大气气溶胶粒子吸收对地球辐射收支平衡、激光在大气中的传输等具有重要影响, 其吸收特性的准确测量越来越受到重视。介绍了气溶胶吸收系数的光热干涉法的测量原理、解调算法与标定原理。通过搭建的全光纤结构光热干涉实验装置, 对N2、NO2和含碳气溶胶进行了定性测量, 利用NO2气体在532 nm波段的吸收实现了实验装置的初步标定, 获得目前装置对NO2气体的最小可探测浓度为3.976 mg·m-3。分析结果表明光热干涉法在实际大气气溶胶粒子吸收特性的测量上潜力巨大。

The absorption of atmospheric aerosol particle affects earth′s radiation balance and laser transmission in atmosphere, especially high energy laser. The precise measurement of aerosol light absorption is paid more and more attention. The basic principles of the photo-thermal interferometry for measuring aerosol absorption coefficient, demodulation algorithms and calibration principle were introduced. A fiber structure photo-thermal interferometer instrument was developed, and the feasibility was verified by measuring the absorption of N2, NO2 and black carbon aerosol. Finally, quantitative analysis was executed with the standard NO2 gas at 532 nm whose detection limitation was 3.976 mg·m-3. The qualitative and quantitative analysis demonstrate that the fiber structure photo-thermal interferometer has great potential in practical aerosol absorption measurement.