高强度激光薄膜的研制

 为提高激光薄膜的抗激光强度,实验研究了薄膜新材料、镀膜基体的表面粗糙度和洁净度,薄膜中的杂质污染,镀膜后的热处理,以及小光斑扫描激光预处理对薄膜的损耗和抗激光强度的影响。     

Experimental Study on Semiconductor Optical Amplifiers with Angled Facets

１ＩｎｔｒｏｄｕｃｔｉｏｎＳＯＡｗｉｌｂｅｏｎｅｏｆｔｈｅｋｅｙｃｏｍｐｏｎｅｎｔｓｉｎｔｈｅａｌｏｐｔｉｃａｌｎｅｔｗｏｒｋｉｎｔｈｅｆｕｔｕｒｅ．ＳＯＡｈａｓｍａｎｙｖｅｒｙｉｍｐｏｒｔａｎｔａｐｐｌｉｃａｔｉｏｎｓ,ｓｕｃｈａｓｗａｖｅｌｅｎ...     

古壁画、陶彩颜料的拉曼光谱分析

本文利用拉曼光谱对河南班村遗址出土的仰韶彩陶陶彩以及河北磁县湾漳东魏北齐大型壁画墓中的壁画颜料进行了分析,成功的测定出陶彩及壁画颜料的成分。这一研究工作表明,拉曼光谱作为现代技术非常适合于易损和不允许取样的珍贵艺术品颜料的无损分析     

Simulation of coating flows with slip effects

This work is concerned with the numerical prediction of wire coating flows. Both annular tube‐tooling and pressure‐tooling type extrusion–drag flows are investigated for viscous fluids. The effects of slip at die walls are analysed and free surfaces are computed. Flow conditions around the die exit are considered, contrasting imposition of no‐slip and various instances of slip models for die wall conditions. Numerical solutions are computed by means of a time marching Taylor–Galerkin/pressure–correction finite element scheme, that demonstrates how slip conditions on die walls mitigate stress singularities at the die exit. For pressure‐tooling and with appropriate handling of slip, reduction in shear rate at the die exit may be achieved. Maximum shear rates for tube‐tooling are about one quarter of those encountered in pressure‐tooling. Equivalently, extension rates peak at land entry, and tube‐tooling values are one third of those observed for pressure‐tooling. With slip and tube‐tooling, peak shear values at die exit may be almost completely eliminated. Nevertheless, in contrast to the pressure‐tooling scenario, this produces larger peak shear rates upstream within the land region than would otherwise be the case for no‐slip. Copyright © 2000 John Wiley & Sons, Ltd.     

NaY(WO4)2:Sm3+粉末的制备及荧光性能

以柠檬酸三钠为结合剂,采用水热法结合高温烧结两步法制备了一系列NaY_1-x(WO₄)₂:xSm³⁺(x=0、0.005、0.010、0.015、0.020、0.025、0.030)粉末。通过X射线衍射(XRD)、扫描电镜(SEM)、红外光谱(FT-IR)和荧光性能(PL)对粉末的相结构、形貌、成分以及发光性能进行了表征。研究结果表明,所合成粉末为NaY(WO₄)₂的纯相,属四方晶系白钨矿结构,其形貌为3D花形。在405 nm的光激发下,NaY(WO₄)₂:Sm³⁺粉末在600 nm处具有最高的荧光强度,对应于Sm³⁺的⁴G_5/2→⁶H_7/2磁偶极跃迁,观察到橙红光发射,且Sm³⁺最佳掺杂摩尔分数为0.015时,粉末显示出最强的荧光发射强度。     

Eu3+离子注入β-Ga2O3单晶的应力变化和发光性质研究

采用离子注入法制备了不同剂量的β-Ga₂O₃:Eu³⁺样品,并在空气中进行了退火处理,成功实现了Eu³⁺的光学激活。通过拉曼和X射线衍射表征了β-Ga₂O₃晶体随Eu³⁺注入剂量的应力变化趋势,发现随着Eu³⁺剂量的增加,晶格应力先增加后减少,并对其内在机理进行了分析。利用阴极荧光光谱对晶体的发光性质进行了表征,主要观察到峰值位于380 nm附近、宽的缺陷发光峰以及峰值位于591 nm、597 nm和613 nm的Eu³⁺发光峰。通过高斯拟合发现,该380 nm发光峰主要由360 nm、398 nm和442 nm三个子峰构成,分别与自陷激子和施主-受主对有关。此外,Eu³⁺发光峰位置与强度受到基质局域晶体场的影响。     

