Abstract:
A mirror unit may include a mirror, a first holding member holding the mirror, a second holding member holding the first holding member to allow the first holding member to pivot on a first pivot shaft, an actuator provided on the second holding member and configured to allow the first holding member to pivot, and a counter weight provided on the first holding member to allow a centroid of a structure to be substantially coincident with a center of a reflection surface of the mirror. The structure includes the mirror and is pivotable on the first pivot shaft.
Abstract:
A laser apparatus may include a master oscillator, an optical unit provided in a beam path of a laser beam from the master oscillator, a beam adjusting unit provided upstream from the optical unit in a beam path of the laser beam and configured for adjusting at least one of a beam path and a wavefront of the laser beam, a first detection unit provided between the beam adjusting unit and the optical unit in a beam path of the laser beam and configured for detecting the laser beam, a second detection unit provided downstream from the optical unit in a beam path of the laser beam and configured for detecting the laser beam, and a controller configured for controlling the beam adjusting unit based on outputs from the first and second detection units.