| 摘要 |
PROBLEM TO BE SOLVED: To provide a piezoelectric sounding body and an electronic apparatus in which deterioration in acoustic characteristics incident to thinning can be suppressed. SOLUTION: A plurality of sound discharge holes 12 are formed in the case 10 of a portable telephone. Inside of a part provided with the sound discharge holes 12 serves as an air chamber 14 where a receiving section 16 for fixing a piezoelectric sounding element 20 is formed. The piezoelectric sounding element 20 has a bimorph structure where piezoelectric elements 24 and 26 are stuck to the both sides of a vibration cone 22, and the periphery of the vibration cone 22 is secured airtightly to the receiving section 16 so that it acts as a speaker. Acoustic characteristics of such a piezoelectric sounding body have a relation with the air passage, i.e. the total sum S of the side area of the sound discharge holes 12. When the total sum S is set in the range of 1.5-60 mm<SP>2</SP>, variation in resonance frequency and lowering of sound pressure are prevented and thereby required acoustic characteristics can be ensured while realizing reduction in thickness. COPYRIGHT: (C)2006,JPO&NCIPI
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