Tiniest microphone developed to listen to microscopic sounds

BBC News reported today in its article, “Tiny Ear Listens to Hidden Worlds“, that scientists from the UK have developed a microphone based on the techniques used in optical tweezers – suspending very small glass or plastic beads in laser light and measuring their movement.

“We are now using the sensitivity afforded by the optical tweezer as a very sensitive microphone,” said Professor Jon Cooper from the University of Glasgow, who is heading the micro-ear project.

“The optical tweezer can measure or manipulate at piconewton forces,” said Professor Cooper. A piconewton is a millionth of the force that a grain of salt exerts when resting on a tabletop.

The site includes sound samples and a visual representation of the capturing of the sound of bacterial flagella movement.