| 摘要 |
<p>PURPOSE:To simplify the structure of the device by providing on a base plate a magnetostrictive delay line with both ends fixed, providing a magnetostriction generating means and a detecting means in the vicinity of a reference point of the magnetostrictive delay line and thus constituting the device so as to detect a reflected wave at a detecting point. CONSTITUTION:On the base plate 11 is provided one magnetostrictive delay line 1 with both ends supported by a dampers 7 and 8, while on one end thereof are arranged fixedly a driving coil 2 and a detecting coil 3 which is separated in length l from the former. When the detecting point p separated in Lx from the detecting coil 3 is pressed by a finger, the position of the point p is found from a time required from application of a pulse to the driving coil 3 to detection of the reflected wave from the detecting point p. When a counter is employed, it is offset beforehand by a count value equivalent to the value of l and by a count value equivalent to a phase difference between a traveling wave and the reflected wave. By this constitution, the structure of the device is simplified.</p> |
