Laser device, and extreme ultraviolet light generation system

An extreme ultraviolet light source system for generating extreme ultraviolet light by irradiating a target substance with laser light to make the target substance into plasma, the system comprising:

• at least one amplification unit configured to amplify laser light emitted from a laser oscillator;
• an amplification control unit configured to control the amplification unit;
• and
• an extreme ultraviolet light generation chamber on which laser light emitted from the amplification unit is made incident and in which extreme ultraviolet light is generated with use of the laser light,
• the amplification unit including:
• an incident-side optical adjustment unit on which laser light is made incident, the incident-side optical adjustment unit including a wavefront adjustment unit configured to adjust a wavefront of the laser light, and a first direction adjustment unit configured to adjust an optical axis of the laser light;
• an amplifier disposed downstream the incident-side optical adjustment unit in a transmission direction of the laser light, the amplifier being configured to amplify the laser light emitted from the incident-side optical adjustment unit;
• an emission-side optical adjustment unit disposed downstream the amplifier in the transmission direction of the laser light, the emission-side optical adjustment unit including a second direction adjustment unit configured to adjust an optical axis of laser light emitted from the amplifier;
• and
• a measurement unit disposed downstream the emission-side optical adjustment unit in the transmission direction of the laser light, the measurement unit being configured to measure laser light emitted from the emission-side optical adjustment unit and acquire information on at least one of an optical axis, a wavefront and energy of the laser light,
• the amplification control unit controlling at least one of the incident-side optical adjustment unit and the emission-side optical adjustment unit, based on a measurement result of the measurement unit.