UV beam sources for double pulse generation

Summary form only given. The concept of two laser sources has been developed whose pulse generation signals and light paths are synchronized. This can be realized with an accuracy in the nanosecond range, so the two temporally shifted pulses act onto the material with a separation significantly shorter than the thermal dissipation time of several microseconds, hence appearing to the target as one pulse but keeping the original pulse energies of the two given pulses. The acoustooptically Q-switched lasers consist of a double folded linear cavity, and are pumped from one side by a fiber-coupled diode laser module producing 20 W. The fundamental radiation is frequency doubled and tripled by two LBO crystals.