X光条纹相机扫描电路的研制

发布时间：2018-10-10 06:56

【摘要】：X射线条纹相机作为一种高时空分辨率的诊断设备被广泛应用于超快诊断领域。在激光聚变实验中,X射线携带有其中许多物理过程的重要信息;并且激光聚变实验时间尺度小(纳秒量级)、空间尺度小(百微米量级)。因此利用X射线条纹相机对X射线进行诊断显得尤为重要。随着实验的深入,需要更高性能的诊断设备来更加细致的分析激光聚变复杂的物理过程。扫描电路通过使电子束在垂直方向上随时间线性偏转,从而使条纹相机获得了将时间信息转换为空间信息存储的能力。提升扫描电压的斜率能够提高扫描速度,从而提高条纹相机的时间分辨率。此外,分析扫描电路的工作原理有助于条纹相机的适应性调整;分析扫描脉冲波形质量对测量结果的影响有利于误差分析。为了提升现有扫描电路性能,本文设计并制作了一个基于雪崩三极管的高速扫描电路,主要工作内容如下:1.分析了影响条纹相机时间分辨率的因素,指出提升扫描速度是最可能的提高时间分辨率的途径,而提升扫描速度依赖于提升扫描电压的斜率。2.建立了RLC等效电路,分析各个设计参数与扫描电压波形的关系。3.建立一维模型来描述雪崩三极管中因雪崩倍增效应而急速增长的电流引发二次击穿导通的过程。4.选取雪崩三极管ZetexFMMT417作为核心器件,设计制作了扫描电路,面积仅为现有扫描电路的一半。5.搭建测试平台。首先是利用示波器对制作的扫描电路的输出幅值、边沿、触发阈值、延迟进行测试,与现有扫描电路3 ns档比较,有两点明显改进:延迟降低了12 ns;降低了欠冲(或者过冲)的影响,消除了“回扫”问题。然后搭载条纹相机对扫描速度和扫描非线性进行了测试,取得了优秀的结果:扫描非线性为1.95%,扫描速度为61.4 ps/mm。
[Abstract]:X-ray stripe camera is widely used in the field of ultra-fast diagnosis as a high spatial-temporal resolution diagnostic equipment. In the laser fusion experiment, the X-ray carries many important information about the physical process, and the time scale of laser fusion experiment is small (nanosecond order) and the space scale is small (100 micron order of magnitude). So it is very important to use X-ray stripe camera to diagnose X-ray. With the development of the experiment, higher performance diagnostic equipment is needed to analyze the complicated physical process of laser fusion in more detail. The scanning circuit enables the stripe camera to gain the ability to convert time information into spatial information by making the electron beam deflection linearly with time in the vertical direction. Increasing the slope of the scan voltage can improve the scanning speed and improve the temporal resolution of the stripe camera. In addition, analyzing the working principle of the scanning circuit is helpful to the adaptive adjustment of the stripe camera, and the analysis of the effect of the quality of the scanning pulse waveform on the measurement results is beneficial to the error analysis. In order to improve the performance of the existing scanning circuit, a high-speed scanning circuit based on avalanche transistor is designed and fabricated in this paper. The main work is as follows: 1. The factors affecting the temporal resolution of the stripe camera are analyzed, and it is pointed out that raising the scanning speed is the most likely way to improve the temporal resolution, and the lifting speed depends on the slope of the rising scan voltage. The RLC equivalent circuit is established, and the relationship between each design parameter and the scan voltage waveform is analyzed. A one-dimensional model is established to describe the process of secondary breakdown induced by a rapidly increasing current in avalanche Triode due to avalanche multiplication effect. The ZetexFMMT417 of avalanche transistor is selected as the core device, and the scanning circuit is designed and fabricated. The area is only half of that of the existing scanning circuit. Build the test platform. First of all, the output amplitude, edge, trigger threshold and delay of the scan circuit are tested by oscilloscope, and compared with the existing scan circuit 3 ns file. There are two significant improvements: the delay reduces 12 ns; to reduce the undershoot (or overshoot) effect, eliminating the "backsweep" problem. Then the scanning speed and the scanning nonlinearity were tested with the stripe camera, and the excellent results were obtained: the scanning nonlinearity was 1.95 and the scanning speed was 61.4 ps/mm..
【学位授予单位】：电子科技大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TB852

【相似文献】