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New Headphones Generate Sound With Carbon Nanotubes
MTorrice writes "A new type of headphone heats up carbon nanotubes to crank out tunes. The tiny speaker doesn't rely on moving parts and instead produces sound through the thermoacoustic effect. When an alternating current passes through the nanotubes, the material heats and cools the air around it; as the air warms, it expands, and as it cools, it contracts. This expansion and contraction creates sound waves. The new nanotube speaker could be manufactured at low cost in the same facilities used to make computer chips, the researchers say."
And it exists in the real world: "The Tsinghua researchers integrated these thermoacoustic chips into a pair of earbud headphones and connected them to a computer to play music from videos and sound files. They’ve used the headphones to play music for about a year without significant signs of wear, Yang says. According to him, this is the first thermoacoustic device to be integrated with commercial electronics and used to play music."
Could be nice way of sidestepping the Chinese and their "rare earth" near-monopoly.
Judging from the author's names and affiliation, I quite doubt that it was their main motivation... :)
Yang Wei *, Xiaoyang Lin , Kaili Jiang *, Peng Liu , Qunqing Li , and Shoushan Fan
Department of Physics and Tsinghua-Foxconn Nanotechnology Research Center, Tsinghua University, Beijing 100084, P. R. China
But, it's still VERY COOL!
Paul B.
The Tsinghua researchers...
My first thought upon reading the summary was, "Which Tsinghua University"? In this case it's the one in Mainland China, but there's a fascinating backstory behind my initial confusion regarding the history of Tsinghua University.
Following the defeat of the Boxer Rebellion (1899 - 1901), the China was made to pay an enormous sum in reparations to the great powers -- Russia, Germany, France, Britain, Japan, and the US. While the American share of the reparations was relatively minor (about 7% of the total) it still represented an excessive amount. American Secretary of State John Hay -- serving in the administration of Teddy Roosevelt -- arranged for about a third of the funds to be used for to set up scholarships, as well as a new school in Beijing which served to prepare students for overseas study in the US. It was this institution that eventually became Tsinghua University, one of the most prestigious learning institutions in China.
There's more to the history however. Following the Chinese Civil War, the defeated Nationalists retreated to Taiwan. A large portion of the Tsinghua staff fled with them and founded a new Tsinghua University in Taiwan (or perhaps they merely re-located the original to Taiwan, depending on your point of view). This other Tsinghua went on to become one of the top Universities in Taiwan as well.
Sadly they actually require more power not less. So you are left with durability advantage, "sounds" like they would have a very small niche market if they ever make them commercially available.