A time-resolved high-power laser photometer, which measures the real-time variations of transmission, internal reflection, and scattering simultaneously with picosecond time resolution, was developed to investigate the material response sequence during high-power nanosecond laser irradiation in thick fused silica. It was found that the transient transmission decreased sharply accompanied with an increase in internal reflection at the rising edge of the laser pulse. The transient transmission recovered while laser damage did not occur, but it did not recover if the scattering increased, indicating the occurrence of laser damage. The reason of sharp-decrease of transmission and the relationship between the transmission drop and laser damage were discussed.
cao zhen, He Hongbo, Hu Guohang, Zhao Yuanan, Yang Liujiang, Shao Jianda. Transient optical properties in fused silica measured by time-resolved high power laser photometer[J]. Chinese Optics Letters, 2019, 17(5): .