抄録
Arrayed KDP cells with 20cm aperture for third harmonic generation of two beam Glass Laser System GMII has been constructed. The doubler with four segments of KDP crystals and the tripler with four were altogether assembled in one cell. Each crystal has been finished with a diamond turning machine. A crystal orientation and measuring system with an accuracy of 2″″ using repetitive Q-switched YAG laser has been used to measure the phase matching angle and to determine segment-to-segment angle correction. The angular accurracy of each KDP segment for the doubler was set less than 12″″ and for the tripler, 6″″. Propylene carbonate was used for index matching fluid. Maximum energy conversion efficiency of 60% for third harmonic generation was obtained at the input energy of 60J (2.2 GW/cm2, 100ps pulse), and the near field pattern was uniform.
