| 摘要 |
PURPOSE:To reduce a loss by forming distribution constant lines of metal strips by making parallel connections with input electrodes while obtaining the capacity more than a prescribed value by varying the number of electrode fingers or opening length. CONSTITUTION:On piezoelectric substrate 1, output electrode 3 having several electrode fingers varying in electrode finger pitch in the order of P1-Pn-1 is formed and while input electrode 2 and output electrode 3 are connected at one-side terminals to input terminal 4 applied with an electric signal or output terminal 5 from which an output electric signal is extracted, the other-side terminals are grounded. The capacitance of either one of input and output electrodes is in proportion to the product of opening length W and the number (n) or (m) of electrode fingers. For this purpose, the capacity is set to >=7 pF by varying the number (n) and (m) of electrode fingers or opening length W and parallel connections with input electrodes 2 and 3 are made so as to distribution constant lines 6 and 7 of metallic strips. Thus, a loss can be reduced by about 10 dB. |
