Effect of mismatched spacing for 4f configure on output pulses of Dammann-type fitters

The misalignment of 4f-configure femtosecond pulse shaping system with space-time conversion can cause aberrations of the output pulse. With theoretical analysis, the effect of the mismatched spacing between the components of 4f Fourier processing system for equally-spaced and unequally-spaced Dammann filters is calculated in this paper. It is concluded that the uniformity and the intensity of the output pulse are relevant to the spacing misalignment. As the intensity of center pulse lowers, the output pulses have more side wings. For the laser facility with 12 cm focus length, when the mismatch is less than 1 cm, the output pulse will not be affected seriously.