红外高发热精密探测器中恒温控制模块设计

为了提高红外探测器在实际工作中的性能和稳定性,设计了一种针对高发热红外精密传感器的自动调节探测器外围温度的装置。该装置利用C8051F350单片机对半导体制冷片进行制冷、制热和不同功率运行的控制,保持探测器外围温度的稳定。通过PID算法编程,结合多点测量实现环境温度的均匀性和稳定性。实验结果表明,在一天的工作时间内,该装置可使探测器外围的温度控制在20℃,控制精度为±0.5℃,显著提高了探测器的性能。     

紫外光电探测器高精度线性测量装置

基于双光阑法，研制了一种紫外光电探测器高精度线性测量装置，主要由高稳定钨带灯、带有快门的双光阑屏、石英透镜、紫外光栅双单色仪和计算机组成，测量波长范围为200-400nm.给出了该装置的原理、测量方法及数据处理方法。测量过程由计算机配套专用软件进行自动控制。利用该线性测量装置，对光电倍增管探测器进行了线性测量。实验结果表明：该装置测量精度高、速度快，测量不确定度小于O．05％，可应用于对精度要求高的紫外光电探测器线性度的测量。     

极紫外波段空间相机的辐射定标

考虑极紫外波段空间相机尚无合适的辐射定标方法和装置,本文提出了适用于该波段的小目标成像辐射定标方法并基于该方法在实验室建立了辐射定标装置。提出的标定方法首先使用标准传递探测器标定小目标的辐射亮度;然后,用待定标相机中心视场对该小目标成像,获得中心视场部分的辐射强度响应度;最后,通过调整转动结构使不同视场对该小目标成像,得到不同区域的辐射强度响应度。构建的辐射定标装置由光源系统、标准传递探测器、真空罐及四维运动转台等组成。光源系统包括空心阴极光源、极紫外掠入射单色仪、准直反射镜,能够出射工作波段的准直光束;标准传递探测器标定出光束照度并计算得到小目标的辐射强度;运动平台使相机能够以不同视场角对小目标成像,测得不同视场的辐射强度响应度。利用该装置对一台极紫外相机进行了辐射定标实验,并进行了误差源分析。实验结果表明该装置的定标精度优于15%,能够实现整机状态下的辐射定标。     

IRP-9400型红外方位探测系统实验装置的研制

介绍了应科研教学需要而研制的一种多功能红外方位探测系统实验装置。该实验装置是用于演示和模拟红外方位探测技术方法基本原理与特性的实验仪器，它采用了仪器化外形设计和积木式光机结构。该装置由靶目标装置、光学系统、各类调制盘、红外探测器和信号处理系统五部分组成，可根据不同的实验目的，通过更换各种类型的调制扫描部件以及更换不同的调制盘图案进行各类红外跟踪系统中位标器的方位探测方法实验。该装置的光学系统采用了可变焦的物镜设计以及可调焦场镜设计，调节物镜与杨镇焦距可改变光机系统的性能参数。该仪器不仅在科研预研时作为一种有效的模拟实验、调整参数的实验参考工具，还可作为一种灵活、多功能的教学实验仪器。由于该仪器光学系统以及探测器均采用近红外元件以替代昂贵的红外元件，因此该仪器具有灵敏度高，且造价低廉的特点。     

核电站光电感烟探测器的防凝露装置设计

以核电站火灾报警系统中的光电感烟探测器为研究对象,结合其工作原理,分析了潮湿对火灾探测误报影响,提出了一种光电感烟探测器防凝露装置的设计方法。从设计的合理性和安全性等方面进行论证,并通过试验验证防凝露装置的性能。试验结果表明,该防凝露装置可以解决由潮湿引起的误报问题。     

基于六轴串联机械手的双向反射分布函数测量装置

由于现有的双向反射分布函数(BRDF)测量装置多为3轴系统,不能完全实现样品表面以上2π空间的全角度BRDF测量,本文研制了新型BRDF测量装置。该新型装置采用高精密六轴串联机械手作为待测目标的定位机构,使待测目标在测点进行三维转动;采用竖转台作为探测器探头的定位机构,使探头指向绕测点进行一维转动,从而形成4维转动以构建BRDF测量所需的4角几何关系。研制的装置可测量的入射和反射光束角度为:方位角0~360°、天顶角0~70°;光谱可扫描区350~2 500nm。BRDF测量过程由测控软件控制,可高精度、无遮挡、全自动、快速地构建BRDF测量几何关系,一次待测目标和探测器定位以及光谱扫描、传输、显示、存储平均用时约8s,测量不确定度优于2.5%(k=2)。     

