Sensor utilizing ultrasonic transducer and method for reducing ringing time thereof

Abstract

A sensor utilizing an ultrasonic transducer is disclosed. The sensor includes a sending circuit module and a receiving circuit module, the sending circuit module applies a first electric drive signal including a plurality of pulses to the ultrasonic transducer, and the receiving circuit module detects the reflected wave received by the ultrasonic transducer and generates a receiving electrical signal , wherein, after applying the first electric drive signal, the transmitting circuit module applies to the ultrasonic transducer a second electric drive signal comprising a plurality of anti-phase pulses having an anti-phase relationship with the first electric drive signal, and the multiple The anti-phase pulses are controlled to apply sequentially decreasing energy from pulse to pulse to the ultrasound transducer.

Description

technical field [0001] The present invention relates to a distance sensor using an ultrasonic transducer and a method for reducing the ringing time of the distance sensor, in particular to a circuit and a method for reducing the ringing time by controlling the driving pulse signal of the ultrasonic transducer. Background technique [0002] Sensors that use ultrasonic waves to measure distances sense signals received by reflections from objects after sending out ultrasonic waves. At this time, the time interval between the transmitted ultrasonic signal and the received ultrasonic signal is measured, and the distance from the point where the ultrasonic wave is transmitted to the object is measured by distance calculation considering the speed of sound wave transmission. [0003] At this time, in many cases, the device that transmits the ultrasonic wave vibrates the Piezoelectric Film (Piezoelectric Film) transducer, etc. through an electric drive signal of a specific frequency...

AI Technical Summary

Problems solved by technology

At this time, the signal of the reflected wave ES of the object is weak, but on the contrary, the after-oscillation ultrasonic signal RS has a larger amplitude than the reference amplitude L of the reflected wave ES in a relatively long time period Zd, so in the time period Zd, even if Received reflected wave ES can not measure the accurate distance

That is, although the driving time of applying the electric driving signal DS is t0, due to aftershock, the piezoelectric film needs to become stable before time t1 until the minimum distance can be measured

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