| 摘要 |
A surface acoustic electric wave device of the type comprising, over a large face of a planar piezo-electric substrate, a first row of parallel conductive fingers having an individual geometry chosen and distributed according to a chosen distribution arrangement along this row, a second row of parallel conductive fingers having an individual geometry chosen and distributed according to a chosen distribution arrangement along this row, the second row being interspaced from the first so as to allow a propagation of surface acoustic waves between the fingers of the first row and those of the second, which imparts to the device spectral and/or temporal characteristics defined by the acoustic propagation and the frequency selectivity due to the geometry of the fingers. The geometries of the fingers are chosen, in correspondence as from one row to the other, in order to obtain an acoustic coupling with a wide frequency bandwidth, and one of the two distribution arrangements or sequences for the attachment of the fingers is modified substantially periodically.
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