<title>New approach to the problem of ultrashort-pulse diffraction and focusing</title>

Abstract

The scalar problem for a plane wave pulse spreading behind the diaphragm is solved. The calculation is carried out on the base ofthe non-stationary Kirchhoff-Sommerfeld integral and the expansion ofpulse in terms ofwavelet. The round and square diaphragm are considered. The pulse propagation under the condition offocusing is calculated The Greenfunction of the problemfor the round diaphragm with and without nonabberativefocusing is constructed