高精度光电检测系统的研制

发布时间：2018-01-25 00:42

本文关键词： 光电检测光电倍增管模块电流放大器蓝宝石底座 EAST　出处：《合肥工业大学》2017年硕士论文　论文类型：学位论文

【摘要】：光电检测系统是光电检测设备的重要组成部分,主要由光电探测器和电流放大器两部分构成。光电探测器将待测光信号转化为电流信号,电流放大器将探测器输出的电流信号转化为电压信号并进行放大。为了完成对比较微弱且持续时间较短的光信号的精确测量,在设计过程中需要权衡光电检测系统的增益、带宽和噪声。本文调研了国内外光电检测系统的研究现状,详细分析了其工作原理、组成器件和设计难点,设计出精度较高的光电检测系统。系统选用光电倍增管(PMT)作为光电探测器,相比于其他光电探测器,其具有超高的内部增益、较高的灵敏度和较短的响应时间等特性。电流放大器由前置放大器和电压放大器构成,其中前置放大器的设计是难点。分别采用印刷电路板(PCB)和蓝宝石材料作为电流放大器的基板,探究两种材料对电路的影响并在实验室做了对比测试。当电流放大器(增益为106V/A)输入端短接后,两种基板电路输出噪声峰峰值大约为3mV。另外,在无光信号输入的情况下,保持光电检测系统的整体增益和带宽不变,测量了不同增益配比下的输出噪声。当PMT模块的控制电压为0.49V,基于蓝宝石底座的电流放大器增益为2×105V/A时,系统输出噪声较低,峰峰值大约为4.56 mV。2016年冬季,该光电检测系统在先进实验托卡马克(EAST)装置的filterscope诊断系统中得以测试。实验数据表明,该光电检测系统能够检测到不同频率的边缘局域模(ELM)事件以及频率在~kHz量级的边际震荡,为准确研究ELM行为和H-mode等离子体提供帮助。
[Abstract]:Photoelectric detection system is an important part of photoelectric detection equipment, mainly composed of two parts: photoelectric detector and current amplifier. The photoelectric detector converts the light signal to current signal. The current amplifier converts the current signal from the detector into a voltage signal and amplifies it. In the process of design, we need to weigh the gain, bandwidth and noise of the photoelectric detection system. This paper investigates the research status of photoelectric detection system at home and abroad, analyzes its working principle, components and design difficulties in detail. A photoelectric detection system with high precision is designed. PMTs are used as photodetectors. Compared with other photodetectors, PMTs have super-high internal gain. High sensitivity and short response time. The current amplifier consists of a preamplifier and a voltage amplifier. The design of preamplifier is difficult. PCB (printed circuit board) and sapphire are used as the substrate of current amplifier. The effects of the two materials on the circuit were investigated and tested in the laboratory when the current amplifier (gain 106V / A) input was short-connected. The peak output noise peak of the two substrates is about 3 MV. In addition, the overall gain and bandwidth of the photoelectric detection system are kept unchanged without light input. When the control voltage of PMT module is 0.49V and the gain of current amplifier based on sapphire base is 2 脳 105V / A, the output noise of the system is low. The peak value is about 4.56 mV.2016 in winter. The photoelectric detection system has been tested in the filterscope diagnostic system of the advanced experimental Tokamak EAST device. The photoelectric detection system can detect edge local mode (ELM) events with different frequencies and marginal oscillations of frequency in the order of kHz. It is helpful for the accurate study of ELM behavior and H-mode plasma.
【学位授予单位】：合肥工业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN15

【参考文献】