多波段伪装涂料制备及性能表征

多波段兼容伪装涂料是伪装技术发展的难点之一。通过低发射率伪装颜料的合成与热红外透明树脂的选择制备了绿色伪装涂料，利用近红外光谱测试和热红外成像分析表明，该绿色伪装涂料在可见光、近红外、热红外等波段都具有较好的伪装效果。     

高光谱热红外温度发射率分离的相关-小波法

针对高光谱数据热红外温度和发射率反演为病态方程且易受大气下行辐射噪声干扰的问题,提出了基于相关性和小波滤波相结合的高光谱热红外温度发射率分离方法,即相关-小波法。在相关性方法的基础上,引入小波降噪的思想,生成一系列温度梯度,在不同温度梯度下,带入大气下行辐射计算得到的发射率曲线和不考虑大气下行辐射直接小波滤波得到的发射率曲线计算相关性,取相关性最大时的温度为反演温度。同时在反演发射率时利用相关性计算不同尺度的小波信号所占的比例合成发射率曲线。模拟数据结果显示:相关-小波法在温度梯度为0.01K时,温度反演平均误差为0.05K,并且相关-小波法在温度反演精度和发射率反演精度上都优于相关性方法和小波法。由此表明,该算法可一定程度上抑制大气校正不准确引入的误差,有效提高热红外温度和发射率的反演精度。     

高效节能红外炉的应用与改进

本文阐述了作为国家级推广新技术的高效节能红外炉应用多年的效果。此炉以高发射率红外涂料为核心，采用红外电阻带及红外复合炉衬，节能２０￣４０％以上，并显著提高工效和温度均匀性；讨论了获得这些效果的条件及机理，报道了此炉在使用中出现的问题及其改进措施。     

轧机的红外温度监测

本文介绍了红外测温仪的功能、适用范围和温度检测的步骤;为确保检测结果的准确,从使用环境选择适当的测温仪器、靠近目标、发射率的影响等方面阐明了注意事项,并以该测温仪在轧机的应用来说明。     

超临界水蒸气氧化的12Cr钢发射率试验研究

对于大型旋转机械的强度设计和寿命评估而言,其表面温度是一个不可或缺的重要参数。使用红外辐射测温技术可以实现对旋转机械表面的非接触温度测量。由于长期工作在高参数的水蒸气环境中,汽轮机转子表面的氧化膜对红外辐射测温有重要影响。为研究转子钢的氧化对红外辐射测温的影响,建立金属试样在超临界水蒸气(24 MPa、400℃)环境中进行氧化及试样带宽发射率测量的试验台架,实现用于超(超)临界汽轮机转子的材料——精炼12Cr钢试样在超临界水蒸气环境中的氧化,并使用单色测温仪测量氧化后精炼12Cr钢试样的发射率。结果表明,随着氧化的深入,精炼12Cr钢试样发射率的分散性及其随温度变化的速度逐渐降低,认为可以选择发射率的某个测量值(如0.88)作为设定值,使用单色测温仪对金属目标温度变化进行监测。为实现红外测温技术在汽轮机转子表面温度检测中的应用奠定基础。     

关于提高红外监测准确性的思考

本文通过对监测方式、运行状态、设备表面发射率、大气衰减、气象条件和环境等影响红外检测结果的五个方面进行分析,提出了提高红外检测准确性的对策,对在电力设备和其它设备中开展红外检测工作具有一定的借鉴作用。     

基于方向发射率校正的红外测温补偿方法

红外热成像仪具有实时在线、非接触获取被测对象二维温度分布等优点,在钢铁、农业、电力电子等众多领域应用广泛。但是,红外测温结果容易受到干扰因素的影响。针对方向发射率变化引起的红外测温误差,本文提出了基于方向发射率校正的红外测温补偿方法。首先,基于红外测温原理,构建了针对方向发射率变化的红外测温补偿模型。其次,为确定补偿模型中的方向发射率,利用红外热像仪和激光扫描仪构建的三维热成像系统,提出了基于参考体的方向发射率校正方法。然后,通过多项式拟合确定方向发射率随视角变化的规律。实验结果表明所提红外测温补偿方法可以有效降低方向发射率变化造成的红外测温误差,经过补偿温度后,红外测温最大误差由9.64℃降低为2.97℃,标准差由3.57℃降低为0.71℃。     

