4 - New Wireless Sensor Uses Light to Run Nearly Perpetually

[4]
New Wireless Sensor Uses Light to Run Nearly Perpetually
[#] D. Levitan, "New Wireless Sensor Uses Light to Run Nearly Perpetually" IEEE Spectrum, spectrum.ieee.org, February 22, 2010. [Online]. Available: http://spectrum.ieee.org/energywise/biomedical/devices/new-wireless-sensor-uses-light-to-run-nearly-perpetually. [Accessed: March 14, 2010].

Power consumption is always a great concern for engineers when they set out to design a device. How much will it consume, for how long will it last, and how to keep supplying power to a device are all key questions in the design process. Well, a team from the University of Michigan has designed a sensor that utilizes solar power to allow the sensor to function autonomously for many years.

The sensor is only 9 cubic-millimeters, consumes a miniscule 100 picowatts when in 'sleep mode' and only 2.1 microwatts when making sensing measurement. The sensor is outfitted with a thin-film lithium-ion battery (the kind that is typically found in electronics), but it only needs to be exposed to a light source periodically. Professor David Blaauw, professor electrical and computer engineering at U of M says the source of light need not be from the sun and that device can actually function with indoor lighting sources.

A similar system was developed by a team at Cornell University which exploits the ability of a piezoelectric power system to store energy based on tiny vibrations or mechanical movements.

The light-powered sensor could be used to measure pressure in the eyes or brain or inside tumors. Blaauw added that the sensor, even when embedded within the eye of an individual, could still utilize solar power for its operation.