| 摘要 |
PURPOSE:To make a receiver small-sized, light-weight, and water-proof by sticking a thin plate consisting of piezoelectric materials to the inside of a cubic body and radiating directly acoustic waves from the surface of the cubic body. CONSTITUTION:A thin plate 17 consisting of piezoelectric materials is stuck to the inside face of a flat part of a cubic body 11 of a communication terminal device which is used while held with a hand. The resonance frequency between the flat part of the cubic body 11 and a bimorph oscillating part consisting of the thin plate 17 is set within a use frequency band. As the result, characteristics similar to a conventional single body-type receiver are obtained, and the receiver is small-sized, light-weight, and water-proof. |
