Solid-state laser system and excimer laser apparatus

An excimer laser apparatus comprising:

• a solid-state laser system including
• a first semiconductor laser device configured to output a first pulse laser beam having a first wavelength, and
• a first burst pulse light generating apparatus including a first generation stage that generates a first burst pulse light beam including two pulse laser beams by branching the first pulse laser beam into a first branch light beam and a second branch light beam, and then coupling the first branch light beam and the second branch light beam,
• the first generation stage including
• a first optical path having a first optical path length for propagating the first branch light beam, and
• a second optical path having a second optical path length, which is longer than the first optical path length, for propagating the second branch light beam;
• a wavelength conversion system configured to generate and output a seed light beam based on the first burst pulse light beam;
• and
• an amplifier configured to amplify the seed light.

A solid-state laser system comprising:

• a semiconductor laser device configured to output a pulse laser beam;
• and
• a burst pulse light generating apparatus including one or more generation stages that generate a burst pulse light beam by branching the pulse laser beam into two and then coupling the branch light beams,
• the burst pulse light generating apparatus including, when n is an integer equal to or larger than one, n pieces of the generation stages connected in series, and generating the burst pulse light beam including 2n pieces of pulse laser beams.