Ultra sound transmitter and receiver for motor vehicle distance warning system

摘要

The ultra sound transmitter and receiver is a capacitive or electrostatic ultra sound transducer. Preferably, the transducer includes a first electrode which is formed by a light membrane and a second electrode formed by a solid counter body. The membrane and the solid body have an electrically conducting layer. The membrane has a metallised plastic foil. A gas pad is provided between the membrane and the coating of the solid body. The coating of the solid body has etched recesses which increase the yielding.