| 摘要 |
PURPOSE:To facilitate the production of an ultrasonic oscillator by combining microoscillator pieces each having a square plate shape to a mosaic shape along a spherical crown-shaped concave surface, thereby forming the ultrasonic oscillator. CONSTITUTION:The ultrasonic oscillator 1 is combined with the microoscillator pieces 2 each having the square plate shape to the mosaic shape along the spherical crown- shaped concave face (radius R of curvature) by which the oscillator is formed to a concave mirror shape as a whole. The ultrasonic waves emitted in the normal direction of the individual oscillator pieces 2 focus at the center of the spherical crown- shaped concave face and a visualized region is formed before and after the focus if the respective oscillator pieces 2 are simultaneously excited. The oscillator pieces 2 are obtd. by cutting flat plate piezo-electric ceramics having a uniform thickness to the mesh shape. After these pieces are tentatively attached to a jig having the spherical segment-shaped convex face (radius R of curvature) in the mosaic shape, a liquid rear face material such as epoxy resin is cast by using a molding flask, etc., and is solidified. The oscillator pieces are thus integrated and fixed by the rear face material 4. Since the oscillator 1 is formed in such a manner, the need for grinding to the concave face is not required and the production of the oscillator 1 is facilitated. |
