基于ADuC842的高精度激光器驱动器设计与研究

发布时间：2018-04-18 23:35

本文选题：半导体激光器 + 电流驱动　；参考：《华中科技大学》2015年硕士论文

【摘要】：半导体激光器具有单色性、相干性好,准直度高,强度大,能耗小,效率高等优点,令其在军事,医疗,通信等领域发挥着无可替代的作用。然而它对工作电流和温度极为敏感,电流的起伏不仅会引发激光器的噪声,还会造成光波长的改变,同时工作时产生的热量还会增大其阈值电流,降低其寿命,此外浪涌、静电等诸多干扰还会击穿激光器的PN结。为了确保激光器能够稳定可靠的工作,研制出一种体积小,高稳定度,无浪涌电流,电流连续可调,温度可控的激光驱动器具有比较重大的现实意义。本论文首先分析了半导体激光器的工作原理、特性和损坏机理,在此基础上制定了本论文工作目标,确定了系统方案设计。然后根据方案,设计了具有恒流驱动和温控的半导体激光器驱动系统。驱动系统中,根据按键输入的目标值转为单片机DAC电压输出,经过恒流源的电压-电流转换从而驱动激光器,内部由PID算法进行电流调整;温控系统中,通过控制驱动芯片稳定温度,最终保证温度恒定;此外还设计了各种保护电路。文章最后对系统性能进行了测试和分析。对PID进行了仿真,其电路符合对温控模块的基本需求。对电流精度以及电流、温度和长期稳定性做了大量的实验测试,其精度和稳定度较高,满足系统预期目标。接着选用DFB激光器对系统进行实际验证,其光源输出稳定。因此可最终得出,此系统性能良好,基本达到设计目标,可以满足激光驱动的基本功能。
[Abstract]:Semiconductor lasers have the advantages of monochromatic, good coherence, high collimation, high intensity, low energy consumption and high efficiency, which make them play an irreplaceable role in military, medical, communication and other fields.However, it is extremely sensitive to the working current and temperature. The fluctuation of the current not only causes the noise of the laser, but also changes the wavelength of the light. At the same time, the heat generated during the operation also increases its threshold current, reduces its life, and the surge.Static electricity and many other interference will also break down the PN junction of the laser.In order to ensure that the laser can work stably and reliably, it is of great practical significance to develop a laser driver with small volume, high stability, no surge current, continuously adjustable current and controllable temperature.In this paper, the working principle, characteristics and damage mechanism of semiconductor laser are analyzed firstly, and then the working goal of this thesis is established, and the system scheme design is determined.Then, a semiconductor laser drive system with constant current drive and temperature control is designed according to the scheme.In the driving system, according to the target value input by the keystroke, the output of the DAC voltage is converted into the output of the single-chip microcomputer. The laser is driven by the voltage-current conversion of the constant current source, and the internal current is adjusted by the PID algorithm.By controlling the driving chip to stabilize the temperature, the temperature is kept constant, and various protection circuits are designed.Finally, the performance of the system is tested and analyzed.The simulation of PID is carried out, and its circuit meets the basic requirement of temperature control module.A large number of experiments have been carried out on the accuracy of current, current, temperature and long-term stability. The accuracy and stability of the experiment are high and meet the expected goal of the system.Then the DFB laser is used to verify the system, and the output of the light source is stable.Therefore, it can be concluded that the system has good performance, basically achieves the design goal, and can satisfy the basic function of laser drive.
【学位授予单位】：华中科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TN248

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