共查询到17条相似文献,搜索用时 103 毫秒
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为解决1 fJ~1 pJ脉冲激光能量的测量问题,提出了一种基于时域波形积分的飞焦级脉冲激光能量测量方法。该方法采用光电倍增管(PMT)获得飞焦级脉冲激光的响应信号,该微弱响应信号经放大、校准与激光脉冲时域波形积分后实现飞焦级脉冲激光能量测量。根据该方法设计了飞焦级脉冲激光能量测量装置,并分析了该装置的测量不确定度。实验表明,该装置实现了波长1 064 nm、脉冲宽度5 ns~1 s、能量范围1 fJ~1 pJ的脉冲激光光源的能量测量,测量不确定度为15.8%。 相似文献
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热释电红外探测器的原理与特性 总被引:2,自引:0,他引:2
热释电红外探测器简称热释电探测器,是近十年来在热探测领域得到重要发展的一种新型热探测器.据报道这种探测器可以广泛地用于辐射温度测量、红外光谱测量、激光参数测量、非接触式温度测量、工业过程自动监控、安全警戒、红外摄象与空间技术等方面.我国在这方面的研究,虽然起步晚些,但近来也有重要研究成果报道.这种探测器和以往常用的测辐射热计、温差热电堆、高莱探测器等热探测器比较,具有以下特点: (1)频率特性好.其他热探测器都是在热平衡后输出最大,工作时辐照时间必须大于热平衡的时间常数(一般为数毫秒至数十毫秒).而热释电探测器,… 相似文献
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激光脉冲加热下含湿多孔介质温湿信号的测量与分析 总被引:2,自引:0,他引:2
本文介绍了一种动态测量激光脉冲加热下多孔介质温湿信号变化的方法。借助于响应时间为1μs的超小型薄膜电阻及日本 YOKOGAWA DL2700数字示波器,研制了能对激光脉冲加热下多孔介质温湿信号的变化迅速作出响应的测量系统。利用可编程NdYAG激光发生器触发高能流密度的小尺寸短脉冲激光,轰击有高空隙率及热延迟时间为秒量级的纸张,进行测定多孔介质温湿信号变化的实验。通过实验发现,在该测量系统下可观测到明显的湿纸张温度信号的阶跃与波动效应以及湿份信号的突变特征。信号洁净、干扰小、信噪比高,信号有良好的跟随性,从而为研究多孔介质超急速传热传质过程中热质的传递行为提供实验测量手段。 相似文献
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利用斩波器将连续激光斩波成为脉冲宽度s量级重频脉冲激光,利用选单器将重频脉冲激光转变成单脉冲激光,从而实现变连续激光为单脉冲激光。由陷阱探测器测量连续激光的输出功率,高速APD、高增益PIN探测器作为波形探测器测量脉冲激光波形,并通过示波器对脉冲宽度进行测量。依据测量得到的功率和波形就可得到脉冲激光能量,从而实现了0.2 pJ激光微能量的测量和校准,通过不确定度分析,该装置的pJ激光能量测量不确定度达到了0.42%。 相似文献
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用于脉冲n/γ混合场γ强度测量的ICI探测器 总被引:2,自引:0,他引:2
研制成功一种基于康普顿效应, 用于脉冲裂变n/γ混合场γ强度绝对测量的新型辐射探测器—ICI(绝缘体-导体-绝缘体)探测器. 除具有现有真空康普顿和介质康普顿探测器时间响应快、线性电流大、抗辐射干扰能力强等优点外,该探测器从结构上抑制了真空康普顿在快脉冲γ测量中的前后负冲信号, 并且工作时不需要高真空, 而γ灵敏度却与同尺寸介质康普顿探测器相当. 由于其探测灵敏介质厚度小于2mm, 因而在群脉冲辐射探测中, 不会显著影响后续和周围探测器的
测量环境, 是一种探测脉冲γ射线较理想的探测器. 相似文献
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为了得到具有平坦光谱响应的辐射探测器,1963年,Eisenman提出了锥腔型探测器[1].1966年,Scott把锥腔型探测器用于激光的测量[2],并在此后得到推广.由于激光入射在锥腔探测器接收面不同位置时,其响应度不同(即所谓接收面响应不均匀),致使激光脉冲能量测量及标定过程中出现的误差 相似文献
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The transient response characteristics of HgCdTe photoconductive detector under the radiation of ultra-short laser pulse have been discussed in detail. Specifically, the transient effect of pulse width to the temperature of electronics and crystal lattice, and corresponding resistance changes of detector are mainly discussed. Based on traditional drift-diffusion model, considering that the temperature of electronics and crystal lattice are different under the ultra-short laser pulse, the double-temperature equation is joined to describe the semiconductor carriers’ dynamics features. Using the numerical method, the transient response characteristics of detector in the case of ultra-short pulse have been worked out. The calculation results show that: When the pulse width is greater than nanosecond pulse, the temperature of electronics will be equal to which of crystal lattice. If the pulse width is less than nanosecond pulse, the temperature of electronics is higher than which of the latter. After the end of a pulse, the rebound resistance of detector will be higher than the dark resistance because of the thermal effect. The heat effect is more obvious when a pulse with narrower width and higher energy density incident to the detector. 相似文献
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Gao Xiang 《International Journal of Infrared and Millimeter Waves》1990,11(5):641-649
In this paper, the application of the pyroelectric detectors for Far-Infrared laser diagnostics on TOKAMAK plasma is described. We discovered experimentally that the Fabry-Perot interference could affect the performance of the pyroelectric detectors (PED). The improved pyroelectric detector (IPD) was developed for FIR laser coheront measuring. Some designing considerations about the pyroelectric detectors used in high temperature plasma conditions are mentioned. 相似文献
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V. M. Aptin L. M. Dorozhkin G. N. Makarov G. M. Pleshkov 《Applied physics. B, Lasers and optics》1982,29(4):273-278
A pyroelectric detector with a time resolution of 3–5 s and a TEA CO2 laser have been used in diagnostics of a pulsed molecular beam (a free jet). The kinetic energy distribution of molecules was determined by using time-of-flight measurements both with a laser and without it. A combination of the laser with the pyroelectric detector makes it possible to determine the kinetic energy distribution of molecules in a selected internal state and to measure the energy absorted by the molecules of the beam from a laser pulse. The results obtained for pure SF6 and the SF6 seeded in He have been presented and analyzed. The advantages and the disadvantages of the method are being discussed in comparison with other available methods of diagnostics of molecular beams and free jets. 相似文献
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脉冲串互相关方法在远程激光测距中的应用 总被引:1,自引:0,他引:1
基于单脉冲激光测距在远程激光测距中的局限性,提出了一种基于发射脉冲串与回波脉冲串互相关的信号处理方法。该方法将多个激光发射脉冲和回波脉冲作为一次连续信号同时数字化,然后进行互相关处理。采用激光强度与发射间隔可调的激光系统来模拟不同反射强度、不同距离的测距回波信号;通过处理不同信噪比的回波信号,来探究本方法对于回波信号信噪比的提升能力以及对于尖峰噪声的抑制能力。实验结果表明,该方法能够有效提高回波信号的信噪比,信噪比为0.11的弱回波信号经过处理后信噪比被提升到5.92,从而扩展了激光测距系统的测程,有效降低了探测系统的探测虚警率,提高了远程激光测距系统的弱回波探测能力。 相似文献