Automatic wave-front correction of a femtosecond laser using genetic algorithm

This paper describes the automatic wavefront correction of a femtosecond laser using a genetic algorithm (GA). Because the femtosecond laser system can generate high power levels, over one megawatt, during femtosecond (10^-15 sec) pulses, this system can be used for high-precision machining without abrasions due to heat. However, because the laser beam from a femtosecond laser fluctuates based on some aberrations, it is difficult to focus the beam efficiently with focusing lens or mirrors for machining. It is, therefore, essential to reduce the aberrations. In order to achieve this, we propose an automatic correction method using GA and a deformable mirror (DM) to correct the wave-front of femtosecond lasers. As the experimental results demonstrate, this method can achieve automatic wave-front correction to increase the laser peak power by 21%.