Product Code: JLA_17_4_270

Authors:
Nageswara Rao Tadepalli
Dennis Alexander
David Doerr
Jianchao Li
Haifeng Zhang
Department of Electrical Engineering and Center for Electro-Optics, University of Nebraska-Lincoln, Nebraska 68588-0511

Femtosecond laser pulses are stretched when they pass through an optical microscope objective used for laser machining. The question that must be answered is how much does the pulse stretch passing through the objective. Stretching of pulses would be more prominent in the case of ultrashort laser pulses (∼9 fs). In this article, a study was performed to measure the final pulse duration for a 9 fs laser pulse passing through a microscope objective (Edmund Achromatic Objective Micro 60× DIN, 0.85 numerical aperture). Results indicate that a 9 fs pulse is stretched to 62 fs (i.e., a factor of 6) after passing through the microscope objective.