六氟化硫气体探测用10.56μm窄带滤光片的研制

在六氟化硫气体检测中经常会使用红外气体传感器,红外滤光片是红外气体传感器的核心元件。对六氟化硫的红外气体探测中,研制性价比较高的10.56 μm窄带滤光片尤其重要。首先,通过测量空气和六氟化硫气体的红外吸收光谱,明确了基于NDIR技术的红外传感器需要的滤光片的光谱指标。然后,使用单晶硅为基底,锗和硫化锌为高、低折射率材料,设计了窄带膜系和截止膜系两种膜系结构。通过选择合理的工艺参数,镀制了中心波长为10.562 μm、带宽为175 nm、峰值透射率为80.2%、截止范围为2~18 μm（除通带）的红外滤光片。最后,经环境测试和传感器测试,证明该滤光片满足使用要求。     

基于涂料性能参数的红外隐身技术

随着红外制导技术的日趋成熟,其对军事目标的生存能力形成了更加严峻的挑战。在模拟出目标表面温度的基础上,研究与分析了隐身涂料的性能参数短波吸收率 、长波吸收率 与发射率 对地面目标表面温度以及红外探测系统作用距离的影响。分析结果表明： 、 、 均会对目标表面温度与作用距离产生影响, 、 取值越大,目标表面温度越高,而 取值越大,目标表面温度越低;针对具体的背景温度 ,一定的 、 与 取值范围,作用距离随 、 的降低而减小,随 的增大而先减小后增大,并发现一个最佳发射率 使得作用距离最小。其研究成果对红外隐身涂料的设计、选型与使用有非常重要的实际意义。     

红外高光谱干涉仪辐射定标误差敏感性因子的仿真分析

鉴于对高精度高时空分辨率大气探测资料日益增长的科研和业务需求,我国正大力发展星载红外高光谱探测系统。星载红外高光谱干涉仪光机结构复杂,仪器状态会显著影响其定标精度。本文通过理论分析和仿真实验,分别讨论了内黑体发射率、低温黑体发射率、内黑体与环境温度差、非线性系数以及直流电压演算等误差敏感性因子影响辐射定标精度的特征。分析表明定标辐射偏差的绝对值与内黑体/低温黑体发射率呈线性关系,且与内黑体与环境温度差、非线性系数、直流电压呈正相关;提高内黑体发射率和低温黑体发射率到0.985以上、控制内黑体与环境温度差在0.6 K左右、控制干涉仪的非线性效应系数低于0.04,这些方案均是实现0.1 K辐射定标精度的必要条件;辐射定标参数对定标辐射的影响特征结合地面真空实验的定标参数估计,可以迭代得到已测得和未知的定标参数的最优估计,从而提高定标精度。本文的研究结果对于红外高光谱干涉仪的参数设计以及辐射定标误差来源的识别和订正有着十分重要的意义。     

A dual-band adaptor for infrared imaging

A novel imaging adaptor providing the capability to extend a standard single-band infrared (IR) camera into a two-color or dual-band device has been developed for application to high-speed IR thermography on the National Spherical Tokamak Experiment (NSTX). Temperature measurement with two-band infrared imaging has the advantage of being mostly independent of surface emissivity, which may vary significantly in the liquid lithium divertor installed on NSTX as compared to that of an all-carbon first wall. In order to take advantage of the high-speed capability of the existing IR camera at NSTX (1.6-6.2 kHz frame rate), a commercial visible-range optical splitter was extensively modified to operate in the medium wavelength and long wavelength IR. This two-band IR adapter utilizes a dichroic beamsplitter, which reflects 4-6 μm wavelengths and transmits 7-10 μm wavelength radiation, each with >95% efficiency and projects each IR channel image side-by-side on the camera's detector. Cutoff filters are used in each IR channel, and ZnSe imaging optics and mirrors optimized for broadband IR use are incorporated into the design. In-situ and ex-situ temperature calibration and preliminary data of the NSTX divertor during plasma discharges are presented, with contrasting results for dual-band vs. single-band IR operation.     

