| 摘要 |
PURPOSE:To prevent the occurrence of the flaking of an electrode in the measurement of high sound pressure by providing a second electrode layer consisting of gold on the front and the rear surfaces of a high molecular piezoelectric body through the first electrode layer of high adhesive power consisting of nickel or chromium, and further, covering the second electrode layer on the front and the rear surfaces of the high molecular piezoelectric body with the resin of good water resistance. CONSTITUTION:As for an electrode part 3, the first electrode layer 3a consisting of nickel or chromium is formed in about 500 angstrom thickness and about 1mm diameter on the front and the rear surfaces of a PVDF film 1 respectively, and the second electrode layer 36 consisting of gold is formed in the nearly same shape and the nearly same thickness as the first electrode layer 3a over it. Thus, the adhesive power of the electrode part 3 to the PVDF film 1 is improved remarkably, and mechanical strength endurable against the measurement of the high sound pressure for a long time is realized. Further, since in this hydrophone, the surfaces of the electrode part 3 and a reed electrode 4 are never immersed directly into water by the assistance of the resin 6, the possibility of the occurrence of a pit on the surface of the electrode part 3 due to the cavitation is removed. |
