Patent ID: 7471031

Claim:
A piezoelectric MEMS element, comprising: a substrate having a first surface; a movable head having a second surface faced to the first surface; first and second movable electrodes arranged on the second surface; first and second pairs of stationary electrodes formed on the first surface, the first pair of stationary electrodes being arranged to face the first movable electrode with a gap and the second pair of stationary electrodes being arranged to face the second movable electrode with the gap; and a driving beam structure configured to drive the movable head, the driving beam structure including a piezoelectric film generating a driving force, which is elongated from the movable head to the end of the driving beam structure in a longitudinal direction of the driving beam structure, the end of the driving beam structure being fixed to the substrate to support the movable head, first and second variable capacitors being formed between the first movable electrode and the first pair of stationary electrodes and between the second movable electrode and the second pair of stationary electrodes, and having first capacitance and second capacitance, respectively, the first capacitance and second capacitance being varied depending on the driving of the movable head.