共查询到18条相似文献,搜索用时 125 毫秒
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高功率高重频TEA CO_2激光器均匀场放电电极设计 总被引:2,自引:0,他引:2
介绍了在高功率、高重频TEACO2激光器上应用的修整改型Chang氏电极的结构形状。对修整改型的Chang氏电极在垂直放电方向上有较好的均匀性、电极的曲面、电极表面电场强度分布、主放电极辉光放电和放电区域均匀放电做了必要的论述。通过电极型面及结构的基本放电参数与输出特性的实验,并结合在大功率、高重频、高脉冲能量和高速气体循环特点下的TEACO2激光器,说明选择修整改型后的Chang氏电极更为适宜。 相似文献
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本文报告高功率紫外光预电离ArF准分子激光器的实验研究。使用F_2+Ar+He混合气体作为工作介质,已获得ArF最大脉冲激光能量219毫焦耳,总效率0.5%左右。本器件并可输出KrF激光,最大脉冲激光能量424毫焦耳,总效率约1%。激光器是由内径为8.4cm的玻璃钢圆筒做成,长94cm。电极采用张氏均匀场型面电极,电极有效平区宽5mm,电极长80cm,两电极之间距离为2.1cm,因此激活体积为80×2.1×0.5cm~3。放电采用LC反转电路,主放电电容为平板电容,电容量分别为C_1=12nF和C_2= 相似文献
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近几年来,横向激励大气压脉冲CO_2激光器在国内外引起了广泛的注意。为了增加这类激光器的输出,提高转换效率,许多科学工作者已经并正在许多方面进行理论和实验方面的研究。除了在激发方式、电极构造和改进放电性能等方面取得了一系列的进展之外,还发现在激光器中加入适量的氢气,将有助于均匀放电,从而可进一步地提高输入能量,相应地增加输出能量。我们对氢气在双放电的绕丝状电极激光器中的作用进行了实验。实验的结果示于图1至图4。其输出能量均作归一化处理。图1~3说明了在不同的输入能量和气体比的情况下,氢气在激光器中所起的作用。 相似文献
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为获取得高能脉冲中红外激光,对两种形式的电引发非链式脉冲DF化学激光器进行了研究。通过研究紫外预电离自持放电非链式脉冲DF化学激光器的输出特性,确定了最佳气压比,实现了350 mJ的DF激光脉冲输出,激光峰值功率为1.4 MW,激光能量比输出达35 J/l.101.3 kPa,电光转换效率约为1.6%;为突破预电离条件的限制,研究了非链式脉冲DF化学激光器的自引发体放电特性,通过采用针-盘电极对放电来模拟单通道放电的过程,利用非均匀场粗糙表面阴极,在注入能量密度高达200 J/l时实现了无预电离的稳定体放电。实验结果表明,采用自引发体放电技术有望实现更高能量的中红外激光输出。 相似文献
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为了研究脉冲CO2激光诱导空气放电的特性,建立了高压电容充放电实验平台,采用间距为8mm、半径为10mm的一对球形石墨电极,取得了放电电压和电流的实时数据,采用2阶振荡电路模型对放电电压和放电电流进行拟合得到了电极间激光诱导放电等离子体的阻抗,并对放电时间、放电延时及抖动做了统计。结果表明,激光诱导放电等离子体的阻抗很小,约1Ω~2Ω,拟合得到的放电等离子体阻抗随放电电压、放电电容、以及激光能量的增加而减小;放电延时随着实验条件的变化在2μs~10μs之间变化,放电延时以及延时抖动随着放电电压和激光能量的增加而降低,而受放电电容大小的影响不明显。由此高稳定性的激光脉冲和高压有助于激光诱导放电过程的稳定。 相似文献
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紫外预电离TEA CO2激光器的实验研究 总被引:1,自引:0,他引:1
介绍了采用火花针紫外预电离高重复频率TEA CO2激光器系统的结构及其实验研究结果.该激光器的脉冲放电行为由旋转火花开关和高压脉冲触发器进行控制,并通过自动翻转电路实现对称张氏电极之间的均匀辉光放电.通过改变激光器工作气体气压、充气配比及注入能量,测量单脉冲输出能量.实验结果表明,激光器的输出能量及电光转换效率随CO2或N2充气压改变存在最佳点,最佳点与注入能量有关.输出能量及电光转换效率与总充气压呈线性关系.该激光器在单脉冲放电条件下比在高重复频率时能够注入更多的能量和充入更高的气压,脉冲能量最大输出可达53J以上,经过进一步地参数优化,该激光器最高的电光转换效率达到17%以上. 相似文献
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顺序放电高重复频率TEA CO2激光器 总被引:2,自引:0,他引:2
研制了一台高重复频率顺序放电TEA CO2激光器,由共用光学谐振腔的两节相同放电组件组成,单组件的有效增益体积为2.5 cm×2.5 cm×55 cm.激光器允许以不同的双脉冲时间间隔和不同的脉冲重复频率工作并产生高峰值功率输出双脉冲.当两组件以200 Hz重复频率同步放电时,激光器输出平均功率为1.1 kW;当两组件以400 Hz重复频率顺序放电时,输出平均功率为550 W,双脉冲时间间隔为2.5 ms.在同一脉冲重复频率下,激光器的平均输出功率随双脉冲间隔的增大而减小.实验还测量了不同双脉冲间隔下,激光器的输出双脉冲波形. 相似文献
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Kun-Ming Lee Chern-Lin Chen Shin-Tai Lo 《Industrial Electronics, IEEE Transactions on》2003,50(3):554-559
This paper proposes the use of a resonant pole inverter (RPI) as the control circuit to drive the data electrodes of an ac plasma display panel (PDP). This new application of RPI simplifies the circuit design by using fewer components, and has lower power losses than conventional driver circuits. The circuit employs two resonant MOSFETs and zero-voltage-switching technique to generate an asymmetric pulse train with moderate rising and falling time to drive the data electrodes of a PDP. The circuit also recovers the reactive energy from the PDP, like conventional energy recovery circuits. Power losses are further reduced by adding a dc offset voltage to the pulse train. The power consumptions of different driving circuits are assessed. The proposed circuit is tested on a dual-scan 42-in SVGA ac plasma display panel and is found to be practical. 相似文献
