US Patent 7286210 - Carbon nanotube optical sensor with wavelength tuning

http://www.freepatentsonline.com/7286210.html

This patent discloses an interesting method of tuning carbon nanotube optical sensors to particular wavelengths by using mechanical pressure or electrical charge. Claim 1 reads:

1. A method for causing a semiconducting carbon nanotube material to act as a passive sensor of a physical quantity, the method comprising: (a) controlling the semiconducting carbon nanotube material in accordance with the physical quantity to cause a change to an optical absorption or reflection characteristic of the semiconducting carbon nanotube material which depends on light wavelength but not on light amplitude; (b) applying light to the semiconducting carbon nanotube material; (c) receiving the light which has been applied to the semiconducting carbon nanotube material; (d) determining the change to the optical absorption or reflection characteristic from the light receive in step (c); and (e) determining the physical quantity from the change determined in step (d).