| 摘要 |
PURPOSE:To eliminate the reflecting spuriousness by securing the prescribed combination of the widths between the electrode fingers of the both comb-line shape electrode and the prescribed distance between the electrode fingers. CONSTITUTION:Comb-teeth shaped electrode 22 is formed with electrode finger 23 possessing the lambda/8 width and electrode finger 24 possessing the 3lambda/8 width in combination, and the distance between the electrode fingers is set to lambda/8. Here lambda is the wavelength of the elastic surface wave. As a result, the phase of the compound vector of the reflecting components caused by the mismatching of the acoustic impedance of each electrode finger becomes reverse perfectly to the phase of the electrical reflecting component RE. Accordingly, the compound vector can be made zero. In such way, the reflecting spuriousness can be eliminated. |
