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1.
研究一种针对白内障患者的潜在视功能检测仪。采用透射式视力分辨率板并且使进入眼瞳成像光束足够细和有足够的光能量,以致能够通过白内障患者云雾状晶状体中的微小间隙在视网膜上成像,移动透射式视力分辨率板调焦可测出患者的视度在-7D~ 12D之间的潜在视力。进行了光学系统结构设计和理论计算,进行了实验和测试。实验测试结果表明,该系统出瞳位置光斑直径D-=0.094 mm,测得视力与传统测试方法测得视力相一致。通过该仪器对白内障患者手术前检测,可比较准确预测置换人工晶体手术后达到的视力水平,这对医生和患者都具有重要参考价值。  相似文献   

2.
军用测试设备在无线通讯测试领域正面临着设备数量多、体积大、成本高、拓展性差的难题,合成仪器技术为此提供了良好的解决方案。文中提出了将合成仪器技术应用于通用无线数传测试设备,给出了具体的功能需求分析及合成仪器软硬件体系架构并对其中各功能模块的组合与共用方案进行了讨论,介绍了通用无线数传测试设备应用的合成仪器关键技术以及这些关键技术在硬件资源共用、测试性能指标和拓展性方面带来的改进与提升,能够实现通用测试设备向小型化、通用化、低成本化发展的目标。  相似文献   

3.
LHAASO(Large High Altitude Air Shower Observatory)WCDA(Water Cerenkov Detector Array)要求其读出电子学实现大动态范围下精确的时间和电荷测量,为此设计了一款前端读出芯片PASC(Pre-Amplifier and Shaping Circuit) ASIC(Application Specific Integrated Circuit),即将用于LHAASO WCDA第三水池的读出。为了满足对此芯片大批量测试需求,设计了此ASIC测试系统,实现了对芯片时间和电荷性能的自动化测试。在介绍此芯片基本工作原理的基础上,讨论了测试系统的设计方案和基本结构,包括硬件电路设计和自动化测试软件设计。该测试系统已应用于LHAASO工程项目的芯片筛选并且已完成了100片芯片的测试工作,能够通过中央控制软件,与多台仪器通讯,进行仪器控制,完成自动化测试和数据记录。这一自动化测试方法,更适用于大动态范围下、高精度读出芯片的性能测试和评估,大大简化测试流程,尤其能够大幅提升批量测试中大量重复性测试步骤的工作效率。文中展示了基于此测试系统已完成的100片芯片的测试结果,结果表明,芯片各项性能参数满足LHAASO第三水池工程应用需求。  相似文献   

4.
多光谱光学系统光轴平行性组合测试装置   总被引:5,自引:5,他引:0       下载免费PDF全文
介绍一种激光、白光和热像仪(或微光)三光合一观测仪器的捆绑式新型组合测试装置及其测试原理,并详细叙述了用该装置测试“三光”光轴平行性的过程和注意事项。该装置十字分划线的设计未采用常规的玻璃刻线工艺,而是选取电阻率较高的钨丝制成十字分划线,并在分划线的两端焊上电极,避免了测试时由于更换十字分划线靶标而可能产生的误差。该装置通过对观测仪器光轴平行性的检测和调试,为精确调校提供了依据,从而使3种光学系统的光轴平行性达到所需精度要求,对保证观瞄及测距的方向一致性起到了准确指示的作用。  相似文献   

5.
静电电位测量的现状与发展   总被引:1,自引:0,他引:1  
刘尚合  魏光辉 《物理》1995,24(2):108-112
静电电位是最重要的静电参数之一,其测量方法可分为接触式和非接触式两大类。“信息自屏蔽-电荷耦合”原理克服了传统的“接地屏蔽-电压输入”原理的缺点,其仪器具有输入电阻高、动态特性好、抗干扰能力强等特点,利用激光、光导纤维和现代电子技术研究新的测试原理和系统,是该领域当前的发展趋势。  相似文献   

6.
海水中的有色溶解有机物(CDOM)对海洋生态系统具有重要影响。针对当前CDOM测量的问题,基于Teflon AF 液芯波导(LWCC/LCW)技术,设计了一套全自动CDOM走航式测量仪。该仪器具有光程可调、测量动态范围广、灵敏度高等特点,适合于各类水体。其过滤和进样系统,实现了水样的自动过滤、进样和样品池清洗。基于LabVIEW语言开发的软件控制平台,可高效地控制仪器的运行状态和数据(光谱数据、GPS数据及海水温盐数据)的采集。通过对照实验和现场海上测试,证实了测量数据的可靠性和仪器的稳定性。  相似文献   

