中文摘要：

光学薄膜吸收损耗的绝对测量对光学薄膜的优化设计与应用至关重要，以光热失调技术实现光学薄膜吸收损耗的绝对测量为研究目的，采取连续激光加热的方式，理论与实验相结合，提出了一种利用反射率或透射率、温度变化和加热光功率之间的3个线性关系，实现吸收损耗绝对测量的方法。针对设计的高反射光学薄膜实验样品，获得样品对加热光功率的吸收率绝对值为1．64×10^-2，并分析了影响测量精度的主要因素。研究表明，提出的方法可以实现光学薄膜吸收损耗的绝对测量，特别适合于具有较大反射率或透射率温度系数的样品，测量准确性依赖于样品表面温度理论模型的建立和实验测量的精度，研究结果为光热失调技术的进一步应用提供了理论和实验支持。

英文摘要：

The accurate measurement of absorption loss is very important in optimal design of optical thin films. In order to achieve absolute absorption measurement of the optical coating by photothermal detuning technique, a method was proposed according to theory and experiment with a continuous-wave modulated laser beam excitation, which utilized linear relationship between the reflectance（transmittance）, temperature rise, and heating laser power. The absolute absorption 1.64x10-2 of the test samples was obtained successfully by the proposed method. Main factors affecting the measurement precision were analyzed. The results show that the absolute absorption loss measurement of the optical coatings can be achieved by the proposed method. The method is particularly suitable for samples with large temperature coefficient of reflectivity or transmission. The accuracy of the method depends on the theoretical model of the sample surface temperature and the measurement accuracy of the experiment. The results provide a theoretical and experimental support for the further application of the photothermal detuning technique.