| 摘要 |
PURPOSE:To obtain excellent filter characteristics, by the constitution that the interval orthogonal to the direction of surface elastic wave propagation is greater at the main response section of the weighted electrode and smaller at the follower response section, in the surface elastic wave device consisting, for one electrode at least, of the driving electrode and the auxiliary electrode. CONSTITUTION:The auxiliary electrode 6 consisting of double electrode is provided for the part opposing in orthogonal direction to the direction of surface elastic wave propagation, at the driving electrode 5 being double electrode and weighted electrode. Further, the electrode interval W1 between the driving electrode 5 and the auxiliary electrode 6 for the main lobe (main response) section 4a of the envelope 4 is taken greater than the electrode interval W2 of the follower lobe (follower response) section 4b. Thus, excellent filter characteritics can be obtained without causing the excitation of unnecessary surface elastic waves at the operating region. |