7.
风云四号B星干涉式红外探测仪发射前辐射定标   总被引:1,自引:0,他引:1  
干涉式红外探测仪(GIIRS)是我国地球静止轨道气象卫星风云四号B星的主要载荷,可观测大气上行红外高光谱辐射,因此可应用于大气温湿度廓线反演和数值天气预报模型同化。为了预测GIIRS在发射后的工作性能,于发射前在地面试验室热真空环境中采用黑体定标试验的方法,对仪器辐射性能进行了测试,测试的性能包括仪器灵敏度、辐射定标精度和动态观测范围。其中,长波红外通道的噪声等效辐射方差低于0.5 mW/(m2·sr·cm-1),中波红外通道的噪声等效辐射方差低于0.1 mW/(m2·sr·cm-1),两者均达到灵敏度设计指标。在辐射定标方面,经过非线性校正,长波光谱的平均定标偏差从1 K减小到0.2 K,且在220~315 K观测范围内达到0.7 K的设计指标;仪器在中波通道观测低温目标时受噪声影响较大,但在260~315 K的动态范围内,定标偏差也能够达到0.7 K的指标要求。  相似文献   

8.
杨瑞华  杨建伦  侯毅  叶繁  杨昊涵 《应用声学》2015,23(9):3245-3247
为了实现Z-pinch研究的大型实验中大数量多种类测试仪器的集中控制,利用虚拟仪器技术和并发控制技术管理数十台测试仪器,介绍了基于delphi和SQL servers数据库的管理控制系统设计,给出了实现控制的核心技术及软件实现代码;结果表明,并发控制技术的应用大大改善了原有的实验控制系统,获取50台仪器数据的时间降到40秒左右;这种基于虚拟仪器的并发控制技术,控制更多数量的测试仪器是可行的,对于从事实验仪器控制的技术人员有很现实的参考意义。  相似文献   

9.
多极子阵列声波成像测井已经成为测井中主要方法之一,在地层评价与油气田开发中有重要作用。在已有理论与数值模拟的基础上,经过近十年的技术攻关,我们已经在多极阵列声波成像仪器制造、测试与数值处理等主要关键技术方面都取得了长足的进展,具体包括高温正交偶极子发射换能、高温低频单极子换能器、声系测试、多极子阵列声波测井高温电路及仪器集成、资料处理及解释等主要方面。所研制的仪器及资料处理方法,经过与国外同类仪器的测井结果进行了对比分析,验证了所研发的仪器的可靠性和处理方法的正确性,这些关键技术为我国声学测井仪器装备技术研发和快速发展打下了基础,提供了技术支撑。  相似文献   

10.
杨立  胡晓民  王成 《光谱实验室》2003,20(5):772-776
应用ICP-AES法快速测定球团铁矿中的总铁、二氧化硅、氧化钙、氧化镁及三氧化二铝的含量。对测试仪器条件及元素谱线等相关参数进行实验和优化,对3种样品前处理方法所能达到的测试目标进行实验对比,对基体干扰及方法的准确度和精密度进行研究,并用标准物质验证。  相似文献   

11.
Remote detection technique can increase sensitivity of an NMR experiment by several orders of magnitude in microfluidic applications. Travel time experiment is a basic remote detection NMR experiment, which reveals the travel time distribution of the molecules flowing from the encoding coil region to the detector. In this article, we focus on analyzing how flow type (Poiseuille or plug flow), diffusion, dispersion and geometry of the flow channels are manifested in the travel time curves measured from microfluidic channels. We demonstrate that remote detection travel time experiment could be used even as an alternative NMR method for measuring self-diffusion coefficient of a fluid without magnetic field gradients. In addition, we introduce a modified travel time pulse sequence, which removes the signal of unencoded fluid spins as well as the background signal arising from the material inside or close to the detector.  相似文献   

12.
星载微光探测仪器可以在低照度条件下获取可见光至近红外谱段的云图及地面特征资料,是监测夜间和晨昏时段低云大雾的最有效手段。本文介绍了星载微光探测原理;综述了国内外星载微光探测仪器的发展历程,对其卫星系统、仪器技术指标、成像关键技术、数据特点等做了详细论述;最后总结了星载微光探测技术在低云大雾监测、城市灯光和火情监测、烟雾和尘埃监测等方面的应用,它可为我国气象卫星发展相近载荷起到借鉴作用,并完善和丰富我国现有的气象业务观测体系。  相似文献   

13.
介质型脉冲高能中子探测器   总被引:2,自引:0,他引:2  
首次报道一种基于反冲质子法和高速带电粒子在物质表面引起二次电子发射的高能中子探测方法,研制成功的新一代强流脉冲高能中子探测器,即介质型脉冲高能中子探测器.与传统的强流脉冲中子探测器相比,该探测器对中子的探测及信号的传输过程是在介质中完成的,因而不需要真空和高压也可以正常工作,并具有多项优异的物理性能.该探测器的输出信号来自于高能中子在聚乙烯转换靶产生的高能反冲质子和这些质子穿越电荷收集极表面时产生的部分二次电子.选择适当的卡阈吸收片和电荷收集极材料,二次电子在探测灵敏度中的份额及其随能量的变化可由实验测定.  相似文献   

