| 摘要 |
PURPOSE:To measure the thickness of a body to be measured accurately through simple operation by using angle information which is obtained by a reflected wave from the body and the difference in reception time between waves from the top surface and bottom surface of the body for arithmetic. CONSTITUTION:An ultrasonic wave having a predetermined amplitude is projected 5 upon the body 3 to be measured and a reflected wave from the body 3 is received 6. The amplitude of the receive wave is discriminated 8 on the basis of a predetermined threshold value and the angle of the ultrasonic wave to the body 3 is measured by the discrimination output when the receive wave amplitude exceeds the threshold value to store 10 the angle measurement output as the angle information. Further, the difference in the receive wave time between when a reflected wave from the top surface 3a of the body 3 is received and when a reflected wave from the bottom surface 3b is received is measured 11, and the thickness of the body 3 is calculated 15 on the basis of this measurement output and the stored angle information. |
