Design of Raman spectroscopy measurement system based on SHINERS

基于壳层隔绝纳米粒子增强技术,开发了一种新型的等离激元拉曼光谱测试系统,该系统能够有效地提高被测物质的拉曼反射信号强度。壳层隔绝纳米粒子增强技术采用包裹了极薄的二氧化硅或者氧化铝壳层的单层金纳米粒子,能够产生较强的表面增强效应。整个测试系统的硬件部分主要包括双处理器(ArM和dSP)主控板、半导体激光光源、光谱仪、光纤探头和粒子施加装置;软件部分能够自动获取被测物质的拉曼谱图。这里,粒子施加装置用于自动地将壳层隔绝纳米粒子施加到被测样本中。在实验中,将测试系统用于检测食品违禁添加物三聚氰胺和孔雀石绿,以验证壳层隔绝纳米粒子增强拉曼光谱技术。实验结果表明,该测试系统具有较高的测试灵敏度和较短的测试时间,广泛地适用于食品安全中痕量物质快速检测。In this paper,the Raman spectroscopy mea surement system was presented,where Shell isolated Nanoparticle Enhanced Raman Spectroscopy(SHINERS) technique was used to amplify the Raman signal.This technique used gold nanoparticles coated with a thin,uniform,fully enclosed and optically transparent shell of silica or alumina so that the gold core generated a large surface enhancement.Based on this technique,the hardware framework of this measurement system was mainly composed of double central control chips(ARM and DSP),a laser diode source,a spectrometer,a fiber probe and a nanoparticle giving device;and the software of this system can achieve the Raman spectrogram automatically.The giving device was used to spread the SHINERS particle into the samples for improving automation.The experiments were performed to detect the food added melamine and malachite green for verifying the effectiveness of SHINERS.The results show that the measurement system is of high detection sensitivity and short testing time effectively,which can be widely adopted in the rapid detection of trace substances in food safety.国家重大科学仪器设备开发专项(2011YQ03012417

Thermal performance testing for high power light-emitting diode based on voltage-current characteristics with pulse injection

热学特性是影响功率型lEd光学和电学特性的主要因素之一,设计了一套基于脉冲式u-I特性的功率型lEd热学特性测试系统,可以测试在不同结温下lEd工作电流与正向电压的关系,从而获得lEd的热学特性参数。该系统通过产生窄脉冲电流来驱动lEd,对其峰值时的电压电流进行采样,同时控制和采集lEd的热沉温度,从而获得不同温度下lEd的u-I特性曲线。与其他u-I测试系统相比,文中采用了窄脉冲(1μS)工作电流,lEd器件Pn结区处于发热与散热的交替过程,不会造成大的热积累,大大提高了测量精度。实验中,对某功率型lEd进行了测试,获得了该器件的电压、电流和结温特性曲线,并利用b样条建立该器件的u-I-T模型,进而实现了对其结温的实时在线检测。Thermal performance is one of the main factors which affect the optical and electrical performance of high power LED.The thermal performance testing system for high power LEDs based on voltage-current characteristics with pulse injection was designed in this paper, which can test the relationship between the operating current and forward voltage of LED under different junction temperatures, thereby obtaining LED thermal characteristics parameters.The system worked by generating a controlled narrow pulse current to drive the LED, and sampling the peaks of voltage and current of LEDs with LED heat sink temperature control and acquisition, thereby obtaining the voltage-current characteristic curve in different junction temperatures.Compared with other voltage-current testing systems, the designed system adapts the narrow pulse duty cycle(1 μs), so the PN junction of LED devices is always in the process of alternately heating and cooling, which can avoid large heat accumulation and greatly improve the accuracy of measurement.In the experiment, a power LED device was tested by the system and the voltage-current-temperature curve was obtained.Then the B-spline based U-I-T model of the LED was established, so the real-time online detection of LED device was achieved.国家自然科学基金(61102030

Study of Silicon-based Mid-infrared Subwavelength Planar Optical Lens

硅是现代半导体微电子科技的基石材料，同时也是一种重要的光学材料。特别是在中红外波段，由于其高折射率和高透射率的特点，在通信硅基光子学，中远红外成像等领域有着非常广泛的应用。硅基平面光学技术由成熟的半导体微电子工艺技术和微光学的交叉融合而产生，在其基础上发展了诸如波导，光子晶体，微环耦合器等一系列光学元件，微纳透镜是其中一个重要的分支。采用平面光学技术制备的新型微纳光学元件很好地对传统块体材料进行了替代，具有轻量化、阵列化、易于集成、便于大规模制造等优点，并大量应用在探测、显示、光伏等领域。然而目前对平面光学元件的基础研究还很不完善，在实际应用中也暴露了一些固有弱点，本文围绕平面微纳透镜元件，在...Silicon is the most critical material in modern semiconductor technology, and also an important optical material because of its high refractive index and high transmission, which can find wide applications in various fields such as silicon photonics, mid/far-infrared imaging. Silicon based planar optics gains its popularity with the interaction between mature semiconductor processing technology an...学位：工学博士院系专业：信息科学与技术学院_微电子学与固体电子学学号：2312013015427

中红外硅微透镜阵列的离焦效应（英文）

采用严格数值算法对中红外硅微透镜阵列进行了模拟,该微透镜阵列特征尺寸小于波长工作波长.研究发现该微透镜阵列存在一个显著的离焦效应,其离焦量达到0.4左右,超出了现有的传统理论模型预测范围.对微透镜阵列进行了制作和焦距测试,发现测试结果跟数值模拟基本吻合.微纳衍射光学集成系统中透镜离焦量是系统集成非常重要的一个参数,该研究结果为硅微透镜阵列和中红外探测器光学集成提供有效参考.Supported by Special Project on the Integration of Industry；Education and Research of Aviation Industry Corporation of China(CXY2011XD24)