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Perceived locus and intensity of electrocutaneous stimulation 总被引:1,自引:0,他引:1
Two experiments investigated perceived locus and intensity for electrocutaneous stimulation. In Experiment 1, 21 subjects reported the perceived locus for various combinations of four electrode sites, two current directions, two pulse characteristics (single versus multiple), and two sensation levels (detection versus pain). In Experiment 2, 16 subjects reported the perceived locus and intensity for a wide range of current levels and two polarity conditions. The main results were 1) sensations were likely to be perceived under the cathode at detection levels, but under both electrodes at intense levels; 2) the "cathode" localization was gradually supplanted by "both" ("anode" and "cathode") localization with increasing current; 3) subjective intensity under the cathode was greater than that under the anode; 4) the effects of cathode position on perceived locus were found for only some pairs of electrodes. These results challenge the simple hypothesis that electrical stimulation of the skin through paired electrodes is perceived under the cathode. 相似文献
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为了探讨光纤中五阶非线性下不同形状光脉冲对的交叉相位调制特性,从包含五阶非线性效应的扩展耦合非线性薛定谔方程组出发,导出了不同形状光脉冲对的非线性相移和频率啁啾公式。计算并比较了它们的相移、啁啾和功率频谱。结果表明,较强的负五阶非线性对相移、啁啾和频谱曲线中心附近的形状有较大的影响,而正五阶(较弱的负五阶)非线性则只使相移和啁啾量增大(减小),使频谱变宽(变窄)、谱峰变多(变少)。孤子对和高斯对的谱形相似,随五阶非线性系数的不同,能量最强的谱峰可能在中央附近也可能在最边缘处。各阶超高斯对的谱形也相似,但能量大部分集中在中央峰处。研究对光脉冲压缩、光开关器件和光纤通信系统性能的提高等有一定的意义。 相似文献
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《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》1973,61(12):1766-1767
A pulse pair waveform can be transmitted in order to estimate the mean of the wake velocity power spectrum at a given range sampling station of an object reentering the atmosphere. It is shown here how one may select the spacing between pulses in a pair so as to minimize the predicted variance of the mean velocity estimate. This variance is a function of the radar wavelength, the pulse signal-to-noise ratio, and the true spread of the wake power spectrum to be measured. These parameters are all assumed known a priori or available from previous data. For a given wavelength and power spectrum, the optimum pulse pair spacing to be used depends only on the signal-to-noise ratio and not on the number of pairs. Therefore, one can simply send, at the optimum spacing, the fewest pulse pairs required to achieve the necessary accuracy and thus minimize the radar energy required as well. 相似文献