US Patents 8208661 and 8208675 - Headphones and loadspeaker with CNT thermoacoustic material

http://www.freepatentsonline.com/8208661.html
http://www.freepatentsonline.com/8208675.html

In the last few years Foxconn has been obtaining several basic patents for applications of carbon nanotubes as acoustic transducers. These latest patents focus on headphones and loudspeakers incorporating these carbon nanotube transducers.

Claim 1 of US 8208661:

1. An apparatus comprising:

a headphone, the headphone comprising:

at least one housing; and

at least one sound wave generator disposed in the at least one housing, the at least one sound wave generator comprising at least one carbon nanotube structure, the at least one carbon nanotube structure is capable of producing sound by a thermoacoustic effect;

wherein the at least one carbon nanotube structure is capable of producing sound in response to an electrical signal, the electrical signal is capable of causing the at least one carbon nanotube structure to increase in temperature;

the carbon nanotube structure is in contact with a medium and is capable of transmitting heat to the medium.

Claim 1 of US 8208675:

1. A loudspeaker, the loudspeaker comprising:

an enclosure; and

at least one sound wave generator disposed in the enclosure,

wherein the at least one sound wave generator comprising at least one carbon nanotube structure, the carbon nanotube structure is capable of converting electrical signals into heat and transferring the heat to a medium in contact with the at least one carbon nanotube structure to cause a thermoacoustic effect.