A technique for implementing a center key in a capacitive sense radial slider interface without use of center mechanical button. A user interaction with an array of capacitive sensors within the radial slider interface is sensed. It is determined whether at least a threshold number greater than one of...http://www.google.es/patents/US7253643?utm_source=gb-gplus-sharePatente US7253643 - Uninterrupted radial capacitive sense interface
