共查询到20条相似文献,搜索用时 15 毫秒
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Xin Li Ruizhe Zhao Qunshuo Wei Guangzhou Geng Junjie Li Shuang Zhang Lingling Huang Yongtian Wang 《Advanced functional materials》2021,31(35):2103326
Metasurface holography is attracting increasing attention owing to its numerous advantages over conventional holography techniques, such as precise control of phase profiles, compact sizes, and multiple information channels via a single optical element. Metasurfaces provide a flexible platform for incorporating various multiplexing techniques. Inspired by code division multiplexing (CDM), which is widely employed in networking and wireless digital communications, metasurface holography for generating dynamic holographic images controlled by both the patterned beam profiles and polarization states is designed and realized in this study. Specifically, two orthogonal polarization states and 16 code bases of light illumination are combined to generate 32 independent channels. Only the correct code reference can decode the target image for a specific channel, providing encryption for information transportation. Meanwhile, the demonstrated metasurface holography with CDM can realize active modulation via a digital micromirror device. The proposed metasurface can be utilized to achieve dynamic information display, data storage, optical encryption, and other applications in optics. 相似文献
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合成孔径数字全息的记录、再现及实现 总被引:2,自引:0,他引:2
介绍了合成孔径数字全息记录和再现的基本原理,提出了相应的实现方法和技术方案。特别对合成孔径数字全息再现中的两类方法:用单参考光记录的子全息图数字再现光场复振幅叠加或强度叠加,以及用多参考光记录的子全息图数字再现光场复振幅叠加或强度叠加方法进行了详细理论分析和实验研究。结果表明,合成孔径技术是一种提高数字全息再现像的分辨率的有效方法。与传统的子全息图直接拼接的合成孔径数字全息再现方法相比,用子数字全息图再现光场复振幅叠加或强度叠加两种再现方法均可实现合成孔径数字全息的再现,并可显著提高再现像的分辨率,但强度叠加方法的记录和再现难度远小于前者。在实际中可以根据解决问题的要求和子数字全息图的记录情况选用。 相似文献
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提出了一种新的假彩色编码技术.对单个三维物体赋以同种颜色.不同物体不同的颜色,前后物体的遮蔽效果以不同的颜色加以体现.增强了立体感.并给出了实验结果. 相似文献
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报道了正交线偏光全息中的正交再现现象.所谓的正交再现,指的是衍射光的偏振态与记录信号光的偏振态是正交的.基于新发展的张量偏光全息理论,分析了正交再现的条件;搭建实验平台,在实验上观察到正交再现现象.通过定量分析与多组实验,可以得出当衍射光实现正交再现时,其功率大小与记录过程中信号光和参考光的干涉夹角有关.实验结果和理论... 相似文献
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Hai Xia Liu Yi Cen Li Fang Jie Cheng Xin Wang Ming Yang Chang Hao Xue Song Zhang Jia Qi Han Guan Xuan Li Long Li Tie Jun Cui 《Advanced functional materials》2024,34(2):2307806
A holographic tensor metasurface (HTM) is proposed from the energy perspective to achieve flexible regulations of polarization and energy distributions for simultaneous transmissions of power and information. A dual-polarization receiving metasurface with high isolation is also proposed to enable simultaneous receptions of power and information. Based on the two metasurfaces, a novel system for simultaneous wireless information and power transmissions (SWIPT) is established, which can transmit microwave powers and information signals by flexibly regulating the electromagnetic waves in different polarizations. The proposed HTM can generate non-diffraction Bessel beams of two polarizations to keep high-power transfer efficiency in an environment with obstacles. A rectifier circuit is designed with a wide dynamic range to integrate with the receiving metasurface to capture the strong powers and weak signals simultaneously. The effect of different modulations on the rectification efficiency of microwave-to-DC and the performance of the SWIPT system are analyzed. The SWIPT system is verified by experiments to realize simultaneous transmissions of information and powers by only using the metasurfaces, which is beneficial to integrate the wireless sensor networks, communication modules, and artificial intelligence algorithms to build up smart cities. 相似文献
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相位梯度超表面可在其表面形成额外的平行波矢分量,从而可对反射波的反射方向进行调控,导致反常反射现象。主要研究在垂直入射情况下通过反射超表面实现对电磁波的反常反射,首先阐明了反射超表面的设计原理,得到了反射超表面的设计理论,并设计了基于开口谐振环的反常反射超表面。仿真和测试结果表明,通过优化设计不同结构参数的开口谐振环阵列单元,可以在设计频点处通过超表面平行波矢控制电磁波的反射方向,将反射波偏折到设计方向。由于其对电磁波反射方向的自由调控,反射超表面在天线、隐身等领域具有重要的应用前景,可望应用于高方向性天线、雷达散射截面缩减、反射聚焦平板等。 相似文献
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合成全息图利用多视差图像实现立体显示,并可通过分区曝光实现大面积制作。介绍了数字合成全息的原理及其实验系统,针对其制作过程中的两种图像采样方式,研究了图像的分割和重组原则。通过对单元全息图合成拍摄中图像重叠投影的分析,基于非成像光学理论设计制作了能实现这一功能的透镜,并借助光学软件对其进行了仿真。最后利用所设计的透镜进行了合成全息实验,结果表明,利用所设计的重叠投影透镜和适当的图像处理方法,能合成出轮廓清晰、立体感强的全息立体图。 相似文献
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偏振全息术在光学时钟分布中的应用 总被引:2,自引:0,他引:2
提出了采用偏振全息术制做全息光学元件以实现光学时钟分布的方法。初步实验得到了可作为4输出时钟分布的全息光学元件,文中还提出了用偏振全息术获得多输出端时钟分布的方案。 相似文献
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Chen Xi Huang Jingjing Zhang Qiang Cheng Tie Jun Cui 《Advanced functional materials》2021,31(36):2103379
As an alternative to conventional wireless communication techniques that use amplitude, frequency, and phase modulations, polarization modulation (PoM) provides an additional degree of freedom for the modulation of carrier waves and allows the realization of simple transceiver designs. PoM also enhances physical-layer security in wireless communication systems owing to its vector-attribute and direction-dependence features. In this study, a prototype of PoM wireless communications based on a digital coding metasurface that can dynamically control the polarization of electromagnetic waves in a certain frequency band is demonstrated. The binary digital signals can be encoded on the optical rotation states of the circularly polarized beams through the real-time control of the bias voltages applied on the metasurface and successfully decoded at the receiving end. Because the metasurface is separated from the emitting antenna, the design can simplify the setup for multichannel communications and provide more flexibility by setting the emitting antennas at different operating frequencies at any time. 相似文献
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空间滤波合成狭缝彩虹全息术假彩色编码 总被引:1,自引:0,他引:1
采用空间滤波合成狭缝彩虹全息术对二维透射物进行假彩色编码。记录二维透射物的不同空间频谱所对应的物象时,参考光处于不同的传播方向,同时将透镜平移,全息图在白光再现时就出现不同颜色。 相似文献