Detection and differentiation of biological species using microcalorimetric spectroscopy

We report on the application of infrared (IR) microcalorimetric spectroscopy ( micro -CalSpec) to the identification and detection of trace amounts of biological species. Our approach combines principles of photothermal IR spectroscopy with ultrasensitive microcantilever (MC) thermal detectors. We have obtained photothermal IR spectra for DNA and RNA bases and for Bacillus Cereus (an anthrax simulant) in the wavelength range of 2.5-14.5 micro m (4000-690 cm(-1)). The measurements are accomplished by absorbing biological materials directly on a MC thermal detector. The main advantage of the developed micro -CalSpec is its unprecedented sensitivity as compared to any of the previously explored IR techniques, including FTIR and photothermal FTIR methods. Our results demonstrate that <10(-9)g of a biological sample is sufficient to obtain its characteristic micro -CalSpec spectrum that contains information-rich chemical (vibrational) signatures. This opens up a new opportunity to create inexpensive high-throughput analytical systems for biochemical detection.     

烷化核酸碱基结构的特征研究

采用FTIR、HPLC和 GC-MS等分析手段研究大气环境中典型污染物苯并(a)芘与DNA碱基鸟嘌呤加合物的结构特征,首次测定苯并(a)芘等与鸟嘌呤加合物的红外光谱,加合反应后,烷化核酸碱基红外振动峰的峰形、峰位都发生明显变化。为进一步分子水平研究烷化核酸碱基类加合物提供依据。     

基于改进多尺度分形特征的红外图像弱小目标检测

为提高红外图像弱小目标检测的准确率和实时性,在分析用于红外图像增强的分形参数K相关的多尺度分形特征(MFFK)基础上,提出了一种基于改进多尺度分形特征(IMFFK)的红外图像弱小目标检测算法。首先,将基于地毯覆盖法的分形维数计算公式代入MFFK计算公式,提出了一种改进多尺度分形特征(IMFFK)用于图像增强。其次,对IMFFK特征计算进行简化,采用自适应阈值分割得到感兴趣目标区域,提出了一种具有较高计算效率的红外图像弱小目标检测算法。最后,通过仿真图像分析了主要参数对图像增强和算法耗时的影响,采用红外真实图像进行了算法检测性能测试,并与当前基于局部对比度测度的目标检测算法进行了对比。实验结果表明,提出的算法虽然在一些检测场景具有较多虚警,但能同时适用于弱小目标和较大目标检测,且无论目标为亮目标或暗目标。提出算法对于低分辨率红外图像(320×240)检测接近30 frame/s。提出算法具有较强的适用性,能够检测出红外图像中具有较高局部对比度的目标。     

一种可直接脉冲调制的MEMS红外激发源

针对红外气体探测器对光源的要求,结合现有MEMS(微机电系统)工艺及与其兼容的IC工艺,研制了一种可用于红外多气体传感器的脉冲式MEMS辐射光源。该光源主要有Si₃N₄/SiO₂的复合支撑层和铂金发热电极组成,可以产生相当于黑体300~800 K的红外辐射,在温度T＝1 106 K时有λ=2.62 μm峰值辐射波长;并且光源有足够强的辐射强度和2~15 μm红外辐射波段,能够满足大部分气体在2~14 μm波长范围内特征的吸收谱线的要求。经过对辐射元的动态测量可知,辐射源的动态调制频率可达到50 Hz,完全能够满足气体测量对所需红外光源调制频率的要求。     

