摘要 |
<P>PROBLEM TO BE SOLVED: To attenuate a signal level only in a frequency bandwidth which is subject to the attenuation of the signal level and further increase the attenuation. <P>SOLUTION: Two piezoelectric substrates 5, 6 are hermetically sealed in a band rejection filter. A pair of input and output electrodes is formed on one surface of each piezoelectric substrate 5, 6 and a ground electrode corresponding to the pair of input and output electrodes is formed on the other main surface of each piezoelectric substrate 5, 6. An input oscillation electrode and an output oscillation electrode are disposed on the one main surface having a gap therebetween to form each pair of the input and output electrodes. Further, the input oscillation electrode and the output oscillation electrode of the piezoelectric substrate 5 are respectively and mutually connected with the input oscillation electrode and the output oscillation electrode of the piezoelectric substrate 6. <P>COPYRIGHT: (C)2012,JPO&INPIT |