An encoder (10) for a nanopostioner (24) includes a strip of magnetic bits (18) for producing discrete magnetic fields and a giant magnetoresistor (GMR) (14) which changes in electrical resistance in response to changes in the magnetic fields. The GMR (14) is connected to a mass (12) which moves along a path proximate to the strip of magnetic bits (18). A voltage sensor (20) is connected to the GMR (14) to produce digital signals based on the changes in electrical resistance of the GMR (14). A processor (22) calculates the position of the nanopositioner (24) based on the digital signals.
Fries, David P., "Giant magnetoresistance based nanopositioner encoder" (2005). USF Patents. 715.
University of South Florida