Diagram: Bending Wave

Bending Wave

Sensor Materials

Glass substrate, piezoelectric transducers

Principle of Operation

  • Touch creates a bending wave through the medium of the glass substrate.
  • Bending waves radiate to the sensor edges and are detected by piezoelectric receptors in border area.
  • Electronics compute touch location based on algorithms or by use of signal comparison references.

Advantages

  • Impervious to surface contaminants
  • Touch activated by bare finger, gloved finger, or stylus
  • Transmission is >90%
  • Able to offer flat front surface design (no bezel)

Disadvantages

  • Few major suppliers
  • Limited to 1 resolvable point with gesture capability