| 摘要 |
PURPOSE:To efficiently diffuse the directional characteristic of a speaker by orienting the one face of a porous metal sintered plate to a circumference part according to a pressing and punching processing and using a tapered acoustic lends device. CONSTITUTION:The acoustic lens device 7 formed by the pressing and punching work applied to the porous metal sintered plate is mounted on the opening side of a speaker 8. The device 7 has an inclined form in a front face from a central part to a peripheral part. An opening part disposed on the diaphragm of the speaker or at the central part of the porous metal sintered plate mounted on the opening side of the speaker is a secondary sound source to increase an acoustic resistance to the circumference part. Thereby, the wave face of an equal phase has a circular arc form to increase the directional characteristic and diffuse it. |
