| 摘要 |
PURPOSE:To make it possible to obtain a high resolution image without aberration by dividing the curved part of an acoustic lens into a central region and a peripheral region, and constituting an ultrasonic wave processing surfaces corresponding to longitudinal waves or lateral waves which are separated in a body to be checked. CONSTITUTION:A coupler medium 5 is held between the flat surface of a specimen 8 and a non-spherical acoustic lens 10. The surface of the lens 10 is divided into two parts, i.e. a part L matching longitudinal waves and a part S matching lateral waves with a point gamma as a boundary. When the parallel sound waves from a transducer ware inputted into the surface of the specimen, longitudinal waves occupy the most part of the lens surface L at the central part. The waves are converged at a specified focal point 9 of the lens. The most of the longitudinal waves which are reflected and scattered are refracted and returned to the transducer as parallel sound flux. The sound flux passing the lens surface S at the peripheral part is converged at the focal point 9 of the lens by the same way as the lateral waves when the sound flux is refracted through the surface of the specimen 8. In this constitution, the converging property of the sound wave is improved, and a signal having high resolution can be obtained. |
