Search Menu
Photonics Media Photonics Buyers' Guide Photonics EDU Photonics Spectra BioPhotonics EuroPhotonics Industrial Photonics Photonics Showcase Photonics ProdSpec Photonics Handbook
More News
Email Facebook Twitter Google+ LinkedIn Comments

Tweezers May Power Micromachines

Photonics Spectra
Jun 2001
A team at St. Andrews University has demonstrated a variant of optical tweezers that can cause micron-size objects to rotate. The technique could be used to drive miniature cogs and motors in micromachines or to orient DNA strands for polymerase chain reaction amplification.

The researchers, who reported their findings in the May 4 issue of Science, split the laser beam with a holographic element to create an interferometer that generated an intensity pattern at the focus of the tweezers when the legs were recombined. By tilting a glass plate that they inserted in one arm of the interferometer, they could alter the pattern, creating a rotating spiral. Objects inserted into the pattern, including silica microspheres, a glass rod and a Chinese hamster chromosome, rotated at controlled speeds exceeding 5 Hz.

The team used a 300-mW Nd:YVO4 laser in the experiments, which produced 13 mW in the interference pattern at the focus. Rotation rates of up to hundreds of hertz are possible with an optimized setup.

Research & TechnologyTech Pulse

Terms & Conditions Privacy Policy About Us Contact Us
back to top
Facebook Twitter Instagram LinkedIn YouTube RSS
©2019 Photonics Media, 100 West St., Pittsfield, MA, 01201 USA,

Photonics Media, Laurin Publishing
x Subscribe to Photonics Spectra magazine - FREE!
We use cookies to improve user experience and analyze our website traffic as stated in our Privacy Policy. By using this website, you agree to the use of cookies unless you have disabled them.