Results of experimental and theoretical work performed to compare diffraction patterns and focal distributions of a Fresnel zone plate illuminated by ultrashort
pulsed and cw laser beams are presented. It is shown that the foci intensities of
pulses are considerably lower than those of cw beams while the focal widths in the axial and radial directions are broadened. Calculations also indicate the spectral modulation along the center of the diffraction patterns. These phenomena are explained by the coherent superposition of the composing frequency content.
© 2006 Optical Society of America
Equations on this page are rendered with MathJax. Learn more.