| 摘要 |
<p>PURPOSE:To measure the distance with high accudacy by receiving the signals transmitted from >=3 time-division intermittently driven oscillation sources, and calculating the distance via a zero-cross detector circuit, a counter circuit, a latch circuit, etc. CONSTITUTION:The ultrasonic sound generator of three oscillation sources, for example, are intermittently driven via an intermittently driven oscillator 12, a divide 13, etc. Thus the ultrasonic waves are transmitted. The reception signal of the reflected ultrasonic wave received from a measured object for the transmission signal of the ultrasonic wave is received by a receiver 14. At the same time, a zero-cross point of the received signal is detected by a zero-cross detector 15, and the time signal of the time counting result is stored in a latch circuit 17 from a signal shaping circuit 17 the delivery time of the ultrasonic wave. Then a distance is calculated from the transmitting/receiving times of the ultrasonic wave. In such a constitution where a zero-cross detector circuit is used, the distance can be measured with high accuracy in a wide virtual space without regulated by the direction-sensitivity dependency of the yltrasonic sound receiver.</p> |
