David Armstrong

David Armstrong is a Product Manager at Coherent (Santa Clara, CA).

(Courtesy of Queen's University, Belfast, United Kingdom)
FIGURE 1. Traditional pulse compressors based on gratings are relatively large, particularly when designed for high-energy amplified pulses. Here a custom compressor is used with an ultrafast system that produces pulse energies up to 20 joules.
Test & Measurement

FEMTOSECOND PULSE MANIPULATION: New tools compress and shape ultrafast pulses

Jan. 7, 2009
Researchers can manipulate femtosecond laser pulses as never before, benefiting applications from biological imaging to terahertz spectroscopy and quantum reaction control.
(Image courtesy of Ricardo Mostany and Carlos Portera-Cailliau, Dept. of Neurology, University of California Los Angeles)
FIGURE 1. This z-axis image was reconstructed from a stack of 160 separate xy image slices, 5 µm apart. It was recorded in vivo from an anesthetized mouse through a glass cranial window using 910 nm two-photon excitation and shows two layer 5 cortical neurons transgenically labeled with GFP. The benefits of high power and optimized pulsewidth can be seen in the z-axis image slice of a cortical neuron of the mouse brain, which has a total depth of 800 µm.

Ultrafast lasers advance deep-tissue imaging

March 1, 2008
Recent developments in Ti:sapphire lasers are extending CARS and multiphoton microscopy, and enabling new nonlinear imaging methods.