상세정보
학술지
High Performance Piezoelectric Microspeakers and Thin Speaker Array System
- 발행일
- 200912
- 출처
- ETRI Journal, v.31 no.6, pp.680-687
- ISSN
- 1225-6463
- 출판사
- 한국전자통신연구원 (ETRI)
- 협약과제
- 09MB1500, 유비쿼터스 단말용 부품 모듈, 김종대
- 초록
- This paper reports on an improved piezoelectric microspeaker with a high sound pressure level of 90 dB, a total harmonic distortion of less than 15%, and coherence higher than 0.9. The fabricated Pb(Zr,Ti)O3 (PZT) microspeakers have a thickness of only 1 mm including the speaker frame and an active area of 18 mm×20 mm. To achieve higher sound pressure and lower distortion, the PZT piezoelectric microspeaker has a well-designed speaker frame and a piezoelectric diaphragm consisting of a tilted PZT membrane and silicone buffer layer. From the simulation and measurement results, we confirmed that the silicon buffer layer can lower the first resonant frequency, which enhances the microspeaker's sound pressure at a low frequency range and can also reduce useless distortion generated by the harmonics. The fabricated PZT piezoelectric microspeakers are implemented on a multichannel speaker array system for personal acoustical space generation. The output sound pressure at a 30 cm distance away from the center of the speaker line array is 15 dB higher than the sound pressure at the neighboring region 30 degrees from the vertical axis. Copyright © 2009 ETRI.
- KSP 제안 키워드
- Active area, Buffer layer, High performance, Line array, Piezoelectric diaphragm, Resonant frequency(Fr), Simulation and measurement, Sound pressure level, Total Harmonic distortion, harmonic distortion(HD), low frequency range