| 摘要 |
PURPOSE:To attenuate unnecessary reflection waves, by splitting electrodes having reflecting effect provided between input and output electrodes in parallel with propagation direction of surface waves and locating them with a shift. CONSTITUTION:A periodical construction 3 provided between an input electrode 2 and an output electrode 4 is split into two at the middle, and they are located toward propagation direction with a shift of 1/4 wavelength. Since the reflecting wave from the construction 3 to the input electrode 2 is shifted for the phase by pi at the split part, a part of reflection surface acoustic wave energy of the both is cancelled partly at the output electrode 4. As a result, multiplex reflection can be attenuated effectively and the characteristics of surface acoustic wave device having a narrow block band in the band can be improved. |
