核燃料元件直线度自动检测系统研究

结合核燃料元件的特点,建立核燃料元件直线度的动态测量模型,研制了核燃料元件直线度自动检测系统。该系统利用人一机交互界面对一根锆合金包壳管进行扫描,通过CCD光透过型激光传感器非接触测量包壳管中心轴线空间直线度的方法,实现了核燃料元件直线度的自动检测。该系统检测的分辨率达到0．001mm、检测精度为0．01mm、检测速度为3根／min,并具有数据实时显示、超差和安全报警等功能。实际测量结果表明：该系统安全、稳定、可靠。     

Design of Wireless Power Transfer with High Efficiency for Biomedical Implants

Wireless power transfer (WPT) technology is a popular choice for biomedical implant devices. The demands of higher efficiency and smaller implantation size are hard to compromise in previous studies. In the present work, an implantable magnetic coupling resonant WPT system integrated with a metasurface element working at 430 MHz is presented. Similar planar copper coil components for the transmitting and receiving structures are used to construct the primary system, and then the metasurface element is integrated to constitute the whole WPT system. The effects of the distances between the transmitting coil and skin surface, between the skin surface, and receiving coil are discussed. The results show that the efficiency will be enhanced by 38–50 dB integrating with the metasurface.     

A metasurface‐based broadband quasi nondispersive cross polarization converter for far infrared region

A broadband nondispersive cross polarization converter (CPC) structure using metasurface for far infrared region has been proposed in this article. The structure is transmittive in nature, which converts a linearly polarized incident wave to its mutually orthogonal linearly polarized wave over a band of frequency ranging from 10.25 to 22.7 THz maintaining a high polarization conversion ratio (PCR) of more than 0.95. The fractional bandwidth of 75.6% corresponding to the center frequency of PCR bandwidth having more than 0.9 PCR value has been realized. The structure is also studied for oblique incidences where it shows wide band polarization conversion up to 45° for both TE and TM polarized oblique incident waves. The electric field distributions at the top and bottom surfaces of the structure close to the center frequency of polarization conversion bandwidth indicate the orthogonal rotation of incident linearly polarized wave at the frequency of interest. For the given set of media interface a separate study on polarization conversion through Brewster angle concept has been carried out simultaneously. The structure exhibits high PCR by maintaining the compactness in thickness (~ λ/5) as well as periodicity (~ λ/3) compared to the existing reported ones.     

电焊护目诱导透射滤光片的研究

利用金属膜和介质膜组合的诱导透射滤光片具有高峰值透过率与宽截止区的特点,设 计了在紫外区和红外区截止,在可见光区有指定要求透过率的电焊护目镜。并通过工艺研究,成功地研制出了无需胶合保护的电焊护目镜滤光片,且成功消除了长波旁通带和短波漏带的影响,各种物理性能稳定。并对制备工艺和实验结果进行了分析及论。     

Dielectric Metalens by Multilayer Nanoimprint Lithography and Solution Phase Epitaxy

Metasurfaces have ushered in a huge development for their superior ability in manipulating light properties including phase, amplitude, and polarization, which show great potential as alternatives for the refractive optical devices. Recently, many applications of metasurface including metalens have been proposed and investigated, aiming at substituting their refractive counterparts. However, the commonly used fabrication approaches employ electron-beam lithography (EBL) followed by dry etching or atomic layer deposition (ALD) of dielectric materials, which are expensive and inefficient. Besides, dry etching of dielectric materials at sub-100 nm scale with a high aspect ratio is challenging. Herein, a new approach for dielectric metalens fabrication is presented, which combines multilayer nanoimprint lithography and solution phase epitaxy. High aspect ratio ZnO nanopillars with a height-to-diameter ratio of over 7:1 are demonstrated. By using the multilayer nanoimprint lithography, increased aspect ratio nanostructures from shallow imprinting molds are obtained. The highly anisotropic growth characteristic enables nanopillars to grow at a height that exceeds the resist thickness. With this ability, ZnO metalenses are fabricated where the height of nanopillar reaches 1.1 μm, achieving a focusing efficiency of 50%. The process is cost-effective with a high throughput, which can be widely used for many optical applications.     

Development of “Advanced TFT‐LCD” with good legibility under any ambient light intensity

A new LCD referred to as an “Advanced TFT‐LCD” has been developed. It consists of both transmissive and reflective electrodes in every pixel. Its subjective legibility and characteristics, such as contrast ratio, color gamut, and luminance, have been investigated at several ambient illumination intensities. As a result, it was confirmed that Advanced TFT‐LCDs offer better legibility than transmissive LCDs under any ambient illumination intensity.     

一种双分裂环结构的线-圆和线-交叉极化转换器

文中提出了一种高效、多功能的超表面极化转换器,该转换器由双分裂环谐振器周期阵列构成并置于F4B-2介电基板上。通过双分裂环谐振器的耦合效应可以有效拓展工作带宽。采用有限积分法对其极化特性进行分析。仿真结果表明：在5.5～8.55 GHz的频带(相对带宽为43.4%),实现了线极化到圆极化的转换,其能量转换效率优于99.5%;在10.31～15.31 GHz的频带(相对带宽为39%),实现了线极化到其交叉极化的转换,其极化转换比大于0.99。实验上,制备了样品并测试了其极化转换特性,实验结果与仿真结果基本吻合,验证了该转换器设计的合理性和有效性。所提出的超表面具有高效率、大工作带宽、多功能的特点,可应用于无线通信和极化操控设备。     

Double‐faced TFT‐LCD having one LC panel and one lighting system

Abstract— We have developed a novel liquid‐crystal‐display (LCD) system referred to as a “Double‐Faced LCD.” It has only one LC panel and one lighting system, but it works not only as a transmissive‐type LCD from one side but also as a reflective‐type LCD from the other side. Therefore, the thickness and the weight of the Double‐Faced LCD can be reduced compared to those of conventional LC modules that have two LC panels and two lighting systems.     

基于超表面的卫星天线设计进展综述

超表面是由亚波长尺寸单元密集排布组成的平面结构,具有强大的电磁波调控能力,而基于超表面的新型卫星天线在缓解业务多样化和用户数量激增方面极具潜力。介绍了目前卫星天线发展现状趋势,对传统天线加载超表面和单一超表面天线加以区分,归纳了加载超表面后天线所具有的低剖面、多极化、波束控制等优势,综述了超表面作为主要辐射元件的天线设计。分析了超表面在不同天线设计方案中的工作原理、效能以及存在的优势与不足,最后讨论了超表面卫星天线的发展方向,指出超表面技术在卫星天线设计领域中具有实用价值。     

电磁偏谐振阻抗匹配宽带传输超表面设计

针对传统传输超表面固有高Q值导致的工作频带窄的问题,提出了一种电、磁双模偏谐振阻抗匹配实现宽带传输超表面设计方法。建立了实现低损耗透波阻抗匹配的本征参数模型,并根据经典Drude-Lorentz模型分析了本征参数在电磁谐振与偏谐振区域的电磁特性。基于此,通过独立激励电、磁偏谐振模式,设计了满足宽频带阻抗匹配的本征参数电路模型。基于该模型,通过在超表面中引入金属微带线和平行贴片分别作为电、磁偏谐振器,调控结构的本征参数,从而在宽频带内实现所需本征参数条件。仿真和测试结果均证明,设计的超表面实现了双极化模式相对带宽为79.5%的3 dB传输带宽,且结构具有0°~40°的斜入射稳定性。该超表面具有超宽带、结构简单的特点,可应用于高性能天线罩设计中。