This paper describes a composite control approach that improves the accuracy and dynamic performance of the control of a voice-coil-driven, two-dimensional fast steering mirror (FSM). Strong nonlinearity, perturbation of parameters, unmodeled dynamics and external disturbances typically compromise the performance of the FSM. The proposed controller combines a tracking differentiator (TD), linear extended state observer (LESO), and a double-integral global fast terminal-sliding mode control (DIGFTSMC). The TD corrects the reference command signal, and the LESO approximates and counteracts system disturbances. The sliding surface is then equipped with the double-integral operators and an improved adaptive reaching law (IARL) to enhance tracking accuracy, response speed and robustness. Prior to physical experiments, systematic numerical simulations were conducted for five control algorithms across four typical test scenarios, verifying the proposed controller's feasibility and preliminary performance advantages. It is found through experimentation that the proposed controller lowers the time esterified by the step response adjustment by 81.0% and 48.4% more than the PID controller and the DIGFTSMC approach with no IARL, respectively, and the proposed controller enhances error control when tracking sinuoidal signals and multisinusoidal signals. Simulation results consistently align with experimental trends, confirming the proposed controller's superior convergence speed, tracking precision, and disturbance rejection capability. Furthermore, it cuts the angular movement swing by an average of over 44% through dismissing needless vibration interruptions as compared to other sliding mode control techniques. Experimental results demonstrate that the proposed composite control approach significantly enhances the disturbance rejection, control accuracy, and dynamic tracking performance of the voice-coil-driven FSM system.

A stable and efficient composite electrochromic material, Vanadium Pentoxide combined with polyethylene oxide (V2O5-PEO), was exhibited using an Electrophoretic Deposition (EPD) technique. The interlayer spacing of V2O5 was adjusted by the PEO component during electrophoretic adsorption, allowing for rapid ion exchange, with overall conductivity being enhanced and electrolyte penetration being accelerated. The elemental composition of the films was analyzed via X-ray Photoelectron Spectroscopy (XPS). A higher relative content of V4+ was observed in the green and blue states, while V5+ was predominant in the orange state. An electrochromic device (ECD) was assembled using V2O5-PEO as the active electrochromic layer. Multicolor performance was demonstrated by the device, with transitions observed between yellow, yellow-green, green, blue-green, orange, and various intermediate shades. Due to the moderate increase in the interlayer spacing of the film, the ionic migration ability was enhanced, with a balance achieved between the conductivity and ion exchange capability of PEO. Outstanding electrochromic performance was exhibited by the V2O5-0.5PEO device, including a rapid response time (3 s for coloration and 1.5 s for bleaching at 796 nm), high optical contrast (Delta T = 40 % at 796 nm), and a significant coloration efficiency (CE = 38.3 cm2/C).

In this study, we develop a simple method for efficiently preparing poly(2,2 '-bithiophene) flexible electrochromic devices. The poly(2,2 '-bithiophene) films are fabricated in the ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate. The poly(2,2 '-bithiophene) films are characterized by Fourier transform infrared spectroscopy, scanning electron microscope, and ultraviolet-visible absorbance spectroscopy. The poly(2,2 '-bithiophene) films exhibit electrochromic behavior, transitioning from an orange-red color in its reduced state to a dark green upon oxidation, particularly pronounced in the near-infrared region. Further studies demonstrate that poly(2,2 '-bithiophene) films exhibits flexibility, allowing it to be bent and folded. This method for fabricating poly(2,2 '-bithiophene) films shows promising potential for future applications.

A vanadium oxide (VO) film was prepared on indium tin oxide (ITO) glass using a simple electrophoretic method and the VO film and its device demonstrated multicolor electrochromic properties of yellow, green, orange-red, and their intermediate colors. The X-ray diffraction (XRD) and X-ray photoelectron spectra (XPS) were employed to characterize the composition of the as-prepared films. The ratio of V5+/V4+ in the XPS is significantly different in the yellow, green, and orange-red states and this ratio can be adjusted by applied voltages. The detailed effect of calcination temperature as a post-treatment method on the electrochromic performance of VO film was explored. With the increase of calcination temperature, the optical modulation ability of the films was enhanced, and the color change contrast of the films was most obvious at 200 degrees C. Meanwhile, the cyclic stability of the VO films was also enhanced. The cyclic voltammetry (CV) curves show that the prepared V2O5 films have high cyclic stability at a calcination temperature of 300 degrees C. The color efficiency (CE) values of the VO devices were 3.4 cm2C-1 (from initial yellow to green) and 21.6 cm2C-1 (from green to orange-red) at 700 nm, and the coloring time (Tc) and bleaching time (Tb) of the VO devices were 6 s and 10 s, respectively. This work develops a simple and environmentally friendly method to prepare VO films and their devices with multicolor electrochromic properties. (c) 2024 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement

