“Nanotubes assemblies of various types are black and highly conductive,” said Dr. Mikhail Kozlov, a research scientist and the study’s lead author. “Their dark, conductive surface can be effectively heated with laser light or electricity to induce variations in the pressure of the air around the nanotubes — which we perceive as sound. It’s called the photo- or thermo-acoustic effect, and it’s the same principle Alexander Graham Bell used to produce sound on the first telephone.”
With laser excitation, no electrical contact with the nanotube speaker is required, making the speakers wireless.
“Speakers made with carbon nanotube sheets are extremely thin, light and almost transparent,” Kozlov said. “They have no moving parts and can be attached to any surface, which makes the surface acoustically active. They can be concealed in television and computer screens, apartment walls, or in the windows of buildings and cars. The almost invisible strands form films that can ‘talk.’”
In addition to filling a room with sound from invisible speakers, nanotube speakers could easily cancel sound from the noisiest neighbor or dim the roar of traffic rushing past a neighborhood, using the same principles as current sound-canceling technologies.
“The sound generation by nanotube sheets can help to achieve this effect on very large scales,” Kozlov said.
Jack Logan on 25 Mar 10Listen to David Hyman and you're likely to make money--or at least improve the audio on your headphones. Among investors in Hyman's new digital music service, Mog, are Scott Jones, the inventor of voice mail, and Stephen Simon, who heads the equity arm of the largest publicly traded real estate company in the U.S. "David is a visionary," says Simon. "He has insight into this business no one else has." The musician and producer Quincy Jones is a Hyman admirer; so is Jimmy Iovine, the chairman of Interscope Records. Iovine recently asked Hyman to weigh in on a pair of high-end headphones he was designing called "Beats by Dr. Dre." Hyman tested their fidelity and made suggestions on the color scheme, with which Iovine agreed.
