| 摘要 |
<p>A cylindrical transducer is defined by a pair of concentric members formed from a suitable material such as quartz and fused at their ends and separated from each other by a relatively small distance along an intermediate portion of their axial lengths. Thin layers of an electrically conductive material are provided on the adjacent surfaces of the concentric members along the intermediate portions of their axial lengths. The outer member is provided with a progressively increasing thickness near the axial ends of the member. The thickness of the outer member increases with progressive positions towards the axial ends to prevent the member from cracking when subjected to stresses. The thin conductive layers on the members are formed by plating a thin layer of a noble metal such as platinum on the annular surfaces of the quartz members and then applying heat to the quartz members at a particular temperature such as approximately 1050.degree.C. for a particular period of time such as approximately fifteen (15) minutes. This process is repeated several times with successive thin layers of the noble metal to provide a fusion of the platinum to the quartz and to provide a progressive change from platinum silicide at the surface of the quartz to platinum at the exposed surface of the conductive layer.</p> |