紫外光阴极辐射灵敏度的测量误差

光阴极辐射灵敏度是衡量紫外探测器响应能力的一项重要指标,实现其准确测量至关重要。本文建立了某型紫外探测器光阴极辐射灵敏度测量方法,搭建了实用的紫外光阴极辐射灵敏度测量装置,重点分析了利用该装置进行紫外光阴极辐射灵敏度测量时的影响因素,对比了紫外窄带滤光片、光栅单色仪、辐射照度计和辐射功率计等不同组合方式进行光阴极辐射灵敏度测量时的误差情况,得出光栅单色仪配辐射功率计方式在光阴极辐射灵敏度测量时的误差最小,扩展不确定为9%,相比其它三种组合19.4%、19%和11.2%的扩展不确定度具有绝对优势。该研究成果用于辅助国产紫外探测器技术研发,为进一步改进提升其技术性能提供了有效且准确的检测手段。     

放射性废物分拣系统测量装置设计

介绍了放射性废物分拣测量系统装置的设计。该装置由传送装置和探测装置组成,通过振动给料斗均匀送料至传送带上,由机械挡刀确定土壤的厚度,放射性废物在传送带运输过程中进行辐射探测器的探测。并对测量装置中的主要部件和探测方法进行具体设计分析。采用双探测器两段式探测的方法进行粗、精探测,使探测结果更精确,对屏蔽体厚度进行具体计算。该装置能够实现全程无人操作和全自动化的探测和分拣等特点,可满足不同放射性固体废物的分拣与测量。     

车用自动灭火装置的设计

本文通过对车辆起火原因和车辆结构特点以及车内燃烧物质进行分析,然后根据灭火要求设计出自动灭火装置。自动灭火装置主要是将灭火系统加入到汽车构造中,减少车辆自燃引起的危害。通过感烟探测器、火焰探测器监测汽车是否发生自燃。若探测器检测到燃烧信号,灭火控制器控制车上的灭火装置开启,实现迅速灭火,减少车辆自燃的危害。     

光电探测器相对光谱灵敏度自动测量装置

本文介绍了一种光电探测器相对光谱灵敏度自动测量装置,其分光装置为56W型小型光栅单色仪,采用无运动部件的双光路替代法,以标定过的硅光电探测器作参考基准,由微机实现波长的步进控制、数据采集和数据处理,具有精度高、结构简单、价廉等特点。     

An inexpensive and highly efficient device for observing a transmitted electron image in SEM

An inexpensive, efficient device that supplies a transmission mode to the conventional SEM has been developed. The transmitted electrons strike a metal plate, and these generate secondary electrons that are proportional to the quantity of the transmitted electrons. The generated electrons are collected by the secondary electron detector. Hence, the performance of this device is influenced by the number of secondary electrons generated in the metal plate. In order to construct a device that can attain the best transmitted electron image, the signal-to-noise ratio of images, obtained from various trial devices, were measured by a newly-developed digital image processing program. When the material and shape of the device are selected, to produce high-secondary emission, the efficiency of the device compares with that of a relatively expensive standard detector system (scintillator detector).     

Sensitive temperature gradiometer for use at low temperatures

A device capable of very sensitive temperature gradient measurements in the presence of relatively large ambient temperature fluctuations is described. The device uses a pair of 'matched' superconducting thin films in a bridge arrangement, with a SQUID magnetometer probe as the null detector.     

The Magnetizing System of an In-Tube Flaw Detector with Transverse Magnetization

Results of calculations of the magnetizing system for a flaw detector are presented. The device is intended to determine longitudinal stress-corrosion cracks in pipes in underground trunk pipelines. The calculation results are compared to the experimental data obtained with a special model of the magnetizing device. The optimum parameters of magnetizing elements, as well as their mutual location that ensures the magnitude and direction of the magnetic flux in a pipeline's wall that are required for reliable identification of longitudinal defects, are determined. The obtained results were used as a basis for designing the magnetizing system's module, which is the main unit in each in-tube flaw detector.     

Inverse-fourth apparatus for photometric calibrations

A new photometric device is described which can perform direct, as opposed to comparison, measurements of optical transmittance, without bootstrapping, over a range of nearly six orders of magnitude. According to the demonstrated principle of operation, the amount of light flux received at a detector is proportional to the inverse-fourth power of the effective source-to-detector distance. As the device is configured, the adjacent source and detector are stationary while a flexible light guide, which collects light from the source and re-emits it toward the detector, moves on a carriage. The transmittance, T, of a filter is measured in terms of the ratio of carriage positions, for constant detector output, with and without the filter in the light path; the optical density is then D=-logT. The position of the carriage, relative to the source-detector plane, is measured over the 3 m range of travel with a resolution of 0.01 mm. Operated with a 1000 W tungsten-halogen lamp as a source, a photomultiplier as a detector, and either an integrating sphere or opal glass for diffuse collection at the detection plane, the system is designed to attain an overall accuracy of +/-0.5% for ANSI PH2.19 diffuse transmission densities up to 6.0 density units, corresponding to +/-0.1% for transmittances above 0.5000 transmittance units and to +/-3% for transmittances between 0.000001 and 0.0001 transmittance units.     

