGs）.展开更多
Augmented reality(AR)displays,as the next generation platform for spatial computing and digital twins,enable users to view digital images superimposed on real-world environment,fostering a deeper level of human-digita...Augmented reality(AR)displays,as the next generation platform for spatial computing and digital twins,enable users to view digital images superimposed on real-world environment,fostering a deeper level of human-digital interactions.However,as a critical element in an AR system,optical combiners face unprecedented challenges to match the exceptional performance requirements of human vision system while keeping the headset ultracompact and lightweight.After decades of extensive device and material research efforts,and heavy investment in manufacturing technologies,several promising waveguide combiners have been developed.In this review paper,we focus on the perspectives and challenges of optical waveguide combiners for AR displays.We will begin by introducing the basic device structures and operation principles of different AR architectures,and then delve into different waveguide combiners,including geometric and diffractive waveguide combiners.Some commonly used in-couplers and out-couplers,such as prisms,mirrors,surface relief gratings,volume holographic gratings,polarization volume gratings,and metasurface-based couplers,will be discussed,and their properties analyzed in detail.Additionally,we will explore recent advances in waveguide combiner design and modeling,such as exit pupil expansion,wide field of view,geometric architectures of waveguide couplers,full-color propagation,and brightness and color uniformity optimization.Finally,we will discuss the bottlenecks and future development trends in waveguide combiner technologies.The objective of this review is to provide a comprehensive overview of the current state of waveguide combiner technologies,analyze their pros and cons,and then present the future challenges of AR displays.展开更多
基金Supported by the National Natural Science Foundation of China（No.51103060）.
文摘A series of azobenzene functionalized poly（aryl ether） copolymers（azo-PAEs） containing azo moieties on pendants was prepared by direct copolymerization. The amount of azobenzene chromophores could be controlled by the feed ratio of azo-monomer. Their chemical structures and properties were characterized by means of infrared（IR） spectrometry, UV-Vis, hydrogen nuclear magnetic resonance（Ill NMR）, difference scanning calorimetry（DSC）, and thermogravimetric analysis（TGA）. The results suggest that azo-PAEs had high glass transition temperatures（Tgs） and good thermal stability. By exposing their spin-coated films to an interference pattern laser beam, azo-PAEs could be used for the fabrication of thermal stable surface relief gratings（SRGs）.
文摘Augmented reality(AR)displays,as the next generation platform for spatial computing and digital twins,enable users to view digital images superimposed on real-world environment,fostering a deeper level of human-digital interactions.However,as a critical element in an AR system,optical combiners face unprecedented challenges to match the exceptional performance requirements of human vision system while keeping the headset ultracompact and lightweight.After decades of extensive device and material research efforts,and heavy investment in manufacturing technologies,several promising waveguide combiners have been developed.In this review paper,we focus on the perspectives and challenges of optical waveguide combiners for AR displays.We will begin by introducing the basic device structures and operation principles of different AR architectures,and then delve into different waveguide combiners,including geometric and diffractive waveguide combiners.Some commonly used in-couplers and out-couplers,such as prisms,mirrors,surface relief gratings,volume holographic gratings,polarization volume gratings,and metasurface-based couplers,will be discussed,and their properties analyzed in detail.Additionally,we will explore recent advances in waveguide combiner design and modeling,such as exit pupil expansion,wide field of view,geometric architectures of waveguide couplers,full-color propagation,and brightness and color uniformity optimization.Finally,we will discuss the bottlenecks and future development trends in waveguide combiner technologies.The objective of this review is to provide a comprehensive overview of the current state of waveguide combiner technologies,analyze their pros and cons,and then present the future challenges of AR displays.
