1 南京邮电大学 集成电路科学与工程学院, 南京 210003
2 南京邮电大学 射频集成与微组装技术国家地方联合工程实验室, 南京 210003
随着制造工艺的不断演进、电路规模的不断增大, 集成电路逐渐进入后摩尔时代。如何准确快速地进行寄生电容参数提取, 对于保证设计质量、减少成本和缩短设计周期变得越来越重要。文章提出了一种基于分段预留法的二维电容提取技术, 该技术基于改进的有限差分法, 采用非均匀网格划分和求解不对称系数矩阵方程, 模拟互连结构横截面, 可以高效计算出主导体的单位长度总电容以及主导体和相邻导体之间的单位长度耦和电容。为了验证提出方法的准确性和有效性, 进行了一系列验证实验。实验结果表明, 提出的互连线二维电容提取技术在寄生电容计算精度上平均提高了140倍, 运行时间平均缩了10%。
有限差分法 不对称系数矩阵 分段预留 寄生电容 FDM asymmetric coefficient matrix segment reservation parasitic capacitance
北京航空航天大学仪器科学与光电工程学院，北京 100191
随着光子材料和光子器件在可穿戴技术、智慧医疗、仿生机器人等新兴应用领域的不断拓展，研制具有优异机械柔韧性、生物相容性甚至生物可降解性的光子器件日益重要。为同时实现优异的光学性能和生物力学性能，柔性光子器件从材料合成、结构设计、功能实现到工艺制备等诸多方面亟需探索。其中，有机聚合物因其质地轻柔、生物相容性好、合成可控、结构功能易于改性等优势，被认为是制备柔性光子器件最具竞争力的材料之一。一系列新型的功能性有机光子器件，如光波导、衍射光栅、光子晶体等被相继被报道。本文综述了近年来柔性有机聚合物光子器件的研究进展，总结和分析了现有技术、方法和应用，并对未来的挑战和前景进行了讨论和展望。
激光与光电子学进展
2023, 60(13): 1316002
1 中国电子科技集团公司第三十八研究所，安徽 合肥 230088
2 孔径阵列与空间应用安徽省重点实验室，安徽 合肥 230088
3 中国人民解放军93209部队
为了实现全天时、高分辨率三维成像探测，文中提出了一种工作波长为1064 nm的光子计数激光雷达系统。其中，光学系统采用全光纤结构，增强了系统稳定性。雷达通过整机扫描方式对远距离目标进行成像探测，扩大扫描视场，水平方向达到360°，俯仰方向达到±30°，同时避免了由摆镜扫描引起的几何畸变；结合亚像素扫描方法，提高空间分辨率。最后通过自适应噪声阈值的多距离重建算法实现了目标的三维重建。实验结果表明，此系统在白天成功实现了3.1 km以外目标的三维重建，重建图像目标特征清晰，距离精度为0.11 m，空间分辨率为0.11 m，超过光学系统衍射极限。
激光雷达 光子计数 三维成像 全光纤 高分辨率 Lidar photon-counting 3D imaging all-fiber high-resolution 红外与激光工程
2021, 50(7): 20210162
Author Affiliations
Abstract
1 Telecommunications Laboratory (LABTEL), Graduate Program in Electrical Engineering, Federal University of Espírito Santo, Vitória-ES 29075-910, Brazil
2 School of Instrumentation and Optoelectronic Engineering, Beihang University, Beijing 100191, China
3 Center for Cognition and Neuroergonomics, State Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University, Zhuhai 519087, China
4 Physics Department & I3N, Universidade de Aveiro, Campus Universitário de Santiago, Aveiro 3810-193, Portugal
5 e-mail: leal-junior.arnaldo@ieee.org
Chronic wounds affect around 2% of the world population with an annual multi-billion dollar cost to the healthcare system. This background pushes the development of new therapies and procedures for wound healing and its assessment. Among them, the potential of hydrogen (pH) assessment is an important indicator of the wound healing stage and condition. This paper presents the development of the first optical fiber-embedded smart wound dressing for pH assessment. An intrinsically pH-sensitive optical fiber is fabricated using a polydimethylsiloxane (PDMS) precursor doped with rhodamine B dye. Raman and Fourier transform infrared (FTIR) spectroscopies are performed in order to verify the presence of rhodamine B and PDMS in the fiber samples. Then, the fiber is embedded in gauze fabric and hydrocolloid wound dressing. In addition, such low Young’s modulus of PDMS fiber enables its use as a highly sensitive pressure sensor, where the results show that the fiber-embedded bandage can measure pressures as low as 0.1 kPa with a high linearity in the range of 0 to 0.3 kPa. The smart bandage is subjected to different pH, which resulted in a wavelength shift of 0.67 nm/pH when the absorption peak at 515 nm was analyzed. Furthermore, pH increase leads to linear decrease of the transmitted optical power ( of 0.998), with rise and fall times below 20 s and 30 s, respectively. Therefore, the proposed optical fiber-embedded smart bandage enables the simultaneous assessment of pressure and pH on the wound region.