针对单帧复杂背景红外图像点目标检测算法存在复杂背景下处理效果不理想、处理时间长的问题,提出了一种层次卷积滤波检测算法。主要分为两个部分:第一,根据红外小目标特性,设计一种层次卷积滤波的算子,对图像进行滤波处理,实现图像中小目标的增效和背景抑制的效果;第二,采用基于最大值的自适应阈值方法,对图像进行二值化操作,过滤背景杂波,最终提取到待检测的目标。在大量不同背景红外图像中进行实验,论文算法在背景抑制因子和信噪比增益的性能量化结果上优于现有5种典型红外弱小目标检测算法的性能结果,且平均处理时间仅为高斯拉普拉斯(Laplacian of Gaussian,LoG)滤波算法的30.42%。通过实验对比,表明该层次卷积滤波算法可以有效解决在不同复杂背景下的红外图像中对小目标检测的问题。

为了实现结构紧凑高效的快速反射镜,对磁阻式电磁驱动进行研究.先对磁阻式电磁驱动的工作原理、结构组成、理论模型进行详细分析,然后采用有限元方法分析计算了永磁体、线圈、气隙等尺寸参数对驱动力矩的影响,最后设计、制作了磁阻式快速反射镜样机并进行测试,结果表明:快速反射镜外形尺寸为Φ32 mm×38 mm,行程大于±1°,X、Y轴的阶跃响应上升时间分别为15.9 ms和13.5 ms,带宽大于400 Hz.研究结果有助于掌握磁阻式电磁驱动的特性,由此设计的快速反射镜具有低功耗和结构紧凑的特点,适合在空间激光通信等领域应用.

In recent years, Fabry-Perot (F-P) cavity-type electrochromic devices composed of more stable inorganic materials have been extensively investigated for achieving colorful reflective displays and military camouflage functions. However, the majority of reported substrates for colorful F-P cavity electrochromic devices are rigid conductive glasses, which hinders their practical application in flexible reflective displays and camouflage. Herein, we construct a WO3/W/Au bilayer F-P cavity multicolor tunable electrochromic device based on a flexible porous filter membrane, in which WO3, an inorganic electrochromic material, is used as the electrochromic layer, metallic W as the partial reflective layer, and metallic Au as the total reflective and conductive layer. Highly flexible bilayer F-P cavity multicolor electrochromic devices have been prepared by combining UVcurable electrolytes and thermoplastic sealing procedures. By adjusting the thickness of the WO3 layer, a wide spectrum of colors including yellow, purplish red, violet, blue, green, olivine, peach, etc. can be obtained. In addition, by adjusting the driving voltage of the electrochromic device, more precise color adjustment can be achieved. The electrochromic device has a fast coloring (2.06 s) and bleaching (2.70 s) response time, providing a new solution for future flexible colorful reflective display devices.

To improve the dynamic response characteristics of an opto-electronic fine tracking system based on VCA （voice coil actuator） fast steering mirror （FSM）， a pre-amending method is studied and implemented to the FSM execute component. A feedforward adjusting step is additionally applied for optimizing the control of the FSM according to the target position variation obtained by a target detection and recognition component. The configuration and principle of the opto-electronic fine tracking system based on FSM are described， and the control of the VCA driven fast-steering mirror is modeled. Further， the feedforward-feedback control method is implemented. An experimental system， consisting of a target simulation part， target imaging and detection part and a target tracking part， is constructed to test and verify the method. The delay of the system is shortened from 2.9ms to 0.8ms， and the dynamic response bandwidth is improved from 20Hz to 45 Hz， indicating that the pre-amending control method can significantly reduce the phase lag of the opto-electronic fine tracking system and improve the systematic response characteristic.