基于PSD的小型激光测头的设计

利用位置敏感探测器(PSD)频率响应高、接口电路简单、数据采集快等特点,设计了一种小型、动态激光三维测头。该测头采用激光三角法原理,利用凹凸双透镜光学系统进行激光缩束以提高测量精度,利用平面反射镜增加光程以减小体积,并对各具体参数和整体结构进行了详细的设计。该测头系统拥有体积小,精度高,反映快的优点。     

Simple laser pulse energy monitor

A simple and inexpensive relative energy monitor for short laser pulses is described. The three basic units of this system are an integrating detector circuit, an amplifier, and a peak detector and hold circuit. With this device one can measure optical pulse energies (at 1.06 microm) as small as 1.0 nJ with an electronic accuracy of approximately 1%.     

透气性测试装置密封结构的优化

基于压差法的薄膜透气性测试装置,其测试结果受测试装置的密封性能、测试的环境温度及压力和温度检测器检测性能的影响.在压力和温度检测器的检测性能给定和环境温度相对稳定的情况下,影响测试结果的主要因素是测试装置的密封性能,以目前现有的密封材料和密封技术,测试装置的密封性能主要与其密封结构和相应的结构比有关.基于此,给出测试装置双密封结构的系统临界时间求解表达式；分析测试装置双密封结构压力变化特性和时间流阻容量常数特性；得出在总密封体积限定的条件下双密封结构的优化结构比;给出相应的仿真结果和试验结果.结果表明:该双密封结构的优化是正确和合理的.为透气性测试装置双密封结构优化设计的实际应用提供了理论依据.     

Detection of gas pipe wall thickness based on electromagnetic flux leakage

Based on electromagnetic flux leakage (EMFL), a nondestructive testing (NDT) technique for the detection of gas pipe wall thickness is presented, and its principle and feasibility is evaluated by means of equivalent magnetic circuit analysis and finite element analysis. An online NDT device adopting this technique is developed, and its structure and working principle are introduced in detail. This device is composed of a detector array with 32 pipe wall thickness sensors that employ a Hall element as the element for sensing the magnetic flux density, and it can be adapted to pipe diameters from Ø400mm to Ø650 mm. On the basis of the experimental investigation for this device, the influences of some factors on thickness measurement, namely the excitation current, excitation coil turns, gap distance, concentrator of the magnetic field, magnetization time, and number of sensors in the detector array, are revealed and the optimal excitation voltage for the sensors of the detector array is selected. The measuring calibration is given to establish the relationship between the pipe wall thickness and the output voltage of the sensors. The results show that the proposed EMFL for measuring the wall thickness of ferromagnetic pipe is feasible, the technical parameters of the sensor are important for improvement of measurement precision and resolution, and the developed device has precision, resolution, and a linear output curve. Carried by the developed gas pipeline inspection robot through a universal joint, this NDT device can move inside the gas pipeline and monitor the state of the pipe wall.     

Evaluation of a hybrid pixel detector for electron microscopy

We describe the application of a silicon hybrid pixel detector, containing 64 by 64 pixels, each 170 microm(2), in electron microscopy. The device offers improved resolution compared to CCDs along with faster and noiseless readout. Evaluation of the detector, carried out on a 120 kV electron microscope, demonstrates the potential of the device.     

RESPONSE TIME MEASURING SYSTEM FOR ORGANIC ELECTROLUMINESCENT DEVICES

In order to analyze the optoelectrical characteristics of organic electroluminescent (OEL) devices, a response time measuring system was established. This system contains a brightness detector with a fast response photoamplifer tube (PMT), a power supply, and a PC computer with an ultra-fast data collection card. The fast response data collection card installed in the PC computer controls the entire course of measurements. The power supply applies a constant voltage to the brightness detector and a pulse voltage to the OEL device to enable it to emit light. The brightness detector receives the light emitted from the OEL device. Both the brightness and driving voltage signals are transferred directly to the computer. Then the voltage-time and brightness-time curves are simultaneously recorded and, finally, the device response time is easily obtained from these curves. The lowest response time of this system that can be measured is 50 ns. With this system, the response times of the OEL devices driven by different voltages have been measured.