Laser beam branching apparatus

摘要

A branching mirror and a transfer mirror receiving a laser beam reflected on the branching mirror and outputting a laser beam in a direction parallel to the laser beam coming into the branching mirror are fixed to and mounted on one mirror holder. The mirror holder is movably provided between a branching position at which the branching mirror is located in a light path of the laser beam and an escaping position at which the branching mirror is located outside the light path of the laser beam, and while the mirror holder is located at the beam branching position, a laser beam from a laser oscillator can be introduced to the branching mirror.