Close

Search

Search Menu
Photonics Media Photonics Buyers' Guide Photonics EDU Photonics Spectra BioPhotonics EuroPhotonics Industrial Photonics Photonics Showcase Photonics ProdSpec Photonics Handbook
More News
SPECIAL ANNOUNCEMENT
2016 Photonics Buyers' Guide Clearance! – Use Coupon Code FC16 to save 60%!
share
Email Facebook Twitter Google+ LinkedIn Comments

Fast Flash, Gating Image Through Turbid Media

Photonics Spectra
Feb 2005
Experiments by a team at the City College of the City University of New York indicate that the direct optical imaging of objects through scattering media may be improved with the use of ultrashort illumination and time gating. The findings may have an impact on lidar-based remote sensing and underwater surveillance, and on biological imaging.

As described in the Jan. 3 issue of Applied Physics Letters, the work involved variants of laser range gating, which commonly employs nanosecond-long pulses of 532-nm light from a Q-switched Nd:YAG laser and gating times of a similar duration.

The scientists instead used a Ti:sapphire oscillator and amplifier system to produce 130-fs and 3.5-ns pulses of 800-nm radiation, and they set the time gate of their intensified camera system for 80 or 500 ps. Images of a 1.41-lp/mm resolution target thus were collected through a suspension of 500-nm TiO2 particles in water in four combinations of illumination and gate durations.

The highest resolution image was obtained with 130-fs illumination and an 80-ps gate width, centered on the time of the returning ballistic signal.


Comments
Terms & Conditions Privacy Policy About Us Contact Us
back to top

Facebook Twitter Instagram LinkedIn YouTube RSS
©2016 Photonics Media
x Subscribe to Photonics Spectra magazine - FREE!