| 摘要 |
<p>A loudspeaker comprising a corn-shaped diaphragm made of a material produced by ultrafine-foaming polyethylene terephthalate resin (PET) or polyethylene naphthalate resin (PEN) to an extent that the average cell size is 30 micrometers or less. The diaphragm is lightweight, highly rigid, and excellent in UV resistance. Therefore the quality of sound produced by the loudspeaker is improved. An LED of a support provided at a central magnetic pole is made to emit light on a voltage generated in an induction wiring by vibration of the diaphragm, thereby producing a visual effect.</p> |
