Quasi focused characteristics of laser beam with waviness modulation

Based on the diffraction integral theory, the quasi-focused characteristics of a laser beam with waviness modulation have been studied theoretically and numerically in the paper. The effect of waviness modulation and defocused distances on the energy-concentration-rate and intensity distribution as well as pattern of defocused spot have been analyzed in detail. The computing results show that to control the defocused distance or to decrease the size of waviness modulation in the median frequency will improve the energy-concentration of focal spot.