| 摘要 |
PURPOSE:To enable the quick removal of dust from a lower window and thereby to reduce the need for window servicing by a method wherein a suction pipe inlet is provided near the lower window inner wall and the suction pipe is connected to a suction pump with the intermediary of a filter. CONSTITUTION:Of windows 2 and 3 provided at both ends of an optical axis in a vertical excimer laser head 1, the lower window 3 is provided in the vicin ity of its inner wall with the inlet of a suction pipe 4, which is connected to a suction pump 6 with the intermediary of a filter 5. The suction pump 6 in actuation causes dust inside the lower window 3 to be collected in a filter 5, and thus-cleaned gas is allowed to return to the laser head 1. In this way, the removal of dust especially from inside the lower window 3 may be accom plished very quickly, which ensures a prolonged, stable laser output. Less work will be required for the servicing of the windows 2 and 3. |
