A STUDY OF RANDOM PHASED LASER SPOTS

Far-field images produced using different random phase plates on a pul sed laser beam focused with various f/numbers were recorded by a charg e-coupled device (CCD) camera and then analyzed. Envelope spot sizes a gree with diffraction theory while mean sizes of the pattern structure s have been found to be larger than the diffraction limit. The probabi lity density distribution of intensity in the focal plane is not the e xpected exponential. A central symmetry of the pattern has also been s een after suitably aperturing the beam, Some consequences for the use of powerful RPP-treated laser beams in laser-plasma interactions are d iscussed.