| 摘要 |
PURPOSE:To measure the surface form with a high resolution even in the case of a low measuring frequency by excluding the perpendicular incident component of an ultrasonic beam which scans a body to be examined. CONSTITUTION:A focus convergence type ultrasonic probe 2 is moved two- dimensionally by a scanner 3 to scan a body 1 to be examined on a plane and receives a transmission pulse from a pulsar receiver 5 of an ultrasonic flow detector 4 and irradiates the body 1 to be examined with an ultrasonic beam. The probe 2 converts the received reflection wave to an electric signal and sends it to the receiver 5, and the receiver 5 extracts a specific reception signal by gating and sends it to an image processing device 7 through an amplifying circuit 6. With respect to the probe 2, the center part of an acoustic concave lens 2a is masked to exclude the acoustic component made perpendicularly incident on the body 1 to be examined, and only oblique components of an acoustic wave 9 are radiated and are converged at a focus F before the body 1 to be examined. Thus, the reflected wave is not made incident on the lens 2a when the body 1 to be examined is flat, and the ruggedness appears as the height of the echo level, and the surface form is measured with a high resolution though a low measuring frequency is used. |
