| 摘要 |
PROBLEM TO BE SOLVED: To provide a piezoelectric speaker used also as an antenna for making it possible to use at frequencies of MHz band while upsizing of its profile caused by common use as the antenna is restricted to a minimum. SOLUTION: The antenna 4 is provided at a frame 2a as a peripheral edge portion of a diaphragm 2. While using also as an antenna, upsizing of the profile can be restricted to a minimum, and space saving of the apparatus is made enabled when it is applied to small electronic devices, such as a cellular phone. In this case, the antenna 4 is a loop antenna formed in the shape of a loop, so it can be used at frequencies of MHz band, which is used in, for example, non-contact IC card technology. In addition, magnetic body sheet 5 is formed, opposite to the antenna 4, on the other face of the frame 2a, so a decrease in receive sensitivity can be suppressed low if there is metallic material near to the antenna 4. COPYRIGHT: (C)2009,JPO&INPIT
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