Laser device, and exposure device and inspection device provided with laser device

A laser device comprising:

• a laser light output unit that outputs a fundamental wave laser light;
• a wavelength conversion unit that includes a wavelength conversion optical element, and that performs wavelength conversion of the fundamental wave laser light output from the laser light output unit and outputs a converted laser light;
• an output detector that detects a power of the converted laser light output from the wavelength conversion unit;
• a power feedback circuit that controls the power of the fundamental wave laser light output from the laser light output unit according to the power of the converted laser light detected by the output detector such that the power of the converted laser light output from the wavelength conversion unit is maintained in constant;
• a phase matching adjustment configuration configured to adjust a quantity of state that relates to phase matching at the wavelength conversion optical element so as to satisfy a phase matching condition of the wavelength conversion optical element;
• and
• a phase matching control circuit that controls setting of the quantity of state by the phase matching adjustment configuration, wherein
• in a state in which the power of the converted laser light is controlled to be maintained in constant by the power feedback circuit, the phase matching control circuit instructs the phase matching adjustment configuration to adjust the quantity of state in a predetermined range such that the power of the fundamental wave laser light output from the laser light output unit is minimized.