【作者】 王晨；

【导师】 方晓东；

【作者基本信息】 中国科学技术大学 ， 精密仪器及机械， 2021， 硕士

【摘要】 激光凭借着其能量高、方向性好、相干性以及单色性好等特殊物理性能在各种重大工业设备、雷达、武器、通讯以及物理实验中广泛应用。激光技术的快速发展,同时也推动了重大科学装置及工程、自动化测试实验、精密光电设备等领域的进步。在这些大型高精度设备中,由于整机系统的功能多样且复杂,运行时各部件之间对于时间的精度要求较高,单路激光触发的局限性愈加明显。因此,通常采用多路激光的方案进行同步触发来保证设备中各部件的触发精度,其中,主要包括延时精度、抖动、上升沿、抗干扰性等参数的要求。另外,在高能物理等测量实验中,多路激光同步触发系统可为不同设备提供一个多种类的同步时标基准信号,是触发多台测试仪器的一种极为有力的工具。针对多路复杂激光系统的实际需求以及国内研究不足的现状,本文开展了高精度多路激光同步触发的系统设计和关键性技术研究。本文主要研究内容包括:1.首先研究了高精度延时的控制方法,设计了基于PLL锁相环移相的延时技术,实现了一个时钟周期内的精细调节,调节精度≤1ns;系统搭配专用的延时芯片和外围电路最终实现调节步进1Ops。精密延时模块在电气结构上与外界进行隔离,性能稳定且控制简单。2.其次研究了光电信号的快速采样电路和信号分析方法,设计了同步逻辑电路和时间检测电路,系统基于时序判断结果或者时间差值数据实现了延时时间的自动反馈调节。3.接着研究了两种人机交互模式,设计了基于PC端的LabVIEW控制软件和基于嵌入式的触摸屏控制系统,实现了参数配置及显示、系统切换等功能。操作系统移植性强,且方便灵活、操作性好、占用空间少。4.最终探究了多路激光同步触发系统的整机性能以及MOPA准分子激光装置的脉冲能量放大特性。同步触发系统可实现调节分辨率达10ps;延时及脉宽调节范围0～325μ外触发抖动<±2.5ns,同步抖动<60ps;上升沿时间<1.1ns,下降沿时间<1.4ns;电压调节范围1.5～15V。利用该系统与MOPA结构准分子激光装置进行联动测试,实现了双腔放电时序抖动小于±ns;并探究了重复频率对输出脉冲能量的影响;整机系统放电延时准确度高,在4kHz的高重频下,通过控制延时间成功获得种子腔的脉冲放大,获得了双腔最大放大率19.19,最大输出脉冲能量7.1mJ;最后,在双腔放电时序的闭环控制中,实现了延时时间的自动反馈调节。本文采用PLL锁相环移相技术以及专用延时芯片,设计了高分辨率的多路激光同步触发系统。系统在复杂的电磁干扰环境下实现了长期稳定运行以及实时控制;同时具有光电信号的快速采样、时间检测与逻辑判断能力,可实现系统的自动反馈调节,在高精度脉冲测试以及多路激光的复杂系统等领域具有一定的参考价值。更多还原

【Abstract】 Lasers are widely used in various major industrial equipment,radars,weapons,communications,and physical experiments due to their special physical properties such as high energy,good directionality,coherence,and good monochromaticity.The rapid development of laser technology has also promoted the progress of major scientific devices and engineering,automated test experiments,and precision optoelectronic equipment.In large precision equipment,due to the diverse and complex functions of the entire system,the requirements for time accuracy between various components during operation are relatively high,and the limitations of single-channel laser triggering are becoming more and more obvious.Therefore,a multi-channel laser scheme is usually used for synchronous triggering to ensure the trigger accuracy of each component in the device,which mainly includes the requirements of delay accuracy,jitter,rising edge,anti-interference and other parameters.In addition,in high-energy physics and other measurement experiments,the multi-channel laser synchronous trigger system can provide a variety of synchronous time-scale reference signals for different devices,and it is an extremely powerful tool for triggering multiple test instruments.Aiming at the actual needs of multi-channel complex laser systems and the current status of insufficient domestic research,this paper has carried out the system design and key technology research of high-precision multi-channel laser synchronous triggering.The main research contents of this paper include:1.First study the high-precision delay control method,design the delay technology based on the PLL phase-locked loop phase shift,realize the fine adjustment within one clock cycle,the adjustment accuracy is≤Ins;The system is equipped with a dedicated delay chip and peripheral circuits to finally achieve an adjustment step of 10ps.The precision delay module is electrically isolated from the outside world,with stable performance and simple control.2.Secondly,the photoelectric signal fast sampling circuit and signal analysis method are studied,and the synchronous logic circuit and time detection circuit are designed.The system realizes the automatic feedback adjustment of the delay time based on the timing judgment result or the time difference data.3.Then two human-computer interaction modes are studied,and the PC-based LabVIEW control software and the embedded-based touch screen control system are designed to realize parameter configuration and display,system switching and other functions.The operating system has strong portability,is convenient and flexible,has good operability,and takes up less space.4.Finally,the overall performance of the multi-channel laser synchronous trigger system and the pulse energy amplification characteristics of the MOPA excimer laser device are explored.The synchronization trigger system can achieve an adjustment resolution of 10ps;delay and pulse width adjustment range 0～325μs;external trigger jitter<±3ns,synchronization jitter<60ps;rising edge time<1.1ns,falling edge time<1.4ns;voltage adjustment range 1.5～15V.Using this system and MOPA structure excimer laser device to carry out linkage test,realized the dual-cavity discharge timing jitter less than±3ns;and explored the effect of repetition frequency on the output pulse energy;High accuracy of discharge delay of the whole system.Under the high repetition frequency of 4kHz,the pulse amplification of the seed cavity is successfully obtained by controlling the delay time,and the maximum amplification rate of the dual cavity is 19.19 and the maximum output pulse energy is 7.1mJ;Finally,in the closed-loop control of the dual-cavity discharge sequence,the automatic feedback adjustment of the delay time is realized.This article uses PLL phase-locked loop phase-shifting technology and a dedicated delay chip to design a high-resolution multi-channel laser synchronous trigger system.The system has achieved long-term stable operation and real-time control in a complex electromagnetic interference environment;At the same time,it has the ability of fast sampling of photoelectric signals,time detection and logic judgment,and can realize automatic feedback adjustment of the system.It has certain reference value in the fields of high-precision pulse testing and complex systems of multiple lasers.更多还原