In most applications of piezoelectric devices, electric energy is applied to the devices via lead wires soldered on the electrodes of piezoelectric components. At high input voltage, large vibration amplitudes or high temperature, the lead wires may fall off, causing the breakdown of devices. The soldered wire may limit the miniaturization, affect the properties of micro and nano devices and hinder the applications of piezoelectric devices in rotary mechanisms. The fundamental limitations of direct drive of piezoelectric devices via lead wires soldered on the electrodes necessitate the pursuit of wireless energy transmission to piezoelectric components which is the bottleneck for further widespread applications of microsystems. This book provides a new method of wireless drive of piezoelectric components by focused electric field to miniaturize and widen the application range of piezoelectric devices. A needle electrode is used to focus the electric field. The wireless energy transmission to piezoelectric components depends on the operating frequency, electrical load, electric field, electrode pattern, vibration mode and distance of the piezoelectric components.