Infrared scanning for biomedical applications

The great interest in using infrared imaging for biological and medical applications is motivated by the harmless interaction of small doses of infrared radiation with biological objects and by the technical ability of infrared digital cameras to generate, produce, store, and display the resultant images in situ. In this study, we review the state of the art of infrared (IR) imaging in comparison with well established medical imaging techniques such as ultrasound and x-rays. We demonstrate for the first time that by using IR transmitted light, one can observe bones, tendons, cartilages, and other tissues. The IR long-focus scanning microscope was built to allow two modes of scanning. The first mode is when illumination of a biological object is performed at the same angle of view with different IR wavelengths lambda. The second mode is when, for fixed wavelength lambda, scanning of the source of light around the object is performed. We discuss the special image processing methods and potential applications of the new scanner for medical diagnostics. This novel, low-cost IR imaging system (hardware and software) allows one to scan biological objects such as human arms, legs, palms, and fingers to differentiate tissues, tendons, muscles, ligaments, blood vessels, bones, and cartilages. Some of these objects cannot be detected by conventional x-rays.     

Use of coded infrared light for mobile robot localization

This paper presents mobile robot localization using coded infrared light as artificial landmark. Different from RFID, coded infrared light has highly deterministic characteristics. It is implemented with IR LEDs and phototransistors. By putting several IR LEDs on the ceiling, the floor is divided into several sectors and each sector is set to have a unique identification. Coded infrared light tells which sector the robot is in, but the size of the uncertainty is still too large if the sector size is large, which usually occurs. Dead-reckoning provides the estimated robot configuration, but the error becomes accumulated as the robot travels. This paper presents an algorithm that combines both the encoder and the coded infrared light information so that the size of the uncertainty becomes smaller. It also introduces a framework that can be used with other types of artificial landmarks. The characteristics of the developed coded infrared light and the proposed algorithm are verified from experiments.     

Preparation of Ultrafine SiO2 Powder from Rice Husk and Properties of Its Infrared Spectrum

This paper discussed impact of temperature on the size distribution in preparing ultrafine silica from rice husk.The samples prepared were analyzed with infrared spectrum,and the relation between the particle size and intensity of characteristic absorption peak of IR at center around 1 100 cm-1 was disscussed with the baseline method.Results show that when the temperature is 650 ℃ and roasting time is 11 h,at optimal reaction conditions,the size distribution of the ultrafine silica powder prepared is relatively concentrated,and the average particle size is 199.5 nm.Moreover,the characteristic absorption band of IR is broadening gradually along with particle size decreasing.     

碳纳米管压阻微悬臂梁红外热探测器的研究

研究了压阻复合层微机械悬臂梁红外探测器的热挠曲理论模型。利用IC工艺和微机械加工技术设计制作了一种硅/铝/碳纳米管三层微机械悬臂梁红外探测器,该探测器基于硅和铝两种材料热膨胀系数的差异,存在双物质效应,不同温度下梁的挠度不同,其形变可通过梁根部的压敏电桥检测。为提高探测器的红外吸收特性,实验探索出了在微机械悬臂梁上涂敷碳纳米管吸热层的工艺方法。实验研究了具有碳纳米管薄膜吸热层的三层微机械悬臂梁红外热探测器对红外辐射的响应规律,结果表明涂敷碳纳米管吸热层使响应灵敏度提高近一倍。     

太赫兹技术对营养品中蛋白质含量的研究

采用太赫兹时域光谱(THz-TDS)和红外光谱分析技术,研究了3种奶粉、杏仁粉和白砂糖的光学性能和光谱特性。通过对比样品在1658 cm-1和1747 cm-1处的红外光谱吸收峰,可以判定蛋白质和脂肪含量的差别。对比样品在THz波段的吸收系数和折射率,蛋白质含量较高的样品其吸收系数和折射率较高。观察样品的红外吸收峰强度和位置难以定量分析样品的蛋白质含量,但可以利用样品在THz波段的吸收系数与折射率有效地判定营养品中蛋白质的含量。实验结果表明蛋白质在太赫兹波段比在红外波段有更好的区分性,THz-TDS技术有望为营养品中蛋白质含量检测提供一种有效的分析手段。