Simulation of multibeam imaging in three-dimensional space and time with a diffractive optical element illuminated with a femtosecond pulse

A simulation of arbitrary beam array generation by ultrashort pulses using diffractive optical elements (DOEs) will help us to understand and optimize various pulse propagation effects in the target plane prior to the design and fabrication of optical systems for a variety of applications. The spatial-temporal distortion of a few femtosecond optical pulses in the imaging plane on propagation through a DOE is numerically studied with an efficient algorithm. A visualization of the pulse evolution is presented in three-dimensional space and time. The propagation effects include pulse front delay, lateral walk-off of the various spectral components in the imaging plane and the time dependence of the diffraction pattern in the target plane.