From: http://www.optics.org/articles/news/11/3/18/1

Tweezers offer point and drag control
23 March 2005

Biologists benefit from 4D optical tweezers that move cells in real-time at the touch of a computer mouse.

Scientists in Denmark have developed an optical manipulation system that moves tiny particles in 3D in real-time at the click of a mouse button. The computer-controlled “4D optical tweezers” are the brainchild of Jesper Glückstad and his co-workers from Risø National Laboratory in Roskilde (Applied Physics Letters 86 074103).

3D arrangements

“Up to 80 particles have now been simultaneously manipulated by point and drag of a simple PC mouse interface with less than a Watt of near-infrared laser light,” Glückstad told Optics.org. “In addition, we are now able to view in 3D while manipulating -- this capability is unique since it allows full visualization and therefore precise position and velocity control.”

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