| 摘要 |
<p>Disclosed is: an electret wherein vanishing of electric charges can be alleviated more than with conventional ones, even though the electret is easy to manufacture with a more simple construction; and a method of charging the electret, wherein the electret can be easily charged. An electrostatic-induction type conversion element (100) is provided with: an electret (10) comprising a substrate (11) that is comprised of an insulation material, a plurality of grid connection electrodes (12), a plurality of base electrodes (13), and an insulation material layer (14); a movable section (20) that is arranged facing the electret (10); and a resistor (30) connected to the electret (10) and the movable section (20). All the base electrodes (13) of the electret (10), the ground, and a needle electrode (41) are connected together, and further, a grid (40) and the grid connection electrodes (12) of the electret (10) are also connected together. Then, a prescribed voltage is applied between the needle electrode (41) and the base electrodes (13), charging the insulation material layer (14).</p> |
