| 摘要 |
PURPOSE:To produce charges having a potential equal to the algebraic sum of the potential of elements themselves with uniform distribution, on the electret member at the upper side, by maminating a pair of electret elements opposed with back electrodes on a grounded conductor. CONSTITUTION:A pair of electret elements 231, 232 coated with electret members 221, 222 made of macropolymer film such as PP, TFE, FEP on back electrodes 211, 212 made of a conductive metallic base on a grounded metallic plate or foil 20 are floated from ground and laminated by opposing back electrodes 211 and 212. On the electret member 222, a dielectric substance 24 made of a conductive metallic material or organic substance having equal or less area shape is laminated. Although the nonelectret part is present on the electret members 221, 222, charges corresponding to the algebraic sum of the potentials of both the electret elements are distributed uniformly on the entire surface of the dielectric substance 24. Thus, products rich in the moisture-proof and stable in the characteristics can be manufactured. |
