| 摘要 |
A langasite crystal substrate having a prescribed range of Euler angles for substrate and crystal orientation improves signal processing for a surface acoustic wave (SAW) device, and thus for radiotelephones, mobile communication systems, television systems, and the like. When a voltage is applied to an input interdigital transducer IDT (2), a surface acoustic wave is generated in a piezoelectric substrate of langasite (1). This wave propagates in a direction generally perpendicular to electrodes of the IDT (2). The langasite crystal cut and wave propagation directions are defined which reduce insertion loss due to SAW transduction, diffraction, and beam steering. Temperature stability is improved. A low power flow angle and reduced level of diffraction is also achieved. <IMAGE> |
