Optical quality of a combined aerodynamic window

The novel aerodynamic window with a pump cavity and a supersonic gas jet described in /1/ shows considerable improvements in operation performances such as shock-free operation range, reduction of the mass flow rate as well as operation stability. Its optical quality at different operation states has been investigated firstly with the schlieren method. Then the window was combined with a 5 kW CO2 laser using an unstable resonator. The influences of the window on the laser beam quality at different operation states have been investigated. The results will be presented in this paper.