| 摘要 |
PURPOSE:To obtain a sharp hologram of a curved specimen by detecting the phase difference between the phases of reflected waves and a reference wave, and correcting the same according to the distance between the curved surface of the specimen and a hologram surface. CONSTITUTION:This ultrasonic holography device has a curved surface scanning means scanning a focusing type transducer along the curved surface of a specimen, a deviation detecting means detecting the distance between the curved surface and a hologram surface cooperatively with the transducer, and a position correcting circuit correcting the phase of the reference wave or reflected waves according to the deviation thereof. By the phase equation (1) of the wave from the defect P at the point T and a reference wave phiR, phi1=phiP-phiR is recorded in a hologram. The distortion expressed by the equation (2) by curving is produced, but if the value of the equation (3) determined by the transducer position T is added to, for example, a reference wave RW, the phase on the hologram is the equation (4). |
