中文摘要：

TDLAS（可调谐半导体激光吸收光谱）技术以其分子光谱高选择性、速度快、灵敏度高、非接触测量等难以取代的优势，成为燃烧过程诊断等应用的首选，可以有效用于氧气测量。DFB（分布反馈）半导体激光器以其体积小、功耗低、寿命长、线宽窄、波长可调谐等优点成为 TDLAS 系统的主要选择，而其调谐特性是制约系统测量性能的关键因素。根据 TDLAS 氧气测量系统工作要求，采用一种简单易行的实验方法对系统中用到的764 nm DFB 激光器的电流波长、温度波长和电流功率等重要调谐特性进行了测试和分析，发现出射光谱窄线宽、高边模抑制比和宽波长可调谐范围等特点明显，电流波长调谐曲线近似但并非严格线性、调谐速率约0．023 nm·mA－1，温度越高阈值电流越大、PI 曲线也并非严格线性，温度调谐特性曲线线性较好、波长温度调谐速率基本保持恒定约为0．056 nm·℃－1。可见各种调谐曲线的非线性失真比较明显，影响氧气测量精度。温度调谐非线性可以通过温控精度的提高来消除，电流功率调谐非线性可以通过设置参考光强来消除。为了进一步解决电流波长调谐非线性问题，根据 DFB 半导体激光器的调谐机理和电流波长测试结果的多项式拟合，考虑通过 DA 控制注入电流的方式对电流波长调谐非线性进行补偿。这种方法针对不同激光器只需在系统初次工作之前进行一次多项式拟合，方案合理、实现简单且不影响测量过程。实验证明，补偿之后的λI 曲线线性拟合残差小于1 pm，远小于补偿前的22 pm，效果明显，为氧气各种参数 TD-LAS 精确测量和反演提供了依据。

英文摘要：

TDLAS （tunable diode laser absorption spectroscopy）technology,with its unmatched advantages such as high selec-tivity molecular spectra,fast response,high sensitivity,non-contact measuring,become the preferred scheme for combustion process diagnosis,and can be effectively used for oxygen measuring.DFB （distributed feedback）laser diode with its small size, low power consumption,long service life,narrow linewidth,tunable wavelength has become the main choice of the TDLAS sys-tem.Performance of laser tuning characteristics is a key factor restricting TDLAS’s measuring performance.According to TD-LAS oxygen measuring system’s working requirements,a simple experimental method was used to test and analyze tuning char-acteristics such as wavelength current,power current and wavelength temperature of a 764 nm DFB laser diode in the system. Nonlinear distortion of tuning curves was obvious,which affects oxygen measuring accuracy.The laser spectra’s characteristics such as narrow linewidth,high side mode suppression ratio and wide wavelength tuning range are obvious,while its wavelength-current tuning curve with a tuning rate of about 0.023 nm·mA-1 is not strictly linear.The higher the temperature the greater the threshold current,the PI curve is not strictly linear either.Temperature tuning curve is of good linearity,temperature-wave-length tuning rate keeps constant of about 0.056 nm/DEG C.Temperature tuning nonlinearity can be improved by high tempera-ture control accuracy,and current power nonlinearity can be improved by setting the reference light path.In order to solve the wavelength current tuning nonlinear problems,the method of DA controlling injection current was considered to compensate for non-linear wavelength current tuning according to DFB laser diode tuning mechanism and polynomial fitting of test results.In view of different type of lasers,this method needs only one polynomial fitting process before the system’s initial work.The com-pensation scheme is reasonable and the realization is sim