The laser induced damage of multiplayer optical films

As an important part of almost all laser systems, optical film is so fragile that easy to damage because of temperature rise. Based on temperature field theory and thermal conduction equation, the physical model of temperature field of multiplayer films illuminated by Gaussian laser is built. By solving the Maxwell equation, the average energy flow rate of plane wave with unit intensity propagation through the films is obtained. The numerical calculation program of the temperature field of multiplayer films illuminated by 1064nm laser is built using alternating direction-implicit technique. The simulation results show that laser spot radius, heat exchange coefficient, laser power and film material have a great effect on the temperature field of multiplayer films. These are the key factors to damage the optical films. The results obtained in this paper would be both theoretical basis and reference for optical thin film components developing.