Optimum Design of Spatial Filter Pinhole in High Power Solid Laser System

Spatial filter is the key unit of high power solid laser system for nonlinear increase control. However, the plasma closure occurred in pinhole is easily happened when long pulse running which may reduce the beam quality. The optimum design of pinhole will meet the needs for long pulse running which is important for spatial filter application. This paper based the key problems, such as suppression of nonlinear growth and plasma closure, discussed the optimum design in three aspects: filter size design, geometry design and the material design. Provide the reasonable principle for pinhole design.