Abstract: The invention concerns a piezoelectric transducer including: a conductive layer between first and second piezo-electric layers; first and third electrodes arranged on the front surface of the second piezoelectric layer; second and fourth electrodes arranged on the rear surface of the first piezoelectric layer; and a control circuit configured to: in a first operating phase, simultaneously apply a non-zero voltage to the first electrode, a non-zero voltage to the fourth electrode, and substantially zero voltages to the second and third electrodes; and in a second operating phase, simultaneously apply a non-zero voltage to the second electrode, a non-zero voltage to the third electrode, and substantially zero voltages to the first and fourth electrodes.

Abstract: The invention concerns a piezoelectric transducer including: a conductive layer between first and second piezo-electric layers; first and third electrodes arranged on the front surface of the second piezoelectric layer; second and fourth electrodes arranged on the rear surface of the first piezoelectric layer; and a control circuit configured to: in a first operating phase, simultaneously apply a non-zero voltage to the first electrode, a non-zero voltage to the fourth electrode, and substantially zero voltages to the second and third electrodes; and in a second operating phase, simultaneously apply a non-zero voltage to the second electrode, a non-zero voltage to the third electrode, and substantially zero voltages to the first and fourth electrodes.

Abstract: Membrane device comprising a support, a membrane suspended on the support, a first actuator in contact with the membrane designed to apply a force on the membrane, a second actuator in contact with the membrane designed to apply a force on the membrane, means of determining the position of the membrane relative to the support and control means of the first and second actuators, said control means applying a deformation signal to one of the first and second actuators to deform the membrane and applying a control signal to the other of the first and second actuators to control displacement of the membrane, application of the control signal being determined by the membrane position.

Abstract: A digital acoustic device including: at least one suspended diaphragm facing a support and at least one actuator associated with the diaphragm, the associated actuator being configured to move the diaphragm away from and/or closer to the support; a stop mechanism configured to interrupt movement of the diaphragm further to activating the actuator when the diaphragm has a non-zero speed, the stop mechanism being sized to interrupt the movement of the diaphragm when the movement of the diaphragm is greater than or equal to 50% of the theoretical maximum stroke of the diaphragm and lower than or equal to 95% of the theoretical maximum stroke of the diaphragm.

Abstract: A digital acoustic device including: at least one suspended diaphragm facing a support and at least one actuator associated with the diaphragm, the associated actuator being configured to move the diaphragm away from and/or closer to the support; a stop mechanism configured to interrupt movement of the diaphragm further to activating the actuator when the diaphragm has a non-zero speed, the stop mechanism being sized to interrupt the movement of the diaphragm when the movement of the diaphragm is greater than or equal to 50% of the theoretical maximum stroke of the diaphragm and lower than or equal to 95% of the theoretical maximum stroke of the diaphragm.

Abstract: Digital loudspeaker comprising a support, a plurality of first membranes suspended on the support, said first membranes being bistable, and said loudspeaker comprising actuator for each of the first membranes that can change each of the first membranes from a first stable state to a second stable state and vice versa, and a controller for controlling said first actuator.

Abstract: Membrane device comprising a support (4), a membrane suspended on the support (4), a first actuator (6) in contact with the membrane designed to apply a force on the membrane, a second actuator (10) in contact with the membrane designed to apply a force on the membrane, means of determining the position of the membrane relative to the support and control means of the first (6) and second (10) actuators, said control means applying a deformation signal to one of the first (6) and second (10) actuators to deform the membrane and applying a control signal to the other of the first (6) and second (10) actuators to control displacement of the membrane, application of the control signal being determined by the membrane position.