| 摘要 |
<p>PURPOSE:To expand a communications range between a read/write head and a data carrier. CONSTITUTION:A coil unit 2 is composed by providing both reception coils LR in cores Ca, Cb, and Cc and transmission coils LT on the outer periphery of the coils in front of the read/write head. A large number of such coil units 2A, 2B, 2C,... are adjacently mounted on the front surface of a case. The diameter of the transmission coil LT is made equal to the core diameter of the data carrier provided with a core. By employing such constitution, it is possible to expand a data communications area to a wide range along a surface confronting with the data carrier and the read/write head.</p> |
