The extreme ultraviolet light source device and method for controlling an extreme ultraviolet light source device

[Problem] An extreme ultraviolet light source device according to the present invention corrects an optical performance of a laser beam in a suitable manner. [Means for Solution] A guide laser beam having an optical axis and a beam diameter substantially equivalent to those of a pulsed laser beam driver, is inserted in a reinforcement system 30, which amplifies a laser beam outputted from a laser oscillator driver 20th The guiding laser beam output from a laser device 50 as a continuous light and introduced into a light path of a pulsed laser beam driver over a guide laser beam introduction mirror 52nd A sensor 44 detects an angle (a direction) of a laser beam and a change of a curvature of a wave front. A wavefront correction controller 60 outputs a signal to a wave front correction unit 34 on the basis of a measurement result of a sensor 36th The wavefront correction unit 34 corrects accordance with a command from the wave front correction controller 60, a wave front of a laser beam so that it becomes a predetermined wavefront.