Damage Properties Of Several Kinds Of Optical Window Materials Under Irradiation Of Femtosecond Laser Pulse

With the development of optical technology, especially the emergence of femtosecond laser, the problem of laser pulse damage to optical materials caused more attention.So it has studied on the damage properties of several kinds of optical window materials (silicon, K8optical glass and silicon glass) under irradiation of femtosecond laser pulse. At first, we introduced the mechanism of femtosecond laser-induced damage of optical materials, and then analyze and summarize the threshold determination and measurement methods of material damage. Finally, we used femtosecond laser pulses to the experimental study of the three optical window material damage characteristics.The specific research has three parts:1. we used visible light scattering method and a plasma flash method determination means, combining the measuring method of R-on-1method to get three kinds of the damage threshold of the material of the window, and the distribution curve of damage threshold was given.2. After the further experimental study on the silicon and K8optical glass we found:damage of silicon showed significant pulse cumulative effect, the K8optical glass of the pulse the cumulative effect is weak, and then explained the different mechanism of injury between silicon and K8glass with microscopic photograph.3. Based on the principle of the caliber effect, we studied the affect of caliber effect to damage threshold by using R:1method. The experimental results showed that as the test spot size increases, the measured material damage threshold decreases, three materials in the femtosecond laser damage threshold changes are in line with the caliber effect theory.