Resources Contact Us Home
Touch pad

Image Number 11 for United States Patent #7411581.

A touch pad (101) includes transducers (201-204) for receiving acoustic signals resulting from touch events, such as the continuous movement of a fingertip across the surface (105) of the touch pad. The acoustic signals are acquired at different transducer locations in the surface. Signals from different transducers are combined, preferably in antiphase, to improve signal characteristics. The transducer signals are supplied to a stereo analogue to digital converter (407). Phase differences (706) are obtained and compared (703) with phase difference profiles (607) of known location, in order to identify the location of the touch event. An index (606) is used to identify candidate locations to reduce the amount of processing. Interpolation (705) is used to locate the touch event between profile locations.

  Recently Added Patents
Evaluating programmer efficiency in maintaining software systems
Facial recognition using a sphericity metric
Method for incubating the contents of a receptacle
Social network user data advertising
Verbena plant named `Duempsopicha`
Aware manufacturing of integrated circuits
Austenitic stainless steel welding wire and welding structure
  Randomly Featured Patents
Transmitter and receiver units for spatial position measurement system
Soft drink bottle holder
Method for providing service in IP-based network system
Haworthia plant named `L1`
System and method for testing one or more dies on a semiconductor wafer
Flavored cigarette
Insect trap apparatus
Expandable controllers capable of connecting in series to a control deck of a video game machine
Golfing aid
Rack assembly