| 摘要 |
PURPOSE:To observe an internal state of an object which is optically opaque, by utilizing an ultrasonic beam radiated into 2 directions. CONSTITUTION:On a plate-like piezoelectric body 1 contacting with a liquid 4, an inter-digital transmitting electrode 2 formed by a comb tooth-like electrode 2a and 2b, and a receiving electrode being similar to said electrode are provided, and an ultrasonic wave is radiated in 2 different directions according to driving AC frequency. The ultrasonic wave in 2 directions, which is refracted on the surface of an observed object 5 through this electrode 2, goes in and is focused in the inside is transmitted, and when the reflected ultrasonic wave is received by the electrode 3, a phase difference corresponding to interference of 2 groups of receiving ultrasonic waves is varied in accordance with a state of the inside of the object 5, and an internal state of an object which is optically opaque can be observed non-destructively. |
