Michigan Technological University

Department of Physics

is pleased to announce a colloquium

with

Changgong Zhou

(Advisor: Dr. Edward Nadgorny)

Laser beam diffraction by small circular aperture
Laser Guided Direct Write technology takes advantage of the laser field inside a hollow-core fiber or the field diffracted by a small circular aperture in the immediate neighborhood to transmit and deposit small droplets. Recent study shows that the aperture might give better performance. To study the field behind a 25-micron aperture (in the range of 10 - 30 microns), where traditional approximation methods are unable to give any useful result, a modified Helmholtz-Kirchhoff diffraction theorem has been used with the exact solution of the scalar wave equation. Numerical calculation result will be discussed in comparison with the results obtained with other methods.
 
March 28, 2002, Thursday
4:00 p.m., Fisher 139
Refreshments will be available