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Multimedia English Teaching PP. Title: Application of Piezoelectric Ceramics in Communication system. Dr. & Prof. Chun-Huy Wang Electronical Engineering , Nan-Jeon Institute of Technology. Dielectric. Piezoelectric. Pyroelectric. Ferroelectric. < Electronic Ceramics >.
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Multimedia English Teaching PP. Title: Application of Piezoelectric Ceramics in Communication system Dr. & Prof. Chun-Huy Wang Electronical Engineering , Nan-Jeon Institute of Technology
Dielectric Piezoelectric Pyroelectric Ferroelectric <Electronic Ceramics > Dielectric Property Piezoelectricity Pyroelectricity Ferroelectricity
Piezoelectricity Mechanical and electrical energy conversion phenomena, discovered by France Scientist Pierre and Jacques Curie brother in 1880. Direct Piezoelectric Effect Mechanical Electrical Converse Piezoelectric Effect
Piezoelectric Ceramics cornal • (perovskite)結構,化學式為 center face center Pervoskite structure, with the chemical formula as ABO3 e.g. : BaTiO3
Piezoelectric Ceramics cornal center face center
Domain and domain boundaries of polycrystalline BaTiO3 -(Jaffe et al. 1971), (left)domain structure of unpoled ferroelectric ceramics – (right) graphical representation
Poling Poling is the final process in the fabrication. Initially, unpoled ceramics have no piezoelectricity because the piezoelectric tensors of the grains are randomly oriented. During the poling process, ferroelectric switching occurs and creates non zero overall piezoelectric tensors.
(1) unpoled (2) during poling (3) after poling
P~E Curve Domain Wall Movement
Communication Applications Piezoelectric ceramics used as the resonator and filter in communication system with frequency lower than 100MHz。 For frequency higher than 100MHz,the Surface Acoustic Wave (SAW) devices is used.
Communication Applications The ceramic filter and resonator are made of high stability piezoelectric ceramics that functions as a mechanical resonator. The frequency is primary adjusted by the size and thickness of the ceramic element. Typical application includes TVs, VCRs, telephones, remote controls and radios.
Ceramics Resonator Resonator is the basic frequency control component, the piezoelectric filter is composed by the piezoelectric resonator .
Ceramic Filter Monolithic Filter (used for low frequency)
SAW Resonator and Filter SAW : Surface Acoustic Wave In natural world, SAW can create by earthquake. In engineering, SAW can create by piezoelectric effect.
SAW Resonator and Filter Advantages of SAW High Sensitivity High Accuracy Passive Wireless Digitalized Mass Production Many Application Possibilities
SAW Resonator and Filter One Port Resonator Two Port Resonator
SAW Resonator and Filter Applications of SAW Filter PCS & CDMA Applications of SAW Filter GSM
SAW Resonator and Filter Applications of SAW Resonator
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