| 摘要 |
<p>16 An electro-acoustic transducer has a diaphragm which comprises a layer of a polymethacrylimide foam having a modulus of elasticity between 15.106 and 120.106 N/m2 and a density between 10 and 80 kg/m3. If the diaphragm is of a sandwich construction, the core layer is made of this polymethacrylimide foam and the skin layers are made of glass fibres, carbon fibres, cellulose fibres or polyaramide fibres. This results in a transducer having a higher efficiency and a lower distortion.</p> |
