| 摘要 |
PURPOSE:To increase S/N ratio of an ultrasonic signal and to obtain the information of a wide range, by increasing the energy of ultrasonic waves radiated from an ultrasonic wave oscillator. CONSTITUTION:A rectifying diode 12 is connected between a charging resistor 2 and a charge/discharge capacitor 6, and a switching means 15 which is ON/OFF with a signal fed to a charge switching trigger input terminal 14 is connected between the connecting point 13 with the diode 12 and the charging resistor 2 and ground terminal. With such a constitution, the switching means 15 is ON at the conduction of a thyristor 4 to interrupt the current from a charging resistor 2 and momentarily discharge the charge in a capacitor 6, allowing to minimize the charging resistor 2 and to select greater capacity of the charge/discharge capacitor 6 accordingly. Thus, the pulse peak value of the ultrasonic oscillator 10 is increased and also the ultrasonic wave energy is increased, allowing to increase the S/N ratio to secure the information of a wide variety. |
