| 摘要 |
PURPOSE:To attenuate unnecessary oscillations of an ultrasonic wave, by providing a resin having porous structure on a surface encircled with a normal ultrasonic propagation path perpendicular to the thickness direction of the delay line medium of an ultrasonic wave delay line. CONSTITUTION:Metallic fine particles of nickel, tungsten, etc., of uniform particle size and a blowing agent are incorporated in an epoxy resin for unnecessary oscillation attenuation and stirring or air blowing is so carried out that fine bubbles are formed uniformly in the resin. Then, the resin is applied over a part encircled with the normal ultrasonic wave propagation path in a plane perpendicular to the thickness direction of a glass medium 1 for the ultrasonic wave delay line and cured at specific temperature. Consequently, the fine bubbles 9 are left in the resin 8 and unnecessary oscillations of an ultrasonic wave are scattered and reflected by curved surfaces of the bubbles to enhance attenuation effect. |
