简介:Atemperaturesensorbasedonpolarizationnon-reciprocity(PNR)infiber-opticSagnacinterferometer(FSI)wasproposed.Theexperimentalstudywasmadeprimarilyandtheresultsagreewiththeorywell.Discussionshowsthatthiskindoftemperaturesensorcanachievehighprecisionandhavegreatapplicationpotential.
简介:Thetime-of-flightmassspectrum(TOFMS)relativetotheresonanttwo-photonionizationofgasphasep-dichlorobenzenewasobtainedinthewavelengthrangeof240-250nmbyahome-madesystem.Aspecialdesignwasmadetoreducetheeffectofmemoryontheinnerwallofthesampleinletsystemsuitablefortheinvestigationofsemi-volatileorganiccompound.Inthiswavelengthrange,p-dichlorobenzenemoleculesfirstlyabsorbedonephotontobeexcitedfromthegToundstate~1A_g(S_0)tothefirstexcitedstate1B2u($1),thenabsorbedanotherphotontobeionized.Therelationshipbetweenthesignalintensityofp-dichlorobenzenemolecularionC_6H_4~(35)Cl_2~+at248-nmwavelengthandthelaserpowerwasgiven.The1.52powerindexofC_6H_4~(35)Cl_2~+wasatypicalidentificationofthe3/2powerlaw.TherelationshipbetweentheionsignalintensityofC_6H_4~(35)Cl_2~+andthesampleconcentrationwasclosetoalinearoneintheppm(V/V)range,whichledtoadetectionlimitof125ppb(V/V)forp-dichlorobenzene.
简介:通过分析F-P扫描干涉仪的工作原理,基于STC89C52RC单片机,采用PA93功率放大器驱动压电陶瓷,设计了1064nm平平腔结构的F-P扫描干涉仪。腔镜反射率为98%,精细度156,腔长0.1~100mm连续可调,对应自由光谱区1.5~1500GHz和分辨率9.65~9650MHz。压电陶瓷驱动电压和频率通过4×4矩阵键盘,可以在0~200V和1~30Hz连续可调,显示在1602液晶屏上。同时可以通过RS232串口与计算机通讯,在上位机使用LabVIEW软件界面方便地设置压电陶瓷驱动电压和频率。最后使用该F-P扫描干涉仪,对激光二极管泵浦Nd:YVO4激光器纵模进行了测量,验证了整个系统的工作性能。
简介:Byusingagraded-indexmultimodefiber(GI-MMF)witharelativelyflatindexprofileandhighrefractiveindexofthefibercore,amicroextrinsicfiber-opticFabryProtinterferometric(MEFPI)strainsensorisfabricatedthroughchemicaletchingandfusionsplicing.Higherreflectanceofthemicrocavityisobtainedduetotheless-curvedinnerwallinthecenterofthefibercoreafteretchingandhigherindexcontrastbetweentheGI-MMFcoreandair.Themaximumreflectionofthesensorisenhanced12dBthanthatobtainedbyetchingoftheEr-orB-dopedfibers.Highfringecontrastof22dBisobtained.ThestrainandtemperatureresponsesoftheMEFPIsensorsareinvestigatedinthisexperiment.Goodlinearityandhighsensitivityareachieved,withwavelength-strainandwavelength-temperaturesensitivitiesof7.82pm/μεand5.01pm/°C,respectively.
简介:机载光电侦察吊舱为各类侦察应用提供了数据保障,应用需求也从传统的可见光/红外目标跟踪、有源定位、地理跟踪、火炮校射发展到无源定位,并进一步拓展到辅助着舰/着陆、广域探测、多目标记忆跟踪、机器学习与目标智能识别、视觉辅助导航等多项应用领域,机载光电侦察吊舱已经成为了一种高度集成的目标深度侦察工具。对上述应用领域的相关技术现状和发展进行了归纳和总结,指出并分析了当前机载光电侦察吊舱综合信息处理技术领域存在的主要突出问题,包括海量数据与计算资源有限的矛盾、多传感器综合应用深度尚浅、综合信息的误差分析及仿真评估不充分,而未来综合信息处理技术应朝着智能化、标准化和工程化等方向发展,才能有效提高情报搜集和处理效率,进而充分挖掘出机载光电侦察吊舱的应用潜力。