FAR-ZONE DIFFRACTION OF POLYCHROMATIC AND NONSTATIONARY PLANE-WAVES FROM A SLIT

The concept of spectral representation of nonstationary wave fields is considered, and as an example the far-zone diffraction from a slit is discussed. In particular it is shown that the red shift of the spectr um of the diffraction pattern for the off-axis points of observation i s the same for stationary polychromatic and nonstationary light source s with the same spectral composition and that under certain conditions a slit splits the Gaussian-shaped pulse into two separate pulses.