摘要

A new method has been proposed to obtain damage defect density in optical thin films from the differential coefficient of the damage probabilities with respect to the spot size. The retrieval method avoids utilizing the value of defect damage threshold which can't be measured directly. Firstly, the simulated damage probability curves under some certain irradiated laser fluences have been done by setting damage defect density as 5x10(3)/cm(2). Then, the differential coefficient of the damage probabilities with respect to the spot size is done from the simulated damage probability curves. Finally, the calculation of damage defect density has been done by the proposed method. The results show that the calculated defect density agrees well with the set value.