| 摘要 |
PURPOSE:To attain wide-range used by increasing greatly the degree of freedom as to the setting of the peak frequency position of a comb line characteristic filter by a elastic surface wave. CONSTITUTION:Output electrodes 18 and 19 constituting the 1st electrode group are connected in parallel at distance X on the same propagation line and equal in opening length W. On the propagation line adjoining to that of electrodes 19 and 20, electrodes 20 and 21 forming the 2nd electrode group are similarly connected in parallel at distance X and share bas bar part 24 with electrodes 18 and 19. Their opening length W2 differs from W1 so that W1:W2=3<1/2>:1 and while electrodes 20 and 21 are closer to the output side than electrodes 18 and 19 by lambda0/4 where the electrode wavelength is lambda0, electrode 21 has the opposite polarity to three other electrodes. Thus, when the peak frequency position of comb line characteristics of a elastic surface wave is set, the great degree of freedom can be obtained and wide range use can be realized. |
