Patent ID: 6603787
Filing Date: 2003-08-05
Classification: F16C,H01S

Abstract:
A discharge-pumped excimer laser device comprising:a casing filled with a laser gas; a pair of main discharge electrodes disposed in said casing for producing an electric discharge to discharge-pump the laser gas to emit a laser beam; a cross-flow fan for producing a high-speed laser gas flow between said main discharge electrodes, said cross-flow fan having a rotatable shaft projecting from opposite ends thereof; magnetic bearings, said rotatable shaft being rotatably supported in a non-contact manner by said bearings; protective bearings for supporting said rotatable shaft when said magnetic bearings are not in operation; and a motor for actuating said cross-flow fan; said magnetic bearings including radial magnetic bearings disposed respectively on the opposite ends of said cross-flow fan, said motor being disposed on an end of said rotatable shaft near one of said radial magnetic bearings, said one of the radial magnetic bearings having a bearing rigidity greater than the bearing rigidity of the radial magnetic bearing which is disposed remotely from said motor.