| 摘要 |
<p>An ultrasonic measurement method in an ultrasonic measurement system having an ultrasonic transducer (6) includes emitting an ultrasonic pulse (26) from the ultrasonic transducer. An ultrasonic pulse is received in accordance with a pulse travel time wherein the amplitude of the received ultrasonic pulse varies according to the pulse travel time. A first electrical signal is provided representative of the received ultrasonic pulse wherein the amplitude of the first electrical signal varies in accordance with the pulse travel time. A second electrical signal is provided in accordance with the first electrical signal wherein the amplitude of the second electrical signal is substantially independent of the pulse travel time. In order to determine the second electrical signal variable amplification is applied to the first electrical signal in accordance with the travel time. A distance is determined according to the pulse travel time wherein the distance is representative of the distance between the transducer and a material surface (18).</p> |
