Analysis of Damage Thresholds of Laser Scanning Mirrors using Ultrashort Laser Pulses

A series of laser induced damage threshold experiments are carried out at various wavelengths and angle of incidences (AOI) with a τP = 10 ps laser. Various fused silica laser scanhead mirrors are tested according to the conditions of its intended use. Damage is initiated by a focused beam so that a safe operating value of fluence can be derived. Results indicate that the threshold is dependent on the AOI which is caused by the limitations of the coating design. An increase in AOI results in a higher percentage of laser energy being coupled rather than reflected.