Electret capacitive pressure sensor unit array for wrist back gesture recognition

The invention discloses an electret capacitive pressure sensor unit array for wrist back gesture recognition. The electret capacitive pressure sensor unit array is a rhombus array formed by arrangingeight electret capacitive pressure sensor units in a 4*2 arrangement mode. Each electret capacitive pressure sensor unit comprises: an electret film used for sensing pressure change so as to generatedeformation; a back electrode which is opposite to the electret thin film in position, wherein an extremely small air gap is reserved between the back electrode and the electret thin film to serve asan insulating medium, and two electrodes are led out from the metal layer and the back electrode; a printed board which is integrated with a signal preprocessing circuit of the sensor; a cylindrical copper ring, wherein the upper layer and the lower layer of the cylindrical copper ring are respectively covered by an electret film and a back electrode; a signal preprocessing circuit which is integrated on the printed board;