Laser driver beam combination for fast ignition

Based on the estimated parameters of fast ignition, the requirements for laser-beam power intensity and energy are used to analyze the possibility of realizing fast ignition by coherent combination and noncoherent combination. The practical distorted wavefront is considered to analyze the farfield focal spot. Non-coherent combination needs more beams for energy requirement and to limit angle drifting in ±2 μrad through improving laser driver’s stability. Coherent combination is beneficial for achieving smaller focal spot and higher power intensity, simultaneously reducing the requirement of energy, but single beam wavefront correction can not improve the power intensity in this method, which leads to combined wavefront correction of the total clear aperture with complex monitoring a