The electret electrode, the communication device which loads the actuator, the vibrating generator, and the vibrating generating set, and the vibrating generating set which use that

摘要

The electret electrode where surface density of charge improves is offered. Electric conduction film 111 is formed on substrate 102, on electric conduction film 111 1st insulating film after laminating 112 and the 2nd insulating film alternately, the underside, the surface and the electret film 110a where the edge strip is covered - d are laid out with 3rd insulating film 114 and 4th insulating film 115, electret electrode 100 is formed. When containment the same electric charge electret film due to the fact that 1st insulating film 112 and 2nd insulating film 113 exists with 110a - d and electric conduction film 111, magnetic field strength in the film becomes small, when it is the same magnetic field strength, surface density of charge (surface potential) it is possible to make high.