中文摘要：

本文报道导了对长脉冲工作模式下中心波长为1274cm^-1量子级联激光器光谱特性的研究结果．通过采用高带宽的中红外HgCdTe探测器及高速数据采集装置得以记录时域下的光谱，结合高分辨率的标准具，可以获得有关光谱在频域下的信息．通过对测量的光谱数据的分析，获得了光谱的外形、调谐特性、分辨率随时间变化的特性与规律，以及电压、温度对光谱的影响方式，得到了提高光谱分辨率、优化光谱质量的方法，从而可以提高下一步光谱定量分析的准确性．

英文摘要：

Mid-infrared lasers are very effective for the spectroscopic measuring of the fundamental absorption lines for most gases. The quantum cascade laser （QCL）, with the advantages of high power, wide tuning range and room-temperature operation, is one of the ideal mid-IR sources for trace gas detection. In this paper, the spectral characteristics of room temperature operated pulsed QCL with a cental wavelength of 1274 cm-1 is presented. By using high-bandwidth HgCdTe detector and high-speed data acquisition devices, and combining with a high-resolution etalon, the features of the spectrum in the frequency domain can be acquired. Analysis of the measured spectral data gives the information about spectral shape, tuning characteristics and resolution variation with time, also about the influences of voltage and temperature on spectrum. The effective way to improve the spectral resolution and optimize the spectral quality is obtained, and it can be used to improve the accuracy of spectrum quantitative analysis.