Abstract: A piezoelectric device comprises at least one element comprising at least one sheet of piezoelectric material. The element is mounted on a circuit board comprising at least one conductive layer having at least one opening. The element is located on the opening and supported by edges of the opening in such a manner that the opening extends laterally beyond the area of the sheet of piezoelectric material. The element is sandwiched between an overlay and the circuit board in such a manner that vibrations of the sheet of piezoelectric material are sufficient to cause vibration of the overlay.

Abstract: A device for detecting the likelihood of the presence of at least one human finger on a surface, and a method of using the device in the user interface of a machine, device or system. The device comprises at least one element having piezoelectric characteristics, located under a surface, the element arranged in the device in such a manner that a force when exerted on the surface, such as when the surface is pressed by finger, is transferred to mechanical stress of the element, the element then producing a voltage output in response to the mechanical stress. Also included are means for measuring the voltage output in a predefined time period and means for determining the degree of stability of the measured voltage output, and configured to indicate whether or not the degree of stability shows that the measured voltage output is likely to be a human finger or not.

Abstract: An apparatus for reducing energy consumption in monitoring means of a plurality of piezoelectric components comprises a plurality of piezoelectric components as well as monitoring means for monitoring the status of the piezoelectric components. The monitoring means have two states namely active and inactive. The piezoelectric components are connected in parallel to each other. A current detecting circuit comprises a switch and a resistor that is connected in parallel to the switch. A controller having two states that are active and inactive. The controller is configured to open the switch in response to the controller being in the inactive state and to close the switch in response to the controller being in the active state. The closing of the switch triggers a state change in the monitoring means from their inactive state to their active state.

Abstract: A device for detecting the likelihood of the presence of at least one human finger on a surface, and a method of using the device in the user interface of a machine, device or system. The device comprises at least one element having piezoelectric characteristics, located under a surface, the element arranged in the device in such a manner that a force when exerted on the surface, such as when the surface is pressed by finger, is transferred to mechanical stress of the element, the element then producing a voltage output in response to the mechanical stress. Also included are means for measuring the voltage output in a predefined time period and means for determining the degree of stability of the measured voltage output, and configured to indicate whether or not the degree of stability shows that the measured voltage output is likely to be a human finger or not.

Abstract: An apparatus for reducing energy consumption in monitoring means of a plurality of piezoelectric components comprises a plurality of piezoelectric components as well as monitoring means for monitoring the status of the piezoelectric components. The monitoring means have two states namely active and inactive. The piezoelectric components are connected in parallel to each other. A current detecting circuit comprises a switch and a resistor that is connected in parallel to the switch. A controller having two states that are active and inactive. The controller is configured to open the switch in response to the controller being in the inactive state and to close the switch in response to the controller being in the active state. The closing of the switch triggers a state change in the monitoring means from their inactive state to their active state.