大气气溶胶粒子吸收虽然一般比较微弱，但对地球辐射收支平衡、高能激光在大气中的传输具有重要影响，因而该吸收特性的准确测量越来越受到重视。针对光热测量技术，通过分析气溶胶因吸收激励激光能量产生的温度分布和折射率变化，给出了光热干涉的相位变化量与有效吸收系数、作用时间的关系；阐述了利用相位载波(PGC)算法获得相位变化信息的方式；以强、中、弱3种吸收特性的气溶胶为例，说明了不同激励激光波长下的光热效应；通过仿真计算及误差分析，展示了PGC 算法在解调精度和抗噪上的优势；对解调算法进行了初步的实验验证。

The absorption of atmospheric aerosol particle is weak, but it affects earth′s radiation balance and atmospheric high energy laser transfer, so its precise measurement is paid more and more attention. By the analysis alteration of temperature distribution and refractive index which induced by pumping laser, the relationship of photo-thermal phase, effective absorption coefficient and excited time is deduced. Then phase generated carrier (PGC) algorithms for measuring phase change information is declared. It is also calculated that several photothermal effect of three typical aerosols with different absorbing capabilities which irradiated by pumping laser at two wavelengths. Then, the superiority of PGC algorithms is displayed, including its demodulation precision and noise elimination with calculation and error analysis. The experimental research of PGC algorithms is done.