Scientists study orca ears, employ lasers to create hyper-sensitive underwater microphone

By Brian Heater  posted Jun 27th 2011 5:13AM

There are plenty of reasons to want to monitor what's going on in the ocean, from whale migration, to the recent stylistic resurgence of hot crustacean bands. There are certain inherent difficulties, however, in creating a powerful underwater microphone, namely all of that water you've got to contend with. A team of scientists has taken cues from the design of orca ears, in order to develop a powerful microphone that can work far beneath the waves. The researchers developed membranes 25 times thinner than plastic wrap, which fluctuate as sound is made. In order to operate at extreme depths, however, the microphone must fill with water to maintain a consistent pressure. So, how does one monitor the minute movements of a membrane hampered by the presence of water? Lasers, of course! The hydrophone can capture a 160-decibel range of sounds and operate at depths of 11,000 meters, where the pressure is around 1,100 times what we're used to on earth. So if the orcas themselves ever master the laser, at least we'll be able to hear them coming.