Photonics Research
2021, 9(3): 03000272
Author Affiliations
Abstract
1 State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates, South China University of Technology, Guangzhou 510640, China
2 Department of Chemistry, The Hong Kong University of Science & Technology, Clear Water Bay, Kowloon Hong Kong, China
Since the first report of aggregation-induced emission (AIE) concept in 2001, it has received intense attentions from academy and industry because of its important applications in diverse research fronts. Up to now, the luminogens with AIE property (AIEgens) have been widely used in optoelectronic devices, fluorescent bioprobes and chemosensors, and researchers have also committed to exploring the potentials of AIEgens in other cross-cutting areas. The AIEgens have shown superior advantages such as highly efficient emissions in the aggregated state and thus exhibited better performances in comparison with traditional luminescent materials whose emissions are usually quenched upon aggregate formation. In view of the significant achievements of AIEgens in recent years, this review presents representative advancements of AIEgens for the applications in organic optoelectronic devices, mainly including organic light-emitting diodes (OLEDs), circularly polarized luminescence (CPL) devices, electrofluorochromic (EFC) devices, luminescent solar concentrators (LSCs), and liquid crystal displays (LCDs). Not only the design strategies of AIEgens for these optoelectronic devices are analyzed, but also their structure-property relationship and working mechanism are elucidated. It is foreseeable that robust AIEgens with specific functionalities will find more and more applications in various research fields and play an increasingly important role in high-tech devices.
Author Affiliations
Abstract
1 State Key Laboratory of Precision Measurement Technology and Instruments, Department of Precision Instrument, Tsinghua University, Beijing 100084, China
2 e-mail: guojj018@tsinghua.edu.cn
Dopamine (DA), as a neurotransmitter in human brain, plays a crucial role in reward motivation and motor control. An improper level of DA can be associated with neurological disorders such as schizophrenia and Parkinson’s disease. To quantify DA, optical DA sensors have emerged as an attractive platform due to their capability of high-precision and label-free measurement, and immunity to electromagnetic interference. However, the lack of selectivity, limited biocompatibility, and complex fabrication processes are challenges that hinder their clinical applications. Here, we report a soft and biocompatible luminescent hydrogel optical sensor capable of recognizing and quantifying DA with a simple and compact interrogation setup. The sensor is made of a hydrogel optical fiber (HOF) incorporated with upconversion nanoparticles (UCNPs). DA molecules are detected through the luminescence energy transfer (LET) between the UCNPs and the oxidation products of DA, while the light-guiding HOF enables both excitation and emission collection of the UCNPs. The hydrogel sensor provides an optical readout that shows a linear response up to 200 μmol/L with a detection limit as low as 83.6 nmol/L. Our results show that the UCNP-based hydrogel sensor holds great promise of serving as a soft and biocompatible probe for monitoring DA in situ.
Photonics Research
2020, 8(11): 11001800
红外与激光工程
2020, 49(3): 0305007
1 中国科学院太阳活动重点实验室, 北京100012
2 中国科学院国家天文台, 北京100012
3 中国科学院国家空间科学中心, 北京 100190
4 中国科学院云南天文台, 云南 昆明 650500
平场改正可以扣除日冕仪成像过程中的不均匀性, 是其数据定标的必要步骤。提出一套基于乳白玻璃测量日冕仪平场的装置和方法, 并开展了相关模拟和实地测量以验证该方法的可行性。首先, 模拟了太阳经乳白玻璃后在日冕仪观测视场内扩散光源的均匀性, 模拟结果表明其均匀度为99.98%, 十分接近理想的均匀面光源。其次, 测量了12 cm地基日冕仪的平场, 测量结果显示该方法可以测量出日冕仪成像的不均匀性, 如探测器的条纹。平场改正后的结果符合日冕和天空背景亮度的径向分布。最后, 为评价利用乳白玻璃测量平场的有效性, 将其和天空平场进行了对比, 二者相关系数为99.94%, 线性拟合斜率为1, 具有极强的相关性。
光学器件 扩散片 日冕仪 图像分析 平场 光度测量
东南大学 电子科学与工程学院, 南京 210096
研究了采用双面体全息光栅作为波导入耦合器提高全息波导系统耦合亮度的可能性。通过优化双面体全息光栅的结构参数, 提高了系统对红、绿、蓝光的相对入耦合亮度。仿真结果表明, 当双面体光栅的厚度均为10 μm, 倾斜角偏差为±0.4°时, 系统的红、绿、蓝光的相对入耦合亮度对比只用单片光栅时分别提高了61%、60%、58%。
体全息光栅 波导 全息显示 volume holographic grating waveguide holographic display
条纹计数法解调精度受限，而常用的高精度外差调频解调法(如相位生成载波法、线性调频法)，在光源调频过程中伴生有幅度调制并且调制解调系统复杂。提出了一种基于双光纤光路相位解调的法布里珀罗(F-P)位移传感器，原理上省去了光源调频过程，在提高检测精度的同时，成本与条纹计数法相当。与已有报道的双光路结构不同的是，该传感器对两干涉光路之间相位差无严格要求，安装调节简单，降低了传感器的工艺难度。位移测量实验结果表明，该传感器在0～500 μm的测量范围内，线性度为1.1%，误差限值为±3 μm。
传感器 光纤位移传感器 双光纤法布里珀罗干涉仪 直接相位解调 条纹计数法
