| 摘要 |
PROBLEM TO BE SOLVED: To provide an ultrasonic sensor capable of improving a short-range performance by simply and reliably accelerating the convergence of reverberation (voltage).SOLUTION: The ultrasonic sensor is adapted so that, after applying a reverse phase pulse signal 12 to a vibrator from a transmission drive part, an analog reverse phase signal 13 is applied to a vibrator, which is a signal having a reverse phase relative to a transmission drive pulse signal 11, the voltage value of which changes in proportion to a value of the reverberation voltage output from a reverberation voltage monitor. With this, the reverberation can be controlled corresponding to a waveform of the actually measured reverberation (voltage) output from the reverberation voltage monitor. Therefore, the reverberation (voltage) can be easily and reliably accelerated to converge irrespective of the changes in individual variation of the vibrator and temperature conditions. |
