Optical Tweezers And Spanners

No comic-book science-fiction story would be complete without a laser gadget of some description. Often featuring as deadly weapons, lasers also appear as strange medical tools or as devices to trap and deflect alien spacecraft. Physicists will naturally be highly sceptical about the possibility of using lasers to trap macroscopic objects, but a quick glance at the latest research reveals a different picture. Lasers are now widely used in biotechnology laboratories to manipulate living cells, parasites and even single strands of DNA – and a nothing has to actually touch the samples.