Study On The Built-Up High Power Multi-Pass Solid-State Laser Systerm's Power Balance

Successful demonstration of laser fusion feasibility is critically dependent on the ability to drive the implosion with a very high degree of symmetry over the whole time of the target irradiation. Irradiation uniformity over the entire surface of the target can only be achieved with a fairly large number of incident laser beams symmetrically disposed around the target. That is the same output energy, the same output pulse shape and beam synchronization of each beam, hence the term "power balance" . The multi-pass amplification is a fine laser amplifier configuration. It can improve system output capabilities and decrease system costs. However, the built-up structure of the main amplification implies that the gain of the multi-pass amplification cannot be adjusted easily. Therefore, it is necessary to study the optimum strategies for compensating for intrinsic difference among beams and to determine the allocation of random variations to subsystems to meet the energy and balance requirement. The follows are the contents and results in this thesis:1. A multi-beam model has been developed for the purpose of estimating the power imbalance. The multi-beam model has been used to simulate individual laser chain with differing performance parameters. The...