不同粗糙表面反射偏振特性的明显差异为目标探测与识别奠定了基础,其研究受到不同领域的广泛重视.基于粗糙表面反射原理和反射偏振理论模型,对粗糙表面反射偏振特性的研究进展进行了深入且详尽的归纳与总结.对粗糙表面反射光偏振特性与入射角度、入射光波长、表面粗糙度等属性之间的关系进行了对比分析,并在此基础上对粗糙表面反射偏振特性的应用前景作出了阐述.最后,针对粗糙表面反射偏振研究目前存在的问题与未来发展给出了思考.

为了提高数字式光谱仪的测量效率,研究并实现一种基于FPGA+ARM架构和两级数据缓存的嵌入式高速数据采集与处理技术.采用FPGA为高速A/D转换器提供采样时钟,采样数据由FIFO进行一级缓存,实现跨时钟域的数据传输.采用ARM外围设置的动态数据随机存储器(DDR3)完成二级缓存,解决由于数据实时处理相对偏慢所造成的数据传输堵塞、丢失等问题.实验测试表明数据传输稳定可靠,采集速率可达65 MHz,传输速率最高可达25.6 Mbytes/s,归一化光谱强度误差小于0.5％.可推广应用于具有大吞吐量嵌入式数据采集与实时计算处理需求的精密仪器与设备.

多波长辐射测温是非接触测温的重要方法,针对辐射测温发射率难以确定,从而导致测量误差较大的问题,提出了随波长和温度改变的变发射率模型,结合最小二乘法设计了辐射测温算法,并采用近红外光纤光谱仪对高温炉的辐射进行了测量.通过测量和标定,该算法在1 073 K～1 273 K的温度下进行实验,最终得出该算法的误差在约1 100nm～1 600 nm范围内误差不高于1.60％,具有较高的测量精度和测量速度.

为解决光电跟踪仪跟踪精度测量过程中光束大范围指向的模拟问题,设计了一种大口径、高精度二维快速控制反射镜(fast steering mirror, FSM)。采用微晶材料设计了长、短轴分别为230 mm和160 mm的椭圆形平面反射镜,面形精度优于λ/30。采用音圈电机驱动,通过柔性支撑铰链设计及DSP嵌入式控制系统,运动行程达到±30 mrad,运动控制精度达到5 μrad,运动控制线性度优于±0.20%,角分辨率优于1 μrad。通过软件控制,实现对入射光束圆形轨迹运动、直线轨迹运动、随机运动等形式的运动模拟。最后,对设计指标进行实际测试,可以满足跟踪精度光束动态模拟的测试需求。

为了解决非接触测温系统中常见的成本高昂、系统复杂、实用性差、响应速度慢等问题,采用多光谱测温和快速响应光电探测技术,设计了一套低成本高速多光谱辐射测温系统.利用高速微弱光信号采集模块、高速模数转换芯片、高性能可编程门阵列和同步动态随机存取内存保证了微弱光信号的高速转换、同步采集、大容量缓存,具备纳秒级变化温度场的测量能力.结果表明,测温误差小于±1％,时间分辨率可达到50ns.这一结果对于快速变化温度场的测量是有帮助的.

为了提高精密指向组件的控制参数整定效率,采用改进型继电反馈自整定方法,实现其PID参数的自动整定.建立典型精密指向组件的数学模型,推导传递函数,并采用Matlab进行计算分析.在光学平台上搭建实验测试系统,进行精密指向组件PID参数的改进型继电反馈自整定控制实验,获取临界增益Ku和临界周期Tu,根据整定公式得到PID参数,并与理论计算结果进行比对.测试结果表明:改进型继电反馈自整定过程可以获取优化的参数,具有超调小、响应速度快等优点.

The mirror in the high-energy laser beam combining system needs to be adjusted quickly and accurately before working. A two-dimensional electronically controlled adjustment mirror is designed. The main body of system adopts an integrated flexible support design. The drive adopts a stepping motor and a deceleration mechanism to drive the screw. The precise measurement of the mirror deflection angle adopts an eddy current sensor and DSP is used as main Control module. The working principle and design of system is analyzed, which conducts in-depth research on the system calibration method and control algorithm. In order to meet the requirements of system adjustment speed, the S-shaped acceleration and deceleration algorithm is applied as the control algorithm of adjustment mirror. A piecewise linear system calibration method is adopted. The system has been tested experimentally, and experimental results show that within the range of ±500″, the in-position time is within 3s, and the control error is less than 2″, which can meet the system requirements.

