| 摘要 |
PURPOSE:To attenuate an unnecessary signal by applying a resin or the like to both ends of a converting element at a part in contact with or nearly contacted to a piezoelectric porcelain electromechanical converting element of a glass delay medium. CONSTITUTION:The piezoelectric porcelain electromechanical converting elements 16 and 17 are fitted to an input/output part of the glass delay medium 15. An adhesives 18 made of epoxy resin or glassy material is applied to both end parts of the piezoelectric porcelains at a part in just contact with the piezoelectric porcelain or nearly contacted. A signal through paths other than the primary path is attenuated by applying the adhesives 18 and only the main signal is passed. Then, unnecessary reflected signals 20, 21 are very less in comparison with the main signal 19. Thus, the adhesive attenuates and decreases the unnecessary reflected level. |
