Adaptive optimization for nonlinear optical frequency conversion of femtosecond laser

The adaptive optical system with close-loop control can modulate the wavefront of femtosecond pulses, which can effectively improve the reduced efficiency caused by the phase distortion and optical deviation in the interaction between laser and materials. Using a programmable pure-phase liquid crystal spatial light modulator, the adaptive optimal system based on simulated annealing algorithm can automatically compensate the efficiency decline caused by the phase distortion and optical deviation during the second harmonic generation process of femtosecond pulses in a BBO crystal.