14.
The results of computer simulation of heat propagation processes in the three-layer detection pixel with the superconducting layers of thermoelectric detector after the absorption of single photons energy of 1–1000 eV are presented. We consider the different geometries of the detection pixel consisting of CeB6 or (La,Ce)B6 thermoelectric sensor, absorber and heat sink of Nb, Pb or YBCO superconductors. The computations based on the heat conduction equation from the limited volume are carried out by the three-dimensional matrix method for differential equations. It is shown that by changing the materials and dimension of the detection pixel elements, as well as the operating temperature of the detector enables one to obtain the detector to register the photons within the given spectral range, required energy resolution, and counting rate. Such a detector has a number of advantages that allow one to consider the thermoelectric detector as a real alternative to the most promising single photon detectors.  相似文献   

15.
白藜芦醇浸提纯化过程在线检测条件的研究   总被引:2,自引:1,他引:1  
通过实验确定了虎杖白藜芦醇乙醇浸提液的HPLC检测条件。最佳检测条件为,Extend反相ODS柱0.46cm×15cm,紫外检测器检测波长240nm,V(甲醇)∶V(水)=50∶50的流动相,1mL/min的洗脱流速,室温。该方法灵敏、方便、可靠、快速,适用于白藜芦醇提取、纯化中的在线检测。  相似文献   

16.
微振动光电检测与数据采集系统的设计   总被引:1,自引:0,他引:1  
提出了一种新的光学非接触式测量方法测量了物体的微振动振幅。用激光作为光源,以四象限硅光电池[1]作为光电探测器,借助三角测量原理,投射在振动源表面的激光反射光束在光电探测器上产生平面位移,将位移信号放大,通过A/D模块采集电压数值,并通过串口通信机制在PC终端实时显示。实验结果表明,该方法原理正确,灵敏度高,便于实现连续、快速、自动化检测,在工业在线检测方面具有良好的应用前景。  相似文献   

17.
Using photoemission intensities and a detection system employed by many groups in the electron spectroscopy community as an example, we have quantitatively characterized and corrected detector non-linearity effects over the full dynamic range of the system. Non-linearity effects are found to be important whenever measuring relative peak intensities accurately is important, even in the low countrate regime. This includes, for example, performing quantitative analysis for surface contaminants or sample bulk stoichiometries, where the peak intensities involved can differ by one or two orders of magnitude, and thus could occupy a significant portion of the detector dynamic range. Two successful procedures for correcting non-linearity effects are presented. The first one yields directly the detector efficiency by measuring a flat-background reference intensity as a function of incident X-ray flux, while the second one determines the detector response from a least-squares analysis of broad-scan survey spectra at different incident X-ray fluxes. Although we have used one spectrometer and detection system as an example, these methodologies should be useful for many other cases.  相似文献   

18.
It has been demonstrated that glass display of mobile phones can be used as a device for accident dosimetry. Published studies concentrated on the experimental investigation of parts of the glass display. In the work presented here, the experimental results are compared with results of radiation transport calculations using the Monte Carlo code MCNP5.An experimental setup of an irradiation of an extracted glass display is simulated. The simulation is then extended to a simulation of a modern day mobile phone consisting of all major parts. Simulations are performed for various irradiation conditions and different geometric and material properties.The results of the simulation show a good agreement with the experiments for an extracted glass sample as well as for an actual modern mobile phone. The glass display is exposed to radiation in various angular and energy distributions. Simulated results were compared to experimentally determined results. The effects of the irradiation condition on the photon energy dependence were investigated and variations in the material constants of the display glass composition were discussed. This work affirms the usability of a mobile phone as a versatile and flexible accident radiation detector.  相似文献   

19.
应用FLUKA 软件包对NE213 液体闪烁体中子探测器的探测效率进行了蒙特卡罗模拟,通过Birks 公式将中子产生的次级粒子的能量沉积转化为相应的光输出。根据不同探测阈值对模拟得到的光输出进行积分处理,计算出给定能量下探测器的中子探测效率。将模拟得到的闪烁体光输出、中心探测效率和平均探测效率随中子入射到探测器前表面位置的变化与实验数据进行比较,结果显示,FLUKA 模拟结果与实验值符合得很好,这为中子探测器的设计提供了可靠保证。A NE213 liquid scintillation neutron detector was simulated by using the FLUKA code. The light output of the detector was obtained by transforming the secondary particles energy deposition using Birks formula. According to the measurement threshold, detection efficiencies can be calculated by integrating the light output. The light output, central efficiency and the average efficiency as a function of the front surface radius of the detector, were simulated and the results agreed well with experimental results.  相似文献   

20.
The present paper describes the design and simulation results of a position-sensitive charged particle detector based on the Double Sided Silicon Strip Detector (DSSSD). Also, the characteristics of the DSSSD and its testing result were are discussed. With the application of the DSSSD, the position-sensitive charged particle detector can not only give particle flux and energy spectra information and identify different types of charged particles, but also measure the location and angle of incident particles. As the detector can make multi-parameter measurements of charged particles, it is widely used in space detection and exploration missions, such as charged particle detection related to earthquakes, space environment monitoring and solar activity inspection.  相似文献   

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