It takes a big screen to see — and move — some really, really small things.
University researchers in Glasgow, Scotland, and Bristol, England, are now using an iPad to move and manipulate microscopic particles. A custom app dubbed (not surprisingly) "iTweezers" interfaces with holographic optical tweezers — in non-college dummy talk, using laser beam light to move these particles under a microscope. Think of the mechanical manipulator arms (or "waldos") used in atomic labs, only with no physical components.
The researchers view the microscope's output on the iPad, then use finger gestures to move (swipe), raise/lower (pinch/pull), and rotate (two-finger swipe) the target object – including a tiny rod 300 nanometers wide. (That's three hundred billionths of a meter — the conversion to inches will be left as a mental exercise for the reader.) Another advantage to the iPad/iTweezer combo is that it can control the optical tweezers wirelessly and/or far from the site — a big plus for the more dangerous/toxis molecules out there.
A complete downloadable paper on the technique can be found at the Journal of Optics website.
(When David Morse murmured "Small moves, Ellie, small moves…" to Jodie Foster in CONTACT, he probably wasn't thinking THIS small.ÔªøÔªø)