量子点分立的能级结构使其具有独特的光电性质,因而在激光能源、光电检测等领域应用广泛.其尺寸调谐的受激辐射特性与灵活多变的应用形态也使其成为一种理想的荧光标记材料,在生物医学、微观物质检测以及防伪与目标识别等领域备受关注.对于应用场景多为宏观自然环境的防伪与目标识别领域,不可避免地需要对红外波段的量子点荧光进行较远距离的检测与分析.因此,文中基于微弱信号检测技术设计构建了一套红外量子点荧光的远距离探测系统,并用其对PbS胶质量子点薄膜荧光进行了检测实验.实验结果及分析表明,波长～13 00 nm的红外量子点荧光辐射可以在100～200 m距离之外被系统有效提取,从而实现红外量子点材料的远距离识别.系统对荧光特性的检测结果用于分析和指导不同红外量子点材料的制备过程,也将推动其远距离识别应用的多样性发展.

为获取大行程精密钢带夹轮传动系统的传动特性,以一维精密气浮导轨为载体,钢带夹轮传动机构作为传动装置,采用三环PID控制算法,设计并搭建测试平台.参照JJF 1251-2010的校准标准,对钢带传动特性进行测试.测试结果表明,在钢带所受的压力和拉力满足一定阈值的条件下,钢带传动系统的定位精度随钢带所受拉力的增加而提高,与所受压力无关;速度稳定性不受钢带所受压力和拉力的影响.测试结果为三坐标测量机等精密仪器的传动系统设计提供了有益的参考.

快反镜通过精确控制反射镜偏转方向从而精确控制光束偏转角度,由于其具有响应速度快、工作带宽高、指向精度高等优点,被广泛应用于激光武器、精密跟踪、自由空间光通信等领域,实现精密跟踪、稳瞄、稳像、扫描和像移补偿等功能.介绍了国内外公司和研究机构研制的音圈电机快反镜的现状,分析了音圈电机快反镜的组成,对反射镜、驱动器、转角测量模块、柔性支撑等组件的方案选型进行了讨论.介绍了所研制的音圈电机快反镜的性能.最后,讨论了音圈电机快反镜大口径、高工作带宽、大转角范围和高指向精度的未来发展方向.

胶质红外量子点优异的光学性能使其荧光特性具有广泛的应用前景,在实际应用中通常需要封装成薄膜形态以保持稳定的荧光特性.然而,分散形式的改变可能会导致量子点荧光效率降低以及荧光角度特性变化.因此,建立了红外量子点荧光强度探测系统,对胶质红外量子点薄膜在不同角度激发光入射时产生的荧光分布情况进行研究.实验及分析结果表明,激发光与样品表面夹角大小在10°～170°之间的较大范围内入射时,在反射及透射荧光区域均可探测到荧光峰值强度70％～80％以上的荧光出射,在这一范围内的反射荧光与透射荧光强度差异和荧光强度随激发光入射角度的变化规律分别与样品中量子点的浓度以及分布形态有关.同时,随着入射激光能量的增强,样品出射荧光强度对于入射角度变化的"平坦"范围进一步扩大.

音圈电机是一种常用的高动态性能驱动器.为了优化、简化不同音圈电机的控制算法调试过程,提出了一种基于LabVIEW FPGA的改进RBF神经网络控制算法.该网络采用3-输入的3层网络结构,通过梯度下降法对隐含层权值系数更新,实现对音圈电机的电流环控制.仿真结果表明,随着隐含层节点数增加,RBF神经网络控制算法性能将优于单神经元自适应控制算法.当隐含层节点数为6时,系统电流上升时间为14μs,相对于单神经元自适应控制缩短了26.3％.将该算法用于激光精密指向系统,实验结果表明,隐含层4节点时,电流上升时间为25μs.实验结果与仿真结果较吻合,验证了RBF神经网络算法的有效性.