蓝色荧光粉Sr3LnM(PO4)3F:Eu2+的发光调控

采用高温固相法合成了一系列Eu²⁺激活的Sr₃LnM(PO₄)₃F(Ln=Gd, La, Y; M= Na, K)荧光粉,并通过X射线衍射、扫描电子显微镜、荧光光谱等对样品的物相结构、形貌和发光特性进行了表征及分析。结果表明:成功合成了Sr₃LnM(PO₄)₃F:Eu²⁺荧光粉,样品的粒径为2~10 μm。荧光粉在蓝光区具有强烈的发射,归属为发光中心Eu²⁺的4f⁶5d→4f⁷跃迁。当基质中的碱金属M由Na变成K时,Eu²⁺的发光颜色由淡蓝色变成深蓝色,色纯度大幅提高,有效地调控了Eu²⁺在氟磷灰石Sr₃LnM(PO₄)₃F中的发光,进而发现了一种通过改变第二层配位原子来调控Eu²⁺发光的策略。     

Superhydrophobic,antireflective, flexible hard coatings with mechanically ultra-resilient moth-eye structure for foldable displays

Biomimetic inspiration from the moth-eye structure has led to many studies combining nanoimprint lithography (NIL) to realize low cost and large area anti-reflection (AR) coatings. However, the scope of application is severely limited by poor mechanical performance due to the intrinsic properties of the coating materials and the nanosized patterns. In this work, we demonstrate a moth-eye structured epoxy-siloxane molecular hybrid (ME-ESMH) fabricated using single UV-based NIL (UV-NIL) on a colorless polyimide (CPI), to be utilized as a flexible cover window (FCW) for foldable displays. Low reflection, a superhydrophobicity and good inward foldability were achieved, together with excellent thermal and chemical resistance. Furthermore, in situ uniaxial compression tests revealed that the fabricated structure can be elastically deformed and nearly restored to its original shape even after a large degree of compression. Our findings provide an easy-to-integrate solution for flexible hard coatings with superhydrophobic and AR properties, applicable to foldable optoelectronics.     

有机发光二极管显示屏的喷墨打印研究与展望

近年来,有机发光二极管(OLED)被广泛应用于智能手机等中小尺寸显示屏,并逐步进入电视等大尺寸显示领域和照明市场。随着OLED平板显示新时代的到来,对显示屏的彩色化与图案化研究提出了更高要求。与传统真空蒸镀技术相比,喷墨打印技术更容易实现大面积器件的彩色化和复合功能材料的图案化,且工艺简单,成本低廉,并可进行柔性器件加工。本文综述了采用喷墨打印技术制备OLED显示屏的研究现状,并系统介绍了喷墨打印设备的发展历程,通过优化bank结构提高显示屏的分辨率,优化墨水配方及组成配比抑制喷墨液滴的“咖啡环”效应,从而提高显示器发光均匀性,最后对国内外该技术产业进行了概述与展望。     

双功能电极改善有机发光器件效率滚降的研究

针对磷光器件存在严重的效率滚降,进而制约有机电致发光器件的实用化进程的问题,提出采用超声喷涂Poly(3,4-ethylenedioxythiophene)Polystyrene Sulfonate(PEDOT:PSS)作为透明电极,制备了红、绿、蓝三色有机电致发光器件.利用超声喷涂工艺材料利用率高的特点,起绝缘作用的水溶性PSS分子链在PEDOT:PSS透明电极中得到保留,使该透明电极具有空穴缓冲作用.这种双功能性,提高了器件在高电流密度下的载流子平衡性,降低了红、绿、蓝三色发光层中的极化子浓度,改善了红、绿、蓝三色器件的效率滚降问题,从最高外量子效率所在亮度到10000cd/m^2的电流效率滚降分别仅为14.9%、12.4%和16.0%.该结果表明,双功能性电极的引入显著改善了有机电致发光器件中载流子平衡性,具有降低三基色器件效率滚降的普适性,对实现高亮度、高效率发光器件具有重要意义.