| 摘要 |
<p>A coil includes a first portion (415), a second portion (420), a third portion (427), and a fourth portion (428). The first portion (415) is wound in a first direction around a first core (435) and the second portion (420) is wound in the first direction around a second core (440). The third portion (427) is wound in a second direction that is different from the first direction around a third core (445) such that the third portion (427) is decoupled from the first and second portions (415, 420). Additionally, the fourth portion (428) is wound in the second direction aroung a fourth core (450) and decoupled from the first and second portions (415, 420). An inner area is formed by arranging the portions and a voltage is induced in the coil if an electrical conductor is placed in the inner area.</p> |
