| 摘要 |
PURPOSE:To reduce the needless reflection in an electrode to improve frequency and time characteristics by setting the electrode width of a single-structure electrode non-crossing part so that the wave surface of a double finger-structure electrode part may be prevented from being shifted and arranging adjacent non-crossing parts in no parallel to each other. CONSTITUTION:In the elastic surface wave device provided with a combshaped electrode having an irregular crossing width, weighting electrode 41 and reguler-form electrode 41 are formed in the surface of piezoelectric substrate 40 by the photo lithography techneque, and a double finger structure to change the crossing width and the electrode width is given to the crossing part of weighting electrode 41 so that the impulse, which can be subjected to Fourier conversion on a basis of a prescribed frequency characteristic, may be generated. The electrode width of a single- structure electrode non-crossing part is so set that the wave surface of the surface wave, which is propagated through the double finger-structure electrode crossing part, and the wave surface of the surface wave, which is propagated through the electrode non-crossing part, may be prevented from being shifted, and adjacent electrode non-crossing parts are arranged in no